Cannabis Cognition Research

Mapping the acute effects of cannabis on multiple memory domains: A randomized, double-blind, placebo-controlled study.

Cuttler, Carrie · 2026

Compared to placebo, cannabis increased false memory susceptibility and impaired verbal memory (immediate, delayed, working), visuospatial memory (immediate, delayed), event-cued prospective memory, source memory, and temporal order memory.

Cannabis use, cognitive function and dementia risk in older adults: observational and genetic analyses.

Ishrat, Saba · 2026

In the UK Biobank, cannabis users performed modestly better on some baseline cognitive tests but showed no difference in longitudinal cognitive change.

Youth cannabis and alcohol use expectancies mediate associations between pre-adolescent cognitive function and subsequent use initiation.

Jones, Stephanie K · 2026

Higher general ability at ages 9-10 was associated with cannabis initiation by 13-14 (OR=1.23), with positive cannabis expectancies mediating 72.6% of the effect (p=0.003).

A Randomized Controlled Trial of the Safety and Efficacy of Dronabinol for Agitation in Alzheimer's Disease.

Rosenberg, Paul B · 2026

In a 3-week RCT of 75 Alzheimer's patients, dronabinol decreased agitation significantly more than placebo on the Pittsburgh Agitation Scale (effect size 0.53, p=0.015).

Cannabis Use Among US Adolescents.

Sultan, Ryan S · 2026

Compared to non-users, even noncurrent and monthly cannabis users had greater odds of poor academic performance (aOR 1.30-2.20), poor impulsivity and self-regulation (aOR 1.26-2.19), and adverse emotional states (aOR 1.1-1.42).

Independent brain cortical signatures of risk for adolescent cannabis use and consequences of such use are moderated by sex.

Watts, Jeremy J · 2026

In years when adolescents used more cannabis than their personal average, cortical thickness was lower (p = 0.047).

Randomized Laboratory Study of Single-Dose Cannabis, Dronabinol, and Placebo in Patients With Schizophrenia and Cannabis Use Disorder.

Brunette, Mary F · 2025

Oral dronabinol (15 mg) worsened verbal learning (B = -9.89) and attention (B = -0.61) in the schizophrenia-CUD group compared to placebo.

Brain Function Outcomes of Recent and Lifetime Cannabis Use.

Gowin, Joshua L · 2025

Using Human Connectome Project data, heavy lifetime cannabis users (>1,000 uses, n=88) showed significantly lower brain activation during a working memory task compared to nonusers, with a moderate effect size (Cohen d = -0.28).

Lifetime Cannabis Use Is Associated with Brain Volume and Cognitive Function in Middle-Aged and Older Adults.

Guha, Anika · 2025

Using UK Biobank data from participants aged 40-70 (mean age 54.5), lifetime cannabis use was positively associated with regional brain volume in CB1-rich areas including the caudate, putamen, hippocampus, and amygdala.

The Individual and Interactive Effects of Alpha-Pinene and Delta-9-Tetrahydrocannabinol in Healthy Adults.

Kumar, Lakshmi · 2025

Alpha-pinene alone (15mg) had no effects vs.

Association of childhood mental health and cognition with longitudinal patterns of cannabis problems in adolescence.

Lees Thorne, Rachel · 2025

Five trajectories identified: stable-no problems (85%), early-onset high (2%), late-onset high (3%), early-onset low (6%), late-onset low (5%).

DNA methylation profiles of long-term cannabis users in midlife: a comprehensive evaluation of published cannabis-associated methylation markers in a representative cohort.

Meier, Madeline H · 2025

Analysis of the Dunedin Multidisciplinary Health and Development Study revealed that decades of cannabis use was associated with specific DNA methylation changes, a type of epigenetic modification that can alter gene expression without changing the DNA sequence itself..

Cognitive Difficulty Concentrating, Remembering, or Making Decisions According to Chronic Medical Conditions and Cannabis Use Among US Adults in 2022.

Merrill, Ray M · 2025

Among 94,918 U.S.

Risk of Dementia in Individuals With Emergency Department Visits or Hospitalizations Due to Cannabis.

Myran, Daniel T · 2025

Individuals aged 45+ with acute care due to cannabis use had a 5.0% rate of dementia diagnosis within 5 years, compared to 3.6% for all-cause acute care and 1.3% in the general population.

The psychosis continuum: Systematic review on prodromal markers, symptom progression, and early intervention strategies.

Ricci, Valerio · 2025

This systematic review synthesized 60 studies spanning 25 years (2000–2025) to map the trajectory from early warning signs to full psychotic episodes.

Neurocognitive outcomes in adolescents with and without four weeks of cannabis abstinence: a randomized clinical trial using contingency management.

Schuster, Randi M · 2025

At baseline, cannabis-using adolescents had worse verbal memory and processing speed than non-users.

Cannabis use disorder contributes to cognitive dysfunction in Veterans with traumatic brain injury.

Esmaeili, Aryan · 2024

Cognitive disorder incidence was highest in Veterans with both TBI and CUD (1.83 per 10,000 person-months), followed by TBI only (1.03), CUD only (0.68), and controls.

The prevalence of cannabis use disorder in attention-deficit hyperactivity disorder: A clinical epidemiological meta-analysis.

Froude, Anna M · 2024

Lifetime CUD prevalence in ADHD populations was 26.9%, with current prevalence at 19.2%.

Cannabidiol does not attenuate acute delta-9-tetrahydrocannabinol-induced attentional bias in healthy volunteers: A randomised, double-blind, cross-over study.

Oliver, Dominic · 2024

THC (10 mg) increased attentional bias (d=0.41, P=0.03).

Birth, cognitive and behavioral effects of intrauterine cannabis exposure in infants and children: A systematic review and meta-analysis.

Sorkhou, Maryam · 2024

Intrauterine cannabis exposure was associated with preterm delivery (OR=1.68, p=0.03), low birth weight (OR=2.60, p<0.001), and NICU admission (OR=2.51, p<0.001).

Evaluating possible 'next day' impairment in insomnia patients administered an oral medicinal cannabis product by night: a pilot randomized controlled trial.

Suraev, Anastasia · 2024

At 9+ hours after evening administration of 10mg THC/200mg CBD oil, there were no differences from placebo on 27 of 28 cognitive and psychomotor tests, including simulated driving performance.

Prenatal cannabis use and the risk of attention deficit hyperactivity disorder and autism spectrum disorder in offspring: A systematic review and meta-analysis.

Tadesse, Abay Woday · 2024

Prenatal cannabis exposure was associated with increased ADHD symptoms (B=0.39, p=0.001) and a 30% higher risk of ASD (RR=1.30, p<0.05).

A robust brain network for sustained attention from adolescence to adulthood that predicts later substance use.

Weng, Yihe · 2024

Brain connectivity patterns associated with poor sustained attention at age 14 predicted subsequent increases in cannabis and cigarette use through age 23.

Differential associations of adolescent versus young adult cannabis initiation with longitudinal brain change and behavior.

Albaugh, Matthew D · 2023

Adolescent cannabis initiation (14-19) was associated with cortical thinning in dorsolateral and ventrolateral prefrontal cortex that persisted into young adulthood and partially mediated associations with later cocaine, ecstasy, and cannabis use at age 22.

Cannabis in Adolescence: Lasting Cognitive Alterations and Underlying Mechanisms.

Scheyer, Andrew F · 2023

Cannabis use during adolescence causes lasting aberrations in synaptic development, often secondary to epigenetic changes.

Task-independent acute effects of delta-9-tetrahydrocannabinol on human brain function and its relationship with cannabinoid receptor gene expression: A neuroimaging meta-regression analysis.

Gunasekera, Brandon · 2022

THC had neuromodulatory effects across a core network of brain regions central to many cognitive tasks and processes.

A Meta-Analysis of fMRI Studies of Youth Cannabis Use: Alterations in Executive Control, Social Cognition/Emotion Processing, and Reward Processing in Cannabis Using Youth.

Hammond, Christopher J · 2022

Cannabis-using youth showed greater activation in the rostral medial prefrontal cortex during executive control tasks and decreased activation in the dorsal medial prefrontal cortex and dorsal anterior cingulate during social cognition and emotion processing, compared to non-using peers..

Attention deficit hyperactivity disorder symptoms and cannabis use after one year among students of the i-Share cohort.

Jean, François Arnaud Matthieu · 2022

Higher ASRS scores were associated with greater probability of cannabis use after one year (OR 1.24 for occasional use, OR 1.43 for frequent use).

The CannTeen study: verbal episodic memory, spatial working memory, and response inhibition in adolescent and adult cannabis users and age-matched controls.

Lawn, W · 2022

Cannabis users had significantly worse verbal episodic memory than controls (p=0.007).

Systematic review of structural and functional neuroimaging studies of cannabis use in adolescence and emerging adulthood: evidence from 90 studies and 9441 participants.

Lichenstein, Sarah D · 2022

Across 90 studies including 9,441 participants (3,924 cannabis users, 5,517 non-users), preliminary evidence pointed to alterations in frontoparietal, frontolimbic, frontostriatal, and cerebellar regions among adolescent and emerging adult cannabis users..

Alcohol and cannabis co-use and longitudinal gray matter volumetric changes in early and late adolescence.

Luo, Xi · 2022

Co-use of alcohol and cannabis predicted faster gray matter volume decline (-0.046 to -0.138 cm3/year) in the caudal middle frontal cortex, fusiform, inferior frontal, superior temporal, and supramarginal gyri.

Driving Performance and Cannabis Users' Perception of Safety: A Randomized Clinical Trial.

Marcotte, Thomas D · 2022

THC significantly impaired the Composite Drive Score at 30 minutes (d=0.59) and 1.5 hours (d=0.55), with borderline impairment at 3.5 hours (d=0.29) and no difference at 4.5 hours.

Long-Term Cannabis Use and Cognitive Reserves and Hippocampal Volume in Midlife.

Meier, Madeline H · 2022

Long-term cannabis users showed a mean 5.5-point IQ decline from childhood to age 45, poorer learning and processing speed relative to childhood IQ, and informant-reported memory and attention problems.

Longitudinal effects of cannabis use on attentional processes in patients with first episode of psychosis.

Setién-Suero, Esther · 2022

Over 3 years, attention improved most in FEP patients who never used cannabis (n=238), followed by ex-users (n=105) and persistent users (n=43).

The effects of cannabis and alcohol on driving performance and driver behaviour: a systematic review and meta-analysis.

Simmons, Sarah M · 2022

Cannabis alone impaired lateral control (lane weaving) and decreased driving speed.

Use of Marijuana: Effect on Brain Health: A Scientific Statement From the American Heart Association.

Testai, Fernando D · 2022

Cannabinoid receptors are concentrated in brain areas critical for cognition and behavior, especially during neurodevelopment.

Association of Cannabis Use During Adolescence With Neurodevelopment.

Albaugh, Matthew D · 2021

Cannabis use between ages 14 and 19 was associated with accelerated, dose-dependent cortical thinning in bilateral prefrontal cortex, spatially correlated with CB1 cannabinoid receptor density.

Neuropsychological and neurophysiological predictors and consequences of cannabis and illicit substance use during neurodevelopment: a systematic review of longitudinal studies.

Debenham, Jennifer · 2021

High-quality evidence showed that delayed or irregular neurodevelopment in executive functioning, particularly emotional perception, may predispose young people to higher frequency substance use.

The Effects of Alcohol and Cannabis Use on the Cortical Thickness of Cognitive Control and Salience Brain Networks in Emerging Adulthood: A Co-twin Control Study.

Harper, Jeremy · 2021

Greater alcohol misuse was linked to thinner cortex in prefrontal, temporal, insula, and parietal regions, predominantly right-lateralized.

Alcohol and Cannabis Use and the Developing Brain.

Lees, Briana · 2021

Heavy alcohol use was associated with widespread decreases in gray matter volume and slowed white matter growth, while heavy cannabis use was linked to decreased subcortical volume and increased cortical thickness.

Determining the magnitude and duration of acute Δ9-tetrahydrocannabinol (Δ9-THC)-induced driving and cognitive impairment: A systematic and meta-analytic review.

McCartney, Danielle · 2021

At peak effect, THC significantly impaired lateral control, tracking, and divided attention.

Associations Between Prenatal Cannabis Exposure and Childhood Outcomes: Results From the ABCD Study.

Paul, Sarah E · 2021

Children exposed to cannabis prenatally showed greater psychotic-like experiences, internalizing, externalizing, attention, thought, and social problems, more sleep difficulties, higher BMI, and lower cognitive performance.

The Behavioral Sequelae of Cannabis Use in Healthy People: A Systematic Review.

Sorkhou, Maryam · 2021

Across 124 studies of cannabis effects in people without psychiatric or medical conditions, frequency of use, THC content, age of onset, and cumulative exposure all contributed to adverse behavioral outcomes including impaired cognition, motivation, mood, anxiety, psychosis risk, and psychosocial functioning..

Premorbid Adjustment and IQ in Patients With First-Episode Psychosis: A Multisite Case-Control Study of Their Relationship With Cannabis Use.

Ferraro, Laura · 2020

Psychosis patients who used cannabis occasionally or daily had better premorbid social adjustment than patients who never used.

Reduced Segregation Between Cognitive and Emotional Processes in Cannabis Dependence.

Manza, Peter · 2020

Using Human Connectome Project data from 89 cannabis-dependent individuals, 87 recreational users, and matched controls, researchers found that cognitive and emotional measures were significantly correlated in the cannabis-dependent group only.

Impact of cannabis and low alcohol concentration on divided attention tasks during driving.

Miller, Ryan E · 2020

In a randomized, placebo-controlled crossover driving simulator study, each 1 ug/L increase in blood THC predicted increased odds of failing to complete a console search task (OR 1.05), more incorrect responses (OR 1.05), speed declines during mirror tasks, and longer lane departures.

Do cannabis use disorders increase medication non-compliance in schizophrenia?: United States Nationwide inpatient cross-sectional study.

Patel, Rikinkumar S · 2020

Among 1,030,949 schizophrenia inpatients (2010-2014), 26% were non-compliant with medications.

Cannabis use, cognitive performance, and symptoms of attention deficit/hyperactivity disorder in community adults.

Petker, Tashia · 2020

After controlling for age, income, sex, alcohol, and tobacco use, cannabis use severity predicted greater hyperactive-impulsive and inattentive ADHD symptom endorsement in 1,008 adults, but was not associated with other neurocognitive measures.

Pharmacodynamic dose effects of oral cannabis ingestion in healthy adults who infrequently use cannabis.

Schlienz, Nicolas J · 2020

In a placebo-controlled study with 17 infrequent cannabis users, 10 mg THC produced discriminable subjective effects and elevated heart rate but did not impair cognition.

Greater delay discounting and cannabis coping motives are associated with more frequent cannabis use in a large sample of adult cannabis users.

Sofis, Michael J · 2020

Latent class analysis identified three use groups: low (23%, 1-9 days/month), moderate (41%, 10-29 days/month, 2-3 times/day), and high (36%, daily, 4+ times/day).

Attention-deficit/hyperactivity disorder and lifetime cannabis use: genetic overlap and causality.

Soler Artigas, María · 2020

Using GWAS data from 53,293 ADHD and 32,330 cannabis use subjects, genetic correlation between ADHD and lifetime cannabis use was r2=0.29 (p=1.63×10-5).

Dark Classics in Chemical Neuroscience: Δ9-Tetrahydrocannabinol.

Banister, Samuel D · 2019

THC primarily acts as a partial agonist at CB1 receptors, producing its distinctive intoxication.

The neuropsychopharmacology of cannabis: A review of human imaging studies.

Bloomfield, Michael A P · 2019

Cannabis and THC acutely affect executive, emotional, reward, and memory processing through direct CB1 effects and indirect effects on glutamate, GABA, and dopamine systems.

Alteration to hippocampal volume and shape confined to cannabis dependence: a multi-site study.

Chye, Yann · 2019

Cannabis users as a whole (n=140) did not differ from controls (n=121) in hippocampal volume or shape.

Genome-wide association study implicates CHRNA2 in cannabis use disorder.

Demontis, Ditte · 2019

A variant (rs56372821) near the CHRNA2 gene reached genome-wide significance for cannabis use disorder risk (P = 9.31 x 10^-12) and replicated independently (P = 3.27 x 10^-3).

Coming off cannabis: a cognitive and magnetic resonance imaging study in patients with multiple sclerosis.

Feinstein, Anthony · 2019

After 28 days of abstinence, the withdrawal group performed significantly better on every cognitive measure (P < 0.0001 for all) compared to the continuation group.

Exposure to cannabinoids can lead to persistent cognitive and psychiatric disorders.

Krebs, Marie-Odile · 2019

Cannabis use is associated with dose-dependent cognitive deficits and a 2-fold or greater increase in psychosis risk.

Does regular cannabis use affect neuroanatomy? An updated systematic review and meta-analysis of structural neuroimaging studies.

Lorenzetti, Valentina · 2019

Regular cannabis users had significantly smaller volumes of the hippocampus (SMD=0.14) and both medial (SMD=0.30) and lateral (SMD=0.19) orbitofrontal cortex compared to controls.

Associations between adolescent cannabis use frequency and adult brain structure: A prospective study of boys followed to adulthood.

Meier, Madeline H · 2019

Four adolescent cannabis use trajectories were identified: non-users/infrequent, desisters, escalators, and chronic-frequent users.

A Population-Based Analysis of the Relationship Between Substance Use and Adolescent Cognitive Development.

Morin, Jean-François G · 2019

Cannabis showed lagged (neurotoxic) effects on inhibitory control and working memory, and concurrent effects on delayed memory recall and perceptual reasoning.

Residual effects of cannabis use in adolescent and adult brains - A meta-analysis of fMRI studies.

Blest-Hopley, Grace · 2018

Researchers conducted separate meta-analyses of fMRI studies comparing brain function in adult and adolescent cannabis users to non-users during various cognitive tasks. In adult cannabis users (530 users vs 580 controls across 13 studies), brain activation was increased in the superior and posterior temporal regions and inferior frontal gyrus, while decreased in the visual cortex, insula, and middle temporal gyrus.

Meta-analysis of neurocognition in young psychosis patients with current cannabis use.

Bogaty, Sophia E R · 2018

Previous research had suggested that psychosis patients with lifetime cannabis use appeared to have better cognitive function than non-using patients.

Associations between childhood ADHD, gender, and adolescent alcohol and marijuana involvement: A causally informative design.

Elkins, Irene J · 2018

Researchers studied 3,762 twins (64% identical) to determine whether childhood ADHD causally leads to adolescent substance use or whether shared genetic and environmental factors explain the link. Children with more severe ADHD symptoms initiated alcohol and marijuana use earlier, escalated to frequent or heavy use faster, and developed more symptoms of substance use problems by age 17. Females with more hyperactivity-impulsivity had higher alcohol consumption and progressed further toward daily marijuana use than males with similar symptoms. The critical test: when identical twins who differed in ADHD severity were compared, the twin with more severe ADHD did not have significantly worse substance outcomes than their co-twin.

Individual and combined effects of acute delta-9-tetrahydrocannabinol and cannabidiol on psychotomimetic symptoms and memory function.

Morgan, Celia J A · 2018

Forty-eight cannabis users were selected based on schizotypal personality scores and use frequency, then received four vaporized conditions in crossover design: placebo, THC 8 mg, CBD 16 mg, and THC 8 mg + CBD 16 mg. THC alone increased psychotic symptoms on the PSI, increased negative symptoms on the BPRS, and robustly impaired both episodic and working memory. Co-administration of CBD at a 2:1 ratio (16 mg CBD with 8 mg THC) did not attenuate any of these THC effects. CBD alone reduced PSI scores, but only in light cannabis users.

Early Cannabis Use and Neurocognitive Risk: A Prospective Functional Neuroimaging Study.

Tervo-Clemmens, Brenden · 2018

At age 12, before any cannabis use, teens who would initiate cannabis by 15 already showed activation differences in frontoparietal (increased) and visual association (decreased) regions, and poorer executive planning scores.

Neuroimaging meta-analysis of cannabis use studies reveals convergent functional alterations in brain regions supporting cognitive control and reward processing.

Yanes, Julio A · 2018

Cannabis users showed decreased activation in the anterior cingulate cortex (linked to cognitive control) and dorsolateral prefrontal cortex (linked to attention).

Neurocognitive Correlates in Driving Under the Influence of Cannabis.

Busardò, Francesco P · 2017

The review synthesized findings from 36 studies on cannabis and driving.

Evidence for the Risks and Consequences of Adolescent Cannabis Exposure.

Levine, Amir · 2017

This comprehensive review examined four neuropsychiatric outcomes most vulnerable to adolescent cannabis exposure: cognition, emotional functioning, psychosis risk, and addiction. The clinical literature showed strong correlations between early, frequent, heavy adolescent cannabis use and poor cognitive and psychiatric outcomes in adulthood.

Deficits in striatal dopamine release in cannabis dependence.

van de Giessen, E · 2017

Eleven severely cannabis-dependent participants (free of all comorbidities, including nicotine use) and 12 healthy controls underwent PET brain scans before and after amphetamine challenge to measure dopamine release. Cannabis-dependent participants had significantly lower dopamine release in the striatum (p = 0.002, effect size 1.48), including the associative striatum (ES = 1.39), sensorimotor striatum (ES = 1.41), and the pallidus (ES = 1.16).

Use of Cannabinoids for Spasticity and Pain Management in MS.

Chohan, Hardeep · 2016

This review synthesized evidence from randomized trials on cannabinoid use for two of the most troubling MS symptoms: spasticity and pain. Several randomized trials provided Class 1 and 2 evidence (the highest levels) supporting cannabinoid products for these indications.

Adult attention-deficit/hyperactivity disorder and its association with substance use and substance use disorders in young men.

Estévez, N · 2016

Researchers examined the relationship between ADHD and substance use in 5,677 Swiss men (average age 20) from a representative cohort study. Men with ADHD were more likely to have used nicotine, cannabis, and other illicit drugs (but not alcohol) at some point.

Acute effects of cocaine and cannabis on response inhibition in humans: an ERP investigation.

Spronk, Desirée B · 2016

In a double-blind, placebo-controlled crossover study, 38 healthy drug-using volunteers received cocaine, cannabis, and placebo in separate sessions and performed a Go/NoGo impulse control task. Cocaine improved performance: faster reaction times, better accuracy, and increased prefrontal NoGo-P3 brain activity (reflecting enhanced evaluative processing).

Is attention deficit/hyperactivity disorder among men associated with initiation or escalation of substance use at 15-month follow-up? A longitudinal study involving young Swiss men.

Vogel, Tanja · 2016

In a large cohort of 5,103 Swiss Army conscripts followed over 15 months, men screening positive for ADHD (4.2%) showed heavier baseline substance use and significantly higher rates of alcohol, tobacco, and cannabis use disorders compared to men without ADHD. However, the pattern over time was nuanced.

Brain Imaging Studies on the Cognitive, Pharmacological and Neurobiological Effects of Cannabis in Humans: Evidence from Studies of Adult Users.

Weinstein, Aviv · 2016

This comprehensive review synthesized 103 structural and functional brain imaging studies of cannabis users published between 2000 and 2016, providing the most complete picture to date of how cannabis affects the human brain. Structural findings: Regular cannabis use was associated with volumetric and tissue changes, particularly in the hippocampus (memory) and amygdala (emotion).

Psychosocial sequelae of cannabis use and implications for policy: findings from the Christchurch Health and Development Study.

Fergusson, David M · 2015

The Christchurch Health and Development Study tracked 1,265 New Zealanders from birth to age 35, providing one of the most comprehensive longitudinal datasets on cannabis outcomes.

How cannabis causes paranoia: using the intravenous administration of ∆9-tetrahydrocannabinol (THC) to identify key cognitive mechanisms leading to paranoia.

Freeman, Daniel · 2015

This was the largest study of intravenous THC, randomizing 121 individuals with existing paranoid ideation to receive THC, placebo, or THC with prior cognitive awareness training.

Protein kinase B (AKT1) genotype mediates sensitivity to cannabis-induced impairments in psychomotor control.

Bhattacharyya, S · 2014

In a double-blind study, healthy occasional cannabis users received either THC or placebo and performed a response inhibition task during brain imaging.

Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment.

Englund, Amir · 2013

In a between-subjects, double-blind design, 48 healthy participants received either 600 mg oral CBD (n=22) or placebo (n=26) before intravenous THC (1.5 mg).

The impact of cannabis use on cognitive functioning in patients with schizophrenia: a meta-analysis of existing findings and new data in a first-episode sample.

Yücel, Murat · 2012

In a surprising finding that contradicts common assumptions, the meta-analysis of 572 patients found that those with a history of cannabis use had superior neuropsychological functioning compared to non-using schizophrenia patients.

Cognition and motor control as a function of Delta9-THC concentration in serum and oral fluid: limits of impairment.

Ramaekers, J G · 2006

Twenty recreational cannabis users participated in a double-blind, placebo-controlled, three-way crossover study with single doses of 0, 250, and 500 micrograms/kg THC by smoking.

The acute effects of cannabinoids on memory in humans: a review.

Ranganathan, Mohini · 2006

This comprehensive review of human studies found that acute THC administration impairs immediate and delayed free recall of information presented after drug administration but does not affect recall of information learned before THC was given. The effects are dose-dependent and delay-dependent, with greater impairment at higher doses and longer delays.

Cannabis and the brain.

Iversen, Leslie · 2003

All known central effects of THC were mediated through CB1 receptors, with particularly high expression on GABAergic interneurons in the hippocampus, amygdala, and cerebral cortex.

Associations Between Youth Marijuana and Alcohol Use, Neurocognitive Performance, and Triple-Network Resting-State Connectivity.

Blyth, Sophia H · 2026

Marijuana use was associated with higher DMN-ECN connectivity (p=0.0066) but no neurocognitive performance changes; alcohol use showed no connectivity changes but was associated with better working memory, flexibility, attention, and executive function — likely confounded by socioeconomic factors..

Personality, not cognition, distinguishes chronic ayahuasca and cannabis users from non-users.

Bouso, José Carlos · 2026

No significant group differences in neuropsychological performance between chronic cannabis users (n=56), ayahuasca users (n=69), and non-users (n=94) matched for age, education, and IQ; personality traits (novelty seeking, impulsive nonconformity) best distinguished cannabis users..

Evaluating Cross-Sectional Associations Between Cannabis Use and Prospective Memory in People with HIV.

Britton, Mark K · 2026

Cannabis use (including regular use) was not significantly associated with prospective memory (MIST) scores in 307 people with HIV after adjusting for confounders; combined recreational-therapeutic motivation showed a nonsignificant trend toward better performance (β=0.28, p=0.067)..

Cannabidiol blood metabolite levels after cannabidiol treatment are associated with broadband EEG changes and improvements in visuomotor and non-verbal cognitive abilities in boys with autism requiring higher levels of support.

Cazares, Christian · 2026

This study analyzed EEG data from 24 boys with autism spectrum disorder (ASD) and higher support needs, drawn from a Phase II clinical trial of pharmaceutical-grade CBD (Epidiolex, up to 20 mg/kg/day). The EEG analysis went beyond traditional approaches, examining both periodic (oscillatory) and aperiodic components of brain activity.

History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.

Ding, Guoyong · 2026

Ever smoking cannabis was associated with increased odds of subjective cognitive complaints across three follow-ups: OR 1.27 (2nd), 1.28 (3rd), 1.30 (4th).

Prenatal Cannabis Exposure Shaping Altered Brain Connectivity: Neural Correlates of Cognitive and Mental Health Variability in Offspring.

Fu, Zening · 2026

Drawing on the massive Adolescent Brain Cognitive Development (ABCD) Study — which enrolled 11,875 children across 22 research sites — this analysis examined how prenatal cannabis exposure (PCE) relates to brain network organization, cognitive performance, and mental health in children. Using resting-state functional MRI and the NeuroMark framework to identify individualized brain connectivity networks, researchers found that children with PCE showed altered patterns of intrinsic connectivity compared to unexposed children.

Working memory capacity predicts cannabis-induced effects on alcohol urge.

Gunn, Rachel L · 2026

Participants with higher working memory (symmetry span task) reported significantly lower alcohol urge after smoking 7.2% THC cannabis vs.

Optimizing antipsychotic dosing for relapse prevention in cannabis-induced psychosis: A nationwide cohort study.

Mustonen, Antti · 2026

Using linked Swedish health registers, researchers identified all individuals with a first diagnosis of cannabis-induced psychosis and conducted a dose-response analysis of oral antipsychotic medications. The analysis modeled antipsychotic exposure as time-dependent across three dose categories (low: <0.6 DDD, moderate: 0.6–<1.4 DDD, high: ≥1.4 DDD) using within-individual comparisons — meaning each person served as their own control across different exposure periods. The primary outcome was hospitalization for any psychotic episode (schizophrenia-spectrum disorder or substance-induced psychosis).

Treatment with a botanical mixture of cannabidiol:Δ9-tetrahydrocannabinol enhances microglial phagocytosis and shapes amyloid plaques in a mouse model of Alzheimer's disease.

Ruiz de Martín Esteban, Samuel · 2026

Chronic treatment (28 days) with CBD:THC (99:1) at 50 mg/kg twice daily in 5xFAD Alzheimer's mice enhanced microglial phagocytic activity and reduced amyloid peptide accumulation in neuritic plaques.

Cannabis Use in a Community-Based Sample of Adults Diagnosed With ADHD: Prevalence, Impact on Symptoms, and Stimulant Side Effects.

Ryan, Jennie E · 2026

Cannabis use was highly prevalent: 75% ever used, 41% past-30-day use.

Child Behavioral Scores Correlate With Prenatal Tobacco and Marijuana Exposure, Sociodemographic Variables and Interactions of Default Mode and Dorsal Attention Networks.

Vishnubhotla, Ramana V · 2026

Using data from 6,674 children in the ABCD Study, researchers examined how prenatal substance exposure related to both behavioral outcomes and brain functional connectivity. Both prenatal tobacco exposure (PTE) and prenatal marijuana exposure were associated with worse behavioral scores on the Child Behavior Checklist.

Association between cannabis consumption and serum Klotho levels in middle-aged U.S. adults: NHANES cross-sectional analysis.

Wang, Li · 2026

Frequent cannabis users had significantly lower Klotho levels than never users (adjusted estimate = -57.94, p = 0.027), with a significant dose-dependent trend (p = 0.022).

The perils of marijuana use in adolescents.

Ward, Savitra · 2026

The pooled prevalence of cannabis use among adolescents ages 12-17 was 11.4% (95% CI: 10.70-12.20%).

Cannabis and nicotine/tobacco co-use and its association with cognitive and neural outcomes: A systematic review.

Yeap, Zac J S · 2026

People who co-used cannabis and nicotine/tobacco showed similar working memory performance, resting-state brain connectivity, and task-based brain activation compared to people without substance use.

Social cognition in young adults who endorse a cannabis use disorder.

Abbott, Gabrielle · 2025

There were no significant effects of CUD on social cognition measures including emotion recognition, emotional differentiation, or immediate/delayed face memory (effect sizes d = 0-0.314).

Cognitive performance in young adults who endorse a cannabis use disorder.

Abbott, Gabrielle · 2025

CUD participants had significantly lower IQ with a strong effect size (p < .001, d = 0.862), driven specifically by lower verbal IQ.

Δ9-Tetrahydrocannabinol Alters Limbic and Frontal Functional Brain Connectomes Among Young Adult Cannabis Users.

Anderson, Zachary · 2025

THC (7.5 mg oral) reduced within-network intrinsic connectivity in corticostriatal circuits and networks associated with sensory systems, interoceptive experiences, and spatial reasoning compared to placebo.

Neurodevelopmental effects of perinatal exposure to cannabis on progeny: A narrative review.

Azubuike, Chidimma Doris · 2025

Children exposed to cannabis prenatally consistently showed higher ADHD risk compared to unexposed children.

Leveraging Genomic Data to Examine the Causal Impact of Alcohol, Tobacco, Cannabis, and Opioid Use on Biological and Cognitive Ageing.

Balbona, Jared V · 2025

Mendelian randomization analyses found significant causal effects of genetic predisposition to tobacco use disorder and smoking quantity on markers of biological, physical, and cognitive aging.

Synaptic Density in Early Stages of Psychosis and Clinical High Risk.

Blasco, M Belen · 2025

Synaptic density (measured by SV2A binding) was significantly lower in first-episode psychosis and clinical high-risk participants compared to healthy controls.

Marijuana use and subjective cognitive decline in middle-aged and older adults: Analysis of the behavioral risk factor surveillance system survey.

Chen, Xiao · 2025

Past-month marijuana users reported higher rates of subjective cognitive decline and SCD-related functional limitations compared to non-users, with a significant dose-response trend (p < 0.001)..

In utero chronic cannabis exposure is associated with lower total brain volume in the first month of postnatal life.

Crume, Tessa L · 2025

Studying prenatal cannabis exposure is extremely difficult because most pregnant cannabis users also use tobacco, alcohol, or other substances, making it nearly impossible to isolate cannabis's independent effects.

Impulsivity behaviors and white matter mediate the relationship between genetic risk for cannabis use disorder and early cannabis use in adolescents.

Cupertino, Renata Basso · 2025

Higher genetic risk for CUD was associated with greater cannabis exposure, more novelty/sensation seeking, higher impulsivity, and lower white matter integrity from age 14.

A randomized clinical trial of low-dose cannabis extract in Alzheimer's disease.

Cury, Rafael de Morais · 2025

Patients receiving low-dose THC-CBD extract (0.350 mg THC + 0.245 mg CBD daily) had significantly higher Mini-Mental State Exam scores at week 26 compared to placebo..

Methylomic signature of current cannabis use in two first-episode psychosis cohorts.

Dempster, Emma L · 2025

Current cannabis use was associated with differential methylation at a site in the CAVIN1 gene, independent of tobacco effects.

Associations of maternal peripregnancy cannabis use with behavioral and developmental outcomes in children with and without symptoms of autism spectrum disorder: Study to Explore Early Development.

DiGuiseppi, Carolyn · 2025

Preconception-only cannabis use was associated with more aggressive behavior, emotional reactivity, and sleep problems specifically in children with ASD symptoms, but not in children without.

Cognitive presentation at psychosis onset through premorbid deterioration and exposure to environmental risk factors.

Ferraro, Laura · 2025

Among 802 first-episode psychosis patients, those in the "deteriorating" cognitive cluster had higher cannabis exposure than the "intermediate" cluster with identical IQ, and all patient clusters had higher environmental risk scores than the 1,263 community controls..

Neural Signatures of Cannabis Use: Reversing Cognitive Aging via Whole-Brain Functional Network Connectivity.

Fu, Zening · 2025

Cannabis use and healthy aging were associated with overlapping brain network configurations, particularly between subcortical-sensorimotor and subcortical-cerebellar regions, but with significantly reversed effects.

Neurocognitive Dysfunctions in People with Concurrent Cannabis Use and Opioid Dependence: A Cross-Sectional, Controlled Study.

Ghosh, Abhishek · 2025

The OD+CD group completed significantly fewer categories on the Wisconsin Card Sorting Test than healthy controls and had more non-perseverative errors.

Effects of legal-market cannabis and alcohol on verbal learning and memory.

Gowin, Joshua L · 2025

Sixty adults who regularly used both alcohol and cannabis completed two lab sessions: one with alcohol alone and one with alcohol plus legal-market cannabis.

Association Between Cannabis Use and Neuropsychiatric Disorders: A Two-sample Mendelian Randomization Study.

Guo, Wei · 2025

Using two-sample Mendelian randomization with GWAS data, the study found genetically predicted lifetime cannabis use was associated with increased risk of Parkinson's disease (OR=1.78, 95% CI: 1.03-3.08) and ADHD in women (OR=1.65, 95% CI: 1.05-2.59).

A Systematic Review: Investigating Biomarkers of Anhedonia and Amotivation in Depression and Cannabis Use.

Hinckley, Jesse D · 2025

Across 46 articles, brain regions most frequently associated with anhedonia across neuroimaging studies were the anterior cingulate cortex, nucleus accumbens, and medial prefrontal cortex, which are the same regions implicated in cannabis-related reward processing deficits.

Chronic Δ9-tetrahydrocannabinol exposure in adolescent nonhuman primates: persistent abnormalities in economic demand and brain functional connectivity.

Kangas, Brian D · 2025

Adolescent monkeys treated daily with THC for 6 months showed persistent alterations in medial orbitofrontal cortex, caudate, and ventral striatum functional connectivity that lasted after discontinuation.

Cannabis Perturbs Dynamic Brain States.

Lege, Katharina S · 2025

This neuroimaging trial used a sophisticated approach—dynamic functional connectivity analysis—to examine how vaporized cannabis affects brain network organization in real time.

Abnormal Cortical Thickness Development in Young Adults With Heavy Cannabis Use: A Longitudinal Study.

Li, Wei · 2025

At three-year follow-up, heavy cannabis users showed significant cortical thinning in the left lateral orbitofrontal cortex compared to both their own baseline and control subjects.

Sex differences in the acute effects of cannabis on human cognition: A systematic review.

Matheson, Justin · 2025

Of 29 studies meeting criteria, only 6 (20.7%) found statistical evidence of sex differences in acute cognitive effects, representing just 8 of 216 cognitive outcomes tested (3.7%).

A randomized, placebo-controlled, double-blind, pilot study of cannabis-related driving impairment assessed by driving simulator and self-report.

Meda, Shashwath A · 2025

In a controlled simulator study, cannabis administration led to measurable driving impairment including lane weaving and reaction time delays, even when participants self-reported feeling capable of driving..

The effects of orally ingested Delta-9-Tetrahydrocannabinol on drivers' hazard perception and risk-taking behaviours: A within-subjects study of medicinal cannabis users.

Mieran, Taren · 2025

Among 41 medicinal cannabis users, oral THC did not significantly impair hazard perception skill, but participants chose slower speeds and longer following distances after consumption.

Understanding the Relationships between ADHD Symptoms and Cannabis-Related Consequences among Young Adults.

Minister, Claire · 2025

In 160 young adult cannabis users, inattentive symptoms directly predicted occupational/academic problems, self-care deficits, and blackouts from cannabis, independent of consumption amount.

Cognitive and behavioral pathways from prenatal cocaine exposure to regular marijuana use during emerging adulthood.

Minnes, Sonia · 2025

Among 310 participants tracked from birth, prenatal cocaine exposure predicted poorer executive function at age 12 (beta=0.19), which predicted substance use at 15 (beta=0.21), which strongly predicted regular marijuana use at 21 (beta=0.70).

Influence of recent cannabis use on altered spectral entropy modulation and connectivity strength in patients with psychosis.

Molina, Vicente · 2025

Both cannabis-using and non-using psychosis patients showed impaired spectral entropy modulation and elevated connectivity strength compared to 86 healthy controls.

Age-Related Effects of Cannabis and Cannabinoids on Brain and Behavior.

Murray, Conor H · 2025

Recent epidemiological data suggest a potential reversal in escalating cannabis use rates among pregnant women and adolescents, but use among older adults continues to climb with low risk perception.

Cannabis use in adolescence and young adulthood and its effects on brain structure and function: a scoping review.

Nosko, Lilith · 2025

Of 99 studies meeting inclusion criteria (from 3,901 initially screened), 84 (85%) found differences in brain structure, function, and/or metabolite concentrations in cannabis users aged 14-25 compared to non-using controls.

The Effects of THC and Nicotine on Attention: A Narrative Review.

Oleszak, Kennedy · 2025

Cannabis impairs selective attention and creates attentional bias toward cannabis cues.

Naturalistic investigation of cannabis strains varying in THC and CBD ratios and verbal recognition memory.

Paulich, Katie N · 2025

The idea that CBD might counteract THC's cognitive effects has been a popular hypothesis in cannabis research—and a selling point for balanced THC:CBD products.

Caregiver-reported non-seizure and seizure outcomes with cannabidiol and clobazam in patients aged ≥2 years with Lennox-Gastaut syndrome or Dravet syndrome: A subgroup analysis of the BECOME survey.

Perry, M Scott · 2025

Caregivers reported improvements across multiple domains: seizure frequency (87%), severity (81%), alertness/cognition/executive function (84%), language/communication in non-verbal patients (81%) and verbal patients (76%), emotional/social functioning (79%), daily activities (56%), physical functioning (44%), and sleep (56%).

Longitudinal Associations Between Cannabis Use during Pregnancy and Child Cognitive, Motor, and Language Development at 2 Years Old.

Pleau, Justine · 2025

In 1,489 mother-infant dyads from the 3D prospective cohort, prenatal cannabis use (2.6% of women) showed no significant associations with cognitive (B=0.016), fine motor (B=0.029), gross motor (B=0.060), or language development (B=0.200) at age 2.

The Relationship Between Cannabis Use and Schizophrenia As a Risk Factor or For Its Therapeutic Potential: A Systematic Review of Evidence.

Rajput, Jaisingh · 2025

The cannabis-schizophrenia relationship is one of the most polarized debates in psychiatric research.

Chronic Δ9-tetrahydrocannabinol exposure during adolescence is associated with persistent behavioural tolerance in adult nonhuman primates.

Razavi, Yasaman · 2025

Nonhuman primates treated daily with THC during adolescence (6 months at low or high doses) and tested approximately one year later as adults showed persistent behavioral tolerance.

High-Intensity Exercise and Hippocampal Integrity in Adults With Cannabis Use Disorder: A Randomized Clinical Trial.

Richardson, Karyn E · 2025

Hippocampal integrity (a composite of brain volume, structural connectivity, and neurochemistry) did not improve after 12 weeks of HIIT compared to strength training in adults with moderate to severe CUD.

The effects of cannabis on mind-wandering.

Safati, Adrian Berk · 2025

In a three-session ABA design (abstinent-cannabis-abstinent), cannabis use was associated with a large increase in spontaneous mind-wandering during a metronome timing task.

Validation of the Spanish version of the multifaceted empathy test: comparison between cannabis use effects and controls in social cognition.

Sainz-Cort, Alberto · 2025

116 participants from a Cannabis Social Club completed empathy tests under the effects of cannabis and were compared to 86 sober university students.

Cannabidiol and cognition: a literature review of human randomized controlled trials.

Singh, Jyotpal · 2025

In healthy participants, CBD showed some effects on cognitive function and sleep quality with various dosing strategies.

A naturalistic examination of the effects of chronic and acute cannabis use on cognition and perceived symptoms of attention-deficit/hyperactivity disorder.

Stueber, Amanda M · 2025

Cannabis users with ADHD reported subjective improvement in ADHD symptoms after acute cannabis use.

History of cannabis use and cognitive function in older adults: findings from the UK biobank.

Sznitman, Sharon R · 2025

Cross-sectionally, lifetime cannabis users (17% of sample) performed better in attention (B=0.071), executive function (B=0.047), processing speed (B=0.363), visual memory (B=0.062), and working memory (B=0.181).

Longitudinal Neurocognitive Trajectories in a Large Cohort of Youth Who Use Cannabis: Combining Self-Report and Toxicology.

Wade, Natasha E · 2025

This is the most comprehensive longitudinal study to date on adolescent cannabis use and cognitive development, drawing from the ABCD Study—a landmark NIH-funded project tracking brain development in American children. The primary analysis followed 11,036 participants from ages 9 to 17, combining self-reported substance use with objective toxicological testing (hair, urine, breath, oral fluid).

Effects of cannabis smoke and oral Δ9THC on cognition in young adult and aged rats.

Zequeira, Sabrina · 2025

Chronic oral THC enhanced prefrontal cortex-dependent working memory in aged rats of both sexes without affecting young adults.

The Impact of Cannabis Use on Cognition in People with HIV: Evidence of Function-Dependent Effects and Mechanisms from Clinical and Preclinical Studies.

Ayoub, Samantha M · 2024

The review found little evidence supporting harmful effects of cannabis on cognition in people with HIV.

The interaction between cannabinoids and long-term synaptic plasticity: A survey on memory formation and underlying mechanisms.

Azarfarin, Maryam · 2024

Evidence on cannabinoid effects on LTP and memory is contradictory.

Alterations in self-reported sensory gating and interoception in individuals frequently using cannabis.

Bloomer, Bess F · 2024

Cannabis users reported impaired sensory gating across subscales (d=0.37-0.44, all p<0.05) and heightened affect-related interoceptive awareness (d=0.21-0.61, all p<0.05) compared to non-users.

Association between cannabis use disorder and greater apathy in adults with HIV.

Britton, Mark K · 2024

Current CUD was associated with greater apathy (beta = 2.13, p = 0.018) compared to cannabis users without CUD history.

Effects of acute cannabis inhalation on reaction time, decision-making, and memory using a tablet-based application.

Brooks-Russell, Ashley · 2024

Occasional users showed significant decrements in reaction time and short-term memory after smoking cannabis.

Prenatal THC exposure drives sex-specific alterations in spatial memory and hippocampal excitatory/inhibitory balance in adolescent rats.

Castelli, Valentina · 2024

Prenatal THC exposure caused sex-specific disruption in spatial memory retrieval and flexibility.

The Impact of Childhood Mental Health and Substance Use on Methylation Aging Into Adulthood.

Clark, Shaunna L · 2024

Weekly cannabis use was significantly associated with accelerated DNA methylation aging (b=1.665, p=.005), as were years of weekly use (b=0.718, p=.012) and depressive symptoms (b=0.314, p=.014).

The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study.

Hall, Daniel · 2024

In a three-condition crossover trial (THC, THC+CBD, placebo), participants showed an attentional bias away from cannabis cues on placebo.

Using Task-fMRI to Explore the Relationship Between Lifetime Cannabis Use and Cognitive Control in Individuals With First-Episode Schizophrenia.

Lesh, Tyler A · 2024

First-episode schizophrenia patients with cannabis history (FES+CAN, n=48) showed higher cognitive control performance and higher dorsolateral prefrontal cortex (DLPFC) activation during task-based fMRI compared to patients without cannabis history (FES-CAN, n=28).

Light Cannabis Use and the Adolescent Brain: An 8-years Longitudinal Assessment of Mental Health, Cognition, and Reward Processing.

Macedo, Inês · 2024

Teens who used cannabis weekly or monthly between ages 19 and 22 showed more conduct problems than non-users, but no differences in cognitive performance or reward-related brain activity.

White matter alterations associated with chronic cannabis use disorder: a structural network and fixel-based analysis.

Maleki, Suzan · 2024

Compared to 38 healthy controls, 56 individuals with CUD had significantly increased structural connectivity across 9 brain connections involving the right parietal cortex and regions including left orbitofrontal cortex, temporal pole, hippocampus, and putamen.

A systematic review of oculomotor deficits associated with acute and chronic cannabis use.

Manning, Brooke · 2024

Across 20 studies, acute THC consumption increased saccadic latency, reduced accuracy, and impaired inhibitory control.

A randomised, placebo-controlled, double blind, crossover trial on the effect of a 20:1 cannabidiol: Δ9-tetrahydrocannabinol medical cannabis product on neurocognition, attention, and mood.

Manning, Brooke · 2024

A sublingual dose of CannEpil (100mg CBD, 5mg THC) impaired visuospatial working memory and delayed pattern recognition compared to placebo, but largely preserved mood.

The effects of cannabis abstinence on cognition and resting state network activity in people with multiple sclerosis: A preliminary study.

Meza, Cecilia · 2024

The cannabis withdrawal group showed increased activation at day 28 in the left posterior cingulate, right angular gyrus, left hippocampus, and right medial prefrontal cortex compared to baseline.

Cells and Molecules Underpinning Cannabis-Related Variations in Cortical Thickness during Adolescence.

Navarri, Xavier · 2024

In mice, THC exposure caused spine loss and reduced dendritic complexity in frontal cortex pyramidal cells.

Childhood executive control and adolescent substance use: Mediation via parent-child relationship quality.

Patwardhan, Irina · 2024

Preschool executive control did not directly predict adolescent cannabis, e-cigarette, or alcohol use.

Prenatal tobacco, tobacco-cannabis coexposure, and child emotion regulation: The role of child autonomic functioning and sensitive parenting.

Perry, Kristin J · 2024

Direct effects from prenatal exposure on early school age emotion regulation were not significant.

Longitudinal Pathways From Maltreatment to Substance Use Through Delay Discounting During Adolescence and Into Young Adulthood.

Peviani, Kristin M · 2024

Using developmental cascade models, neglect (but not abuse) predicted elevated delay discounting, which in turn predicted increased cannabis use across ages 14-18.

Implications of Prenatal Cannabis Exposure on Childhood Neurodevelopmental Outcomes: A Summary of the Clinical Evidence.

Sheffield, Sydney Mei · 2024

Limited but consistent data showed associations between prenatal cannabis exposure and increased startles and difficulty consoling in newborns, memory and verbal reasoning challenges in early childhood, diminished academic performance, and inattention, hyperactivity, and aggression in early childhood..

Prenatal tobacco and tobacco-cannabis co-exposure: Relationship with attention and memory in middle childhood.

Shisler, Shannon · 2024

Prenatal tobacco exposure was associated with increased impulsive responding on sustained attention tasks, particularly when exposure occurred in the first trimester.

Patterns of substance use and initiation timing in adults with substance abuse: a comparison between those with and without attention deficit hyperactivity disorder.

Vaziri-Harami, Roya · 2024

The ADHD group had a lower age of onset for substance use.

Investigating sex differences and age of onset in emotion regulation, executive functioning, and cannabis use in adolescents and young adults.

Wade, Natasha E · 2024

Greater past 6-month cannabis use was associated with poorer Emotional Stroop Congruent Accuracy (p=0.0004) and List Sorting Working Memory performance (p=0.02, marginally significant after correction).

Cannabis use and neurocognitive performance at 13-14 Years-Old: Optimizing assessment with hair toxicology in the Adolescent brain cognitive development (ABCD) study.

Wade, Natasha E · 2024

Cannabis-using teens scored lower on episodic memory tasks, and higher THC metabolite levels in hair correlated with poorer verbal ability, inhibitory control, working memory, and episodic memory..

Cannabidiol, a plant-derived compound, is an emerging strategy for treating cognitive impairments: comprehensive review of randomized trials.

Yndart Arias, Adriana · 2024

Nine of 16 outcomes across 14 trials showed CBD improved anxiety and cognition.

Genetic support of a causal relationship between cannabis use and educational attainment: a two-sample Mendelian randomization study of European ancestry.

Chen, Dongze · 2023

Bidirectional Mendelian randomization found genetic liability to cannabis use disorder was associated with 1.2 fewer months of education (P=0.0008).

Can inhaled cannabis users accurately evaluate impaired driving ability? A randomized controlled trial.

Hartley, Sarah · 2023

One of the most important questions in cannabis and driving is whether users can tell when they're too impaired to drive.

Genome-wide DNA methylation association study of recent and cumulative marijuana use in middle aged adults.

Nannini, Drew R · 2023

At examination year 15 (n = 1,023), 22 and 31 methylation markers were associated with recent and cumulative marijuana use.

Towards a New Dynamic Interaction Model of Adolescent CUD Manifestation, Prevention, and Treatment: A Narrative Review.

Oosten, Wesley · 2023

The review adapts Zinberg's drug-set-setting framework to propose CUD in adolescents develops through multiple interacting feedback loops.

The Impact of Cannabis Use on Adolescent Neurodevelopment and Clinical Outcomes Amidst Changing State Policies.

Ross, Jennifer A · 2023

The adolescent brain is especially vulnerable because the prefrontal cortex (responsible for impulse control and executive functions) is not fully mature until the mid-twenties.

Alcohol & cannabinoid co-use: Implications for impaired fetal brain development following gestational exposure.

Rouzer, Siara Kate · 2023

Both alcohol and cannabinoids independently impact fetal neurodevelopment with lifelong consequences.

Prenatal THC exposure induces long-term, sex-dependent cognitive dysfunction associated with lipidomic and neuronal pathology in the prefrontal cortex-hippocampal network.

Sarikahya, Mohammed H · 2023

Both sexes showed long-term cognitive deficits and hyperactive prefrontal pyramidal neurons.

Cannabidiol and brain function: current knowledge and future perspectives.

Schouten, Moniek · 2023

CBD has documented therapeutic effects for epileptic seizures, psychosis, anxiety, neuropathic pain, and inflammation.

Impact of Adolescent Cannabis Use on Neurocognitive and Brain Development.

Scott, J Cobb · 2023

Converging evidence shows that ongoing, frequent cannabis use in adolescence is associated with small reductions in cognitive functioning.

An exploratory follow-up study of cannabis use and decision-making under various risk conditions within adolescence.

Thompson, Erin L · 2023

Baseline performance on the Game of Dice Task (explicit risk decision-making) predicted greater escalation in cannabis use frequency and cannabis-related problems over 2 years.

Cannabis Use Associations with Adverse Psychosocial Functioning among North American College Students.

Vidal, Carol · 2023

Cannabis use among college-enrolled young adults was associated with adverse psychosocial outcomes across multiple domains.

Clouding Up Cognition? Secondhand Cannabis and Tobacco Exposure Related to Cognitive Functioning in Youth.

Wade, Natasha E · 2023

Secondhand cannabis and tobacco exposure in youth were independently associated with lower cognitive performance across multiple domains, suggesting passive exposure may carry cognitive risks during brain development..

Is the effect of cognitive reserve in longitudinal outcomes in first-episode psychoses dependent on the use of cannabis?

Amoretti, Silvia · 2022

Cognitive reserve was associated with better cognitive performance regardless of cannabis use.

The effects of acute Cannabis smoke or Δ9-THC injections on the trial-unique, nonmatching-to-location and five-choice serial reaction time tasks in male Long-Evans rats.

Barnard, Ilne L · 2022

High-THC cannabis smoke and THC injections impaired working memory on the TUNL task but had no effect on attention, impulsivity, or perseveration on the 5-CSRTT.

Anandamide Hydrolysis Inhibition Reverses the Long-Term Behavioral and Gene Expression Alterations Induced by MK-801 in Male Rats: Differential CB1 and CB2 Receptor-Mediated Effects.

Bauminger, Hagar · 2022

The anandamide hydrolysis inhibitor URB597, given in late adolescence, reversed both novel object recognition deficits (via CB2 receptors) and social interaction abnormalities (via CB1 receptors) induced by early-adolescence MK-801 administration, while also normalizing glutamate and GABA marker expression in the prefrontal cortex..

A naturalistic study of orally administered vs. inhaled legal market cannabis: cannabinoids exposure, intoxication, and impairment.

Bidwell, L Cinnamon · 2022

Flower users consumed an average of 51.25 mg THC vs.

Perceived effects of cannabis: Generalizability of changes in driving performance.

Burt, Thomas S · 2022

Subjective perceptions of cannabis impairment significantly predicted driving performance measures (lane position, speed control) beyond the effect of THC dose.

Prenatal cannabis exposure predicts attention problems, without changes on fMRI in adolescents.

Cioffredi, Leigh-Anne · 2022

Compared to both control groups, children with prenatal cannabis exposure (PCE) had significantly higher attention problems, externalizing, and total problem scores on the Child Behavior Checklist.

Differences in alcohol and cannabis use amongst substance use disorder patients with and without comorbid attention-deficit/hyperactivity disorder.

Coetzee, Corné · 2022

The SUD+ADHD group showed increased cannabis consumption compared to the SUD-only group.

Changes in brain structure and function following chronic exposure to inhaled vaporised cannabis during periadolescence in female and male mice: A multimodal MRI study.

Coleman, James R · 2022

Female mice showed altered fractional anisotropy and apparent diffusion coefficient (measures of brain microstructure) in forebrain and hindbrain.

Clinical practice guideline on pharmacological and psychological management of adult patients with attention deficit and hyperactivity disorder and comorbid substance use.

Cunill, Ruth · 2022

For ADHD with cannabis use disorder: atomoxetine is weakly recommended to improve ADHD symptoms but weakly recommended against reducing cannabis use.

Latent inhibition, aberrant salience, and schizotypy traits in cannabis users.

Dawes, Christopher · 2022

Current cannabis use was associated with higher "disorganized" and "cognitive-perceptual" schizotypy scores and higher aberrant salience inventory scores.

Long-term effects of prenatal cannabis exposure: Pathways to adolescent and adult outcomes.

De Genna, Natacha M · 2022

Across longitudinal studies, prenatal cannabis exposure showed remarkably consistent associations with externalizing behaviors like delinquency and substance use that persisted into adulthood.

The association between cannabis use and facial emotion recognition in schizophrenia, siblings, and healthy controls: Results from the EUGEI study.

Fusar-Poli, Laura · 2022

Better facial emotion recognition was associated with lifetime regular cannabis use across all three groups: schizophrenia patients (B=1.36), siblings (B=2.17), and healthy controls (B=3.10).

Surface-based brain morphometry in schizophrenia vs. cannabis-induced psychosis: A controlled comparison.

Ghosh, Abhishek · 2022

Schizophrenia with heavy cannabis use (SZC) showed the lowest cortical thickness, depth, and gyrification, followed by cannabis-induced psychosis (CIP), then healthy controls.

Multimodal MRI data fusion reveals distinct structural, functional and neurochemical correlates of heavy cannabis use.

Hirjak, Dusan · 2022

Two transmodal components significantly differed between heavy cannabis users and controls.

Effects of High-Potency Cannabis on Psychomotor Performance in Frequent Cannabis Users.

Karoly, Hollis C · 2022

Peak psychomotor impairment occurred immediately after cannabis use, with significant recovery by one hour post-use.

Persistent sexually dimorphic effects of adolescent THC exposure on hippocampal synaptic plasticity and episodic memory in rodents.

Le, Aliza A · 2022

Adolescent THC exposure produced selective, lasting deficits in synaptic plasticity in two hippocampal pathways, primarily in females.

Effects of cannabidiol on simulated driving and cognitive performance: A dose-ranging randomised controlled trial.

McCartney, Danielle · 2022

Non-inferiority analyses established that CBD at 15, 300, and 1,500 mg did not impair driving performance beyond a threshold equivalent to 0.05% blood alcohol.

Cannabis use as a moderator of cognitive behavioral therapy for insomnia.

Miller, Mary Beth · 2022

Among 56 young adult binge drinkers with insomnia, 46% used cannabis during the treatment phase.

Adolescents are more sensitive than adults to acute behavioral and cognitive effects of THC.

Murray, Conor H · 2022

Adolescents (18-20) showed dose-dependent impairments in reaction time, response accuracy, and time perception with THC (7.5 and 15 mg) that adults (30-40) did not exhibit.

Comparison of the effects of alcohol and cannabis on visual function and driving performance. Does the visual impairment affect driving?

Ortiz-Peregrina, Sonia · 2022

Both alcohol (300 ml and 450 ml wine) and cannabis significantly impaired visual function scores.

Bayesian causal network modeling suggests adolescent cannabis use accelerates prefrontal cortical thinning.

Owens, Max M · 2022

All Bayesian causal network algorithms strongly suggested a directional relationship from adolescent cannabis use to accelerated cortical thinning in the prefrontal cortex, even after accounting for demographics, psychopathology, childhood adversity, and other substance use..

Associations between cognition and polygenic liability to substance involvement in middle childhood: Results from the ABCD study.

Paul, Sarah E · 2022

Polygenic risk for lifetime cannabis use was positively associated with all three cognitive facets: general ability, executive function, and learning/memory (Bs ≥ 0.045, qs ≤ 0.044).

Pattern of predictive features of continued cannabis use in patients with recent-onset psychosis and clinical high-risk for psychosis.

Penzel, Nora · 2022

Clinical interview data alone predicted continued cannabis use with 73% accuracy in 109 recent-onset psychosis patients.

Shared Genetic Etiology between Cortical Brain Morphology and Tobacco, Alcohol, and Cannabis Use.

Rabinowitz, Jill A · 2022

Eight significant negative genetic correlations were found between brain measures and substance use, including between alcohol consumption and cortical thickness.

The associations of cannabis and methamphetamine use with cognitive performance over the first 2 years of treatment in schizophrenia spectrum disorders.

Scheffler, Freda · 2022

In 81 patients with first-episode schizophrenia spectrum disorders treated over 24 months, positive methamphetamine tests predicted less cognitive improvement, but positive cannabis tests did not..

Neural responses to reward anticipation and feedback in adult and adolescent cannabis users and controls.

Skumlien, Martine · 2022

Cannabis users and controls had similar neural responses during reward anticipation and in reward-related brain regions during feedback.

Self-Reported Effects of Cannabis on ADHD Symptoms, ADHD Medication Side Effects, and ADHD-Related Executive Dysfunction.

Stueber, Amanda · 2022

Participants with ADHD reported cannabis had acute beneficial effects on many ADHD symptoms including hyperactivity and impulsivity.

Is in-utero exposure to cannabis associated with the risk of attention deficit with or without hyperactivity disorder? A cohort study within the Quebec Pregnancy Cohort.

Tchuente, Vanina · 2022

After adjusting for potential confounders, no significant association was found between in-utero cannabis exposure (occasional: OR 1.22, 95% CI 0.63-2.19; regular: OR 1.22, 95% CI 0.42-2.79) and the risk of ADHD in children..

Separate and combined effects of alcohol and cannabis on mood, subjective experience, cognition and psychomotor performance: A randomized trial.

Wickens, Christine M · 2022

Cannabis increased tension-anxiety, confusion, euphoria, and sedation ratings but had minimal impact on cognitive test scores.

The effect of medical cannabis on cognitive functions: a systematic review.

Wieghorst, Anders · 2022

Of 23 included studies (917 total participants), 15 found non-significant effects on cognition, 6 found impairments, 1 found improvement, and 1 found improvement after withdrawal.

Dos(e)Age: Role of Dose and Age in the Long-Term Effect of Cannabinoids on Cognition.

Zamberletti, Erica · 2022

Prenatal and adolescent cannabinoid exposure consistently led to long-term cognitive deficits in animal models, while exposure in aged animals showed potential beneficial effects on cognition.

Cannabinoids for the treatment of dementia.

Bosnjak Kuharic, Dina · 2021

Across four RCTs testing natural and synthetic THC, there was very low certainty evidence of minimal effect on cognition (1.1-point sMMSE difference) and low certainty evidence of minimal effect on behavioral symptoms (-1.97 NPI difference).

Are psychotic-like experiences related to a discontinuation of cannabis consumption in young adults?

Daedelow, Laura S · 2021

Mean cannabis use increased from age 19 to 22.

Cannabis Use, Schizotypy and Kamin Blocking Performance.

Dawes, Christopher · 2021

Neither lifetime nor current cannabis use was associated with changes in Kamin blocking scores.

Are Schizophrenic disorders with or without early cannabis use neurobiologically distinct disease entities? A meta-analysis of magnetic resonance imaging studies.

De Peri, Luca · 2021

Both schizophrenia patients with cannabis use (n=227) and without (n=238) showed reduced whole brain, total grey matter, and hippocampal volumes compared to healthy controls (n=366).

Duration of Neurocognitive Impairment With Medical Cannabis Use: A Scoping Review.

Eadie, Lauren · 2021

Across all seven included studies, cognitive performance declined mostly in a THC dose-dependent manner with steady resolution in the hours following administration.

Exploring the Relationship Between ADHD Symptoms and Daily Cannabis Consequences in Emerging Adulthood: The Role of Cannabis Motives.

Goldstein, Abby L · 2021

Higher past-6-month ADHD symptoms predicted more daily cannabis consequences overall.

Effectiveness of attentional bias modification training as add-on to regular treatment in alcohol and cannabis use disorder: A multicenter randomized control trial.

Heitmann, Janika · 2021

No significant differences emerged between the ABM group and control groups on any measure: substance use, craving, relapse rates, attentional bias, depression, anxiety, or stress, either at post-test or at 6- and 12-month follow-ups.

The Influence of Cannabis and Nicotine Co-use on Neuromaturation: A Systematic Review of Adolescent and Young Adult Studies.

Hernandez Mejia, Margie · 2021

Cannabis and nicotine showed independent negative cognitive effects, but when used together, nicotine appeared to mask some cannabis-related cognitive deficits.

Psychiatric Comorbidity and Addiction Severity Differences in Patients With ADHD Seeking Treatment for Cannabis or Cocaine Use Disorders.

Martínez-Luna, Nieves · 2021

In multivariate analysis, the cannabis group had significantly higher rates of lifetime anxiety disorder and younger age at onset of any substance use disorder.

Behavioral and Cognitive Differences in Early Childhood related to Prenatal Marijuana Exposure.

Murnan, Aaron W · 2021

Compared to non-exposed children, those with prenatal marijuana exposure had significantly more sleep-related problems, withdrawal symptoms, externalizing problems including aggressive behaviors and oppositional defiant behaviors at age 3.5.

Cannabis Use, Age of Initiation, and Neurocognitive Performance: Findings from a Large Sample of Heavy Drinking Emerging Adults.

Parlar, Melissa · 2021

Daily cannabis users showed significantly poorer working memory, more impulsive delay discounting, and greater ADHD symptom endorsement compared to non-users.

Cannabis use-related working memory deficit mediated by lower left hippocampal volume.

Paul, Subhadip · 2021

Higher frequency of cannabis use was associated with lower working memory scores and smaller bilateral hippocampal volumes.

Daily, but not occasional, cannabis use is selectively associated with more impulsive delay discounting and hyperactive ADHD symptoms in binge-drinking young adults.

Petker, Tashia · 2021

Daily cannabis users showed significantly more impulsive delay discounting and more hyperactive-impulsive ADHD symptoms compared to both occasional users and non-users.

Symptomatology and neurocognition among first-episode psychosis patients with and without cannabis use in the three months prior to first hospitalization.

Pope, Leah G · 2021

Cannabis users had significantly lower anhedonia-asociality scores (10.7 vs 12.1, p=0.023) but more severe delusions (19.3 vs 15.9, p=0.005) and bizarre behavior (p=0.01).

Sex Differences in Neuropsychological Functioning are Domain-Specific in Adolescent and Young Adult Regular Cannabis Users.

Savulich, George · 2021

Male cannabis users had poorer visual recognition memory while female users showed worse attention and executive functioning (medium to large effect sizes), with earlier initiation and heavier use more strongly linked to attention deficits in females and memory/learning deficits in males..

Assessment of cognitive and psychomotor impairment, subjective effects, and blood THC concentrations following acute administration of oral and vaporized cannabis.

Spindle, Tory R · 2021

High-dose oral and vaporized cannabis impaired cognitive and psychomotor performance, but field sobriety tests showed little sensitivity to cannabis-induced impairment.

Intoxication by a synthetic cannabinoid (JWH-018) causes cognitive and psychomotor impairment in recreational cannabis users.

Theunissen, Eef L · 2021

At 75 microg/kg, JWH-018 impaired motor coordination (CTT), attention (DAT and SST), memory (SMT), lowered speed-accuracy efficiency (MFFT), and slowed response speed.

Cerebellar thickness changes associated with heavy cannabis use: A 3-year longitudinal study.

Wang, Yanpei · 2021

Both lobule VI and Crus I had higher rates of thickness increase in cannabis users than controls.

Is the Adolescent Brain at Greater Vulnerability to the Effects of Cannabis? A Narrative Review of the Evidence.

Blest-Hopley, Grace · 2020

Adolescent cannabis users show altered functional connectivity within established brain circuits, with largely increased functional activation compared to controls.

A Systematic Review of Human Neuroimaging Evidence of Memory-Related Functional Alterations Associated with Cannabis Use Complemented with Preclinical and Human Evidence of Memory Performance Alterations.

Blest-Hopley, Grace · 2020

Twelve fMRI studies showed cannabis users had altered brain activation during memory tasks compared to non-users.

Cannabis Use in Adolescence: A Review of Neuroimaging Findings.

Chye, Yann · 2020

Adolescent cannabis users showed alterations mainly in frontal and parietal regions and associated brain activation related to inhibitory control, reward, and memory.

Maternal cannabis use in pregnancy and child neurodevelopmental outcomes.

Corsi, Daniel J · 2020

Autism spectrum disorder incidence was 4.00 per 1,000 person-years among cannabis-exposed children vs.

Characterizing psychosis-relevant phenomena and cognitive function in a unique population with isolated, chronic and very heavy cannabis exposure.

D'Souza, Deepak Cyril · 2020

Cases averaged 30,000+ lifetime cannabis exposures with no other substance use.

Different Effects of Cannabis Abuse on Adolescent and Adult Brain.

Dhein, Stefan · 2020

THC activation of CB1 receptors diminishes neuronal growth factor production and affects signaling cascades involved in synapse formation.

Update on the developmental consequences of cannabis use during pregnancy and lactation.

Grant, Kimberly S · 2020

Prenatal cannabis exposure was not associated with a unique pattern of birth defects or reductions in global IQ, but specific cognitive skills (attention and memory) were negatively affected.

Acute Effects of Cannabis Concentrate on Motor Control and Speed: Smartphone-Based Mobile Assessment.

Hitchcock, Leah N · 2020

Arm speed slowed immediately and remained impaired at 1 hour post-use.

Altered Corticolimbic Control of the Nucleus Accumbens by Long-term Δ9-Tetrahydrocannabinol Exposure.

Hwang, Eun-Kyung · 2020

Long-term THC weakened prefrontal cortex glutamate input to the nucleus accumbens shell and strengthened input from the basolateral amygdala and ventral hippocampus.

ADHD Is Highly Prevalent in Patients Seeking Treatment for Cannabis Use Disorders.

Notzon, Daniel P · 2020

Among 99 adults seeking cannabis use disorder treatment, ADHD prevalence was estimated at 34% (CAARS), 45% (WURS), 46% (ASRS), or 36% (WURS+CAARS combined).

Does cannabis use predict psychometric schizotypy via aberrant salience?

O'Tuathaigh, Colm M P · 2020

Among 910 students, frequent cannabis use predicted higher scores on positive and disorganized schizotypy subscales.

The effects of Cannabidiol (CBD) and Delta-9-Tetrahydrocannabinol (THC) on the recognition of emotions in facial expressions: A systematic review of randomized controlled trials.

Rossi, Giordano Novak · 2020

Across 7 experiments (170 total participants), THC (7.5-15 mg) had no effect in 3 experiments and reduced facial emotion recognition in 3 others.

Individuals with psychosis and a lifetime history of cannabis use show greater deficits in emotional experience compared to non-using peers.

Schnakenberg Martin, Ashley M · 2020

Compared to non-using schizophrenia patients (n=36), those with lifetime cannabis use (n=35) expressed less ability to express emotions, were less likely to anticipate pleasure, and had poorer social functioning.

Cannabidiol as a treatment option for schizophrenia: recent evidence and current studies.

Schoevers, Julie · 2020

Recent trials focused on sub-acute schizophrenia, clinical high-risk for psychosis (CHR-P), and frequent cannabis users.

Paternal Δ9-Tetrahydrocannabinol Exposure Prior to Mating Elicits Deficits in Cholinergic Synaptic Function in the Offspring.

Slotkin, Theodore A · 2020

After 28 days of THC exposure (0, 2, or 4 mg/kg/day) in male rats, followed by mating with drug-naive females, offspring showed dose-dependent decreases in hemicholinium-3 binding (presynaptic acetylcholine activity) with regionally selective increases in choline acetyltransferase.

Cognitive function and adaptive skills after a one-year trial of cannabidiol (CBD) in a pediatric sample with treatment-resistant epilepsy.

Thompson, Matthew D · 2020

Among 38 pediatric patients (ages 3-19) with treatment-resistant epilepsy, those who completed cognitive testing showed no significant changes after one year of CBD.

Impaired cognitive performance under psychosocial stress in cannabis-dependent men is associated with attenuated precuneus activity.

Zhao, Weihua · 2020

During stress but not during a no-stress condition, cannabis users showed impaired performance on mental arithmetic compared to controls.

Cannabis cessation among youth: rates, patterns and academic outcomes in a large prospective cohort of Canadian high school students.

Zuckermann, Alexandra M · 2020

Only 14.8% decreased use between grades, with two-thirds making only incremental changes.

Adolescent exposure to Δ9-tetrahydrocannabinol delays acquisition of paired-associates learning in adulthood.

Abela, Andrew R · 2019

THC-exposed rats took longer to learn a paired-associates learning task in adulthood, particularly with visually identical stimuli.

Cannabidiol (CBD) content in vaporized cannabis does not prevent tetrahydrocannabinol (THC)-induced impairment of driving and cognition.

Arkell, Thomas R · 2019

Both THC-dominant and THC/CBD equivalent cannabis increased lane weaving during simulated driving.

Threat Responsiveness as a Function of Cannabis and Alcohol Use Disorder Severity.

Blair, Robert James R · 2019

Increasing CUD symptomatology was associated with decreased responding to looming threat stimuli in regions including rostral frontal cortex, fusiform gyrus, and amygdala.

Regular cannabis use is associated with altered activation of central executive and default mode networks even after prolonged abstinence in adolescent users: Results from a complementary meta-analysis.

Blest-Hopley, Grace · 2019

Adolescent cannabis users abstinent for over 25 days showed significantly greater activation in central executive and default mode network components compared to non-using controls.

Cerebellar alterations in cannabis users: A systematic review.

Blithikioti, Chrysanthi · 2019

The three most consistent findings across 40 studies were: (1) increased cerebellar gray matter volume after chronic use, (2) altered cerebellar resting state activity after acute or chronic use, and (3) deficits in memory, decision-making, and associative learning (cerebellar-dependent tasks).

The neuropsychological profiles of young psychosis patients with and without current cannabis use.

Bogaty, Sophia E R · 2019

Healthy controls outperformed both patient groups across most cognitive measures, but no significant differences were found between cannabis-using (n=24) and cannabis-abstinent (n=79) psychosis patients on any cognitive measure, including premorbid intelligence, processing speed, flexibility, memory, attention, and visuospatial function..

Acute effects of ∆9-tetrahydrocannabinol (THC) on resting state brain function and their modulation by COMT genotype.

Bossong, Matthijs G · 2019

THC increased perfusion in bilateral insula, medial superior frontal cortex, and left orbital frontal gyrus.

Cannabis effects on brain structure, function, and cognition: considerations for medical uses of cannabis and its derivatives.

Burggren, Alison C · 2019

Decades of research link recreational cannabis use to cognitive impairment across multiple domains, structural and functional brain differences associated with early and heavy use, and heightened risks during adolescence when brain development is ongoing.

Driving Under the Influence of Cannabis: A Framework for Future Policy.

Chow, Robert M · 2019

Marijuana use is associated with significant cognitive and psychomotor effects.

Positive and Negative Effects of Cannabis and Cannabinoids on Health.

Cohen, Koby · 2019

Repeated cannabis use is associated with respiratory and cardiovascular disorders, cognitive alterations, psychosis, schizophrenia, and mood disorders.

Modulatory effects of cannabinoids on brain neurotransmission.

Cohen, Koby · 2019

CB1 and CB2 receptors interact with six major neurotransmitter systems: dopamine, serotonin, noradrenaline, GABA, glutamate, and opioids.

Deficient Functioning of Frontostriatal Circuits During the Resolution of Cognitive Conflict in Cannabis-Using Youth.

Cyr, Marilyn · 2019

Cannabis-using youth (n=28) showed decreased conflict-related activation in ventromedial prefrontal cortex, striatum, pallidum, and thalamus compared to healthy controls (n=32) during a Simon task.

The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study

Di Forti, Marta · 2019

This multicentre study across 11 sites in Europe and Brazil compared 901 people experiencing first-episode psychosis with 1,237 population controls.

Adult attention-deficit/hyperactivity disorder, risky substance use and substance use disorders: a follow-up study among young men.

Estévez-Lamorte, Natalia · 2019

ADHD predicted persistent risky alcohol and nicotine use and was positively linked to alcohol use disorder but negatively linked to cannabis use disorder at follow-up.

Age-related differences in the impact of cannabis use on the brain and cognition: a systematic review.

Gorey, Claire · 2019

General executive functioning appears more impaired in adolescent frequent cannabis users compared to adult users.

Cannabis and the developing brain: What does the evidence say?

Jacobus, Joanna · 2019

Across two prospective studies (3 and 6 years), recency, frequency, and age of onset of cannabis use were the key variables predicting poorer neural health outcomes.

Cannabis induced increase in striatal glutamate associated with loss of functional corticostriatal connectivity.

Mason, Natasha L · 2019

THC increased striatal glutamate concentrations and reduced functional connectivity (FC) between the nucleus accumbens and cortical areas, indicating increased dopamine activity.

Synergistic effects of marijuana abuse and HIV infection on neural activation during a cognitive interference task.

Meade, Christina S · 2019

The MJ+/HIV+ group showed the greatest activation increase in the left fronto-insular cortex during cognitive interference, beyond what either marijuana or HIV produced alone.

Marijuana use among adolescents is associated with deleterious alterations in mature BDNF.

Miguez, Maria Jose · 2019

Pre-existing BDNF levels did not differ between groups, but marijuana use predicted subsequent BDNF alterations (p=0.001).

Single and combined effects of plant-derived and synthetic cannabinoids on cognition and cannabinoid-associated withdrawal signs in mice.

Myers, Alyssa M · 2019

THC caused significant motor and cognitive impairment in Barnes maze; adding CBD did not attenuate these effects.

Distinct effects of cocaine and cocaine + cannabis on neurocognitive functioning and abstinence: A six-month follow-up study.

Oliveira, Hercílio Pereira de · 2019

Both cocaine groups performed worse than controls on multiple cognitive measures.

Urinary tetrahydrocannabinol is associated with poorer working memory performance and alterations in associated brain activity.

Owens, Max M · 2019

A positive urine THC screen was associated with worse working memory and differential brain response during an N-back task.

Developing a phone-based measure of impairment after acute oral ∆9-tetrahydrocannabinol.

Pabon, Elisa · 2019

Across two double-blind studies with oral THC (7.5 and 15 mg), standard computer tasks detected impairment in cognitive speed, reaction time, and working memory.

Marijuana use and major depressive disorder are additively associated with reduced verbal learning and altered cortical thickness.

Radoman, Milena · 2019

MDD and marijuana use had additive effects on memory recall and cortical thickness in the middle temporal gyrus.

Highs and lows of cannabinoid-dopamine interactions: effects of genetic variability and pharmacological modulation of catechol-O-methyl transferase on the acute response to delta-9-tetrahydrocannabinol in humans.

Ranganathan, Mohini · 2019

Val/Val individuals showed the greatest THC-induced working memory and attention deficits.

Association of CNR1 genotypes with changes in neurocognitive performance after eighteen-month treatment in patients with first-episode psychosis.

Rojnic Kuzman, Martina · 2019

Carriers of the CNR1 rs7766029 CC genotype showed significantly greater improvement in verbal memory (Wechsler, Wechsler 30') and attention (Digit span F).

Neurocognition and Subjective Experience Following Acute Doses of the Synthetic Cannabinoid JWH-018: Responders Versus Nonresponders.

Theunissen, Eef L · 2019

JWH-018 increased heart rate and impaired critical tracking and memory performance overall.

Aerobic Fitness Level Moderates the Association Between Cannabis Use and Executive Functioning and Psychomotor Speed Following Abstinence in Adolescents and Young Adults.

Wade, Natasha E · 2019

Increased cannabis use was associated with poorer working memory and psychomotor speed after 3 weeks of abstinence.

Effects of Cannabis Use and Subclinical ADHD Symptomology on Attention Based Tasks in Adolescents and Young Adults.

Wallace, Alexander L · 2019

Cannabis users demonstrated significantly slower hit rate response on the Continuous Performance Test (CPT), an attention task.

Clinical Correlates of Cannabis Use Among Individuals With Attention Deficit Hyperactivity Disorder.

Brandt, Ariel · 2018

Using data from the National Epidemiologic Survey on Alcohol and Related Conditions, researchers examined cannabis use patterns among adults with and without ADHD.

Hippocampal Protein Kinase C Signaling Mediates the Short-Term Memory Impairment Induced by Delta9-Tetrahydrocannabinol.

Busquets-Garcia, Arnau · 2018

Using a novel object recognition test in mice, researchers dissected the molecular mechanisms behind THC's effects on memory and made a key discovery: short-term and long-term memory impairment from THC operate through entirely different molecular pathways. THC impaired short-term memory specifically through activation of protein kinase C (PKC) in the hippocampus.

Modulation of acute effects of delta-9-tetrahydrocannabinol on psychotomimetic effects, cognition and brain function by previous cannabis exposure.

Colizzi, Marco · 2018

Using the same 24-participant THC challenge design, this companion study focused on cognitive processing and psychotomimetic effects.

The effect of interactions between genetics and cannabis use on neurocognition. A review.

Cosker, E · 2018

Researchers systematically reviewed 13 studies examining how genetic variations influence the cognitive effects of cannabis use.

The Psychiatric Consequences of Cannabinoids.

De Aquino, Joao P · 2018

This overview examined the psychiatric effects of both plant-based and synthetic cannabinoids across different timeframes. Acutely, cannabinoids produce multiphasic, dose-dependent effects on anxiety, mood, and perception while impairing cognition and psychomotor function.

Cortical thickness, cortical surface area and subcortical volumes in schizophrenia and bipolar disorder patients with cannabis use.

Hartberg, Cecilie Bhandari · 2018

Researchers compared brain scans of patients with schizophrenia or bipolar disorder who had used cannabis (132 patients) against those who had not (182 patients) and 277 healthy controls. After controlling for confounders including tobacco and alcohol use, cannabis-using patients showed reduced cortical thickness in the caudal middle frontal gyrus compared to non-user patients and healthy controls. However, when patients with co-occurring alcohol and other illicit drug use were excluded, these findings were no longer significant.

Adolescent Brain Surface Area Pre- and Post-Cannabis and Alcohol Initiation.

Infante, M Alejandra · 2018

Researchers obtained brain scans from 69 adolescents at baseline (ages 12-14, before any substance use) and again at follow-up (ages 17-21). Participants were split into three groups: alcohol-only initiators, alcohol-plus-cannabis initiators, and minimal-use controls. All groups showed surface area decreases over time (consistent with normal brain maturation), but the pattern differed by substance use. A significant group-by-time interaction appeared in three regions: bilateral medial orbitofrontal cortices and right insula.

Chronic Δ9-THC in Rhesus Monkeys: Effects on Cognitive Performance and Dopamine D2/D3 Receptor Availability.

John, William S · 2018

Six adult male rhesus monkeys were tested on cognitive tasks using touchscreen tests (CANTAB) before and during 12 weeks of daily THC (1.0-2.0 mg/kg). Acute THC impaired cognitive performance in a task-specific manner and reduced food-motivated responding and body temperature. During chronic treatment, THC produced persistent residual impairment only to working memory, measured 22 hours after each dose.

The relation between gray matter volume and the use of alcohol, tobacco, cocaine and cannabis in male polysubstance users.

Kaag, A M · 2018

Researchers measured gray matter volume in 169 men across six groups ranging from non-users to heavy polysubstance users (alcohol, tobacco, cocaine, and cannabis). The number of substances used was negatively associated with volume in the dorsal and ventral medial prefrontal cortex (mPFC).

Fronto-striatal effective connectivity of working memory in adults with cannabis use disorder.

Ma, Liangsuo · 2018

Researchers compared brain connectivity between 23 adults with cannabis use disorder and 23 demographically matched controls during a working memory (N-back) task. Compared to controls, CUD participants showed reduced modulatory connectivity from the right dorsolateral prefrontal cortex (R-DLPFC) to the left caudate during working memory. However, CUD participants showed increased connectivity in three other prefrontal-striatal pathways: left DLPFC to left caudate, right DLPFC to right caudate, and right ventrolateral PFC to left caudate. The authors interpreted this as a compensatory pattern: the CUD brain may recruit additional prefrontal-striatal connections to maintain working memory performance when the primary pathway is impaired..

Is Cannabis Use Associated With the Worst Inpatient Outcomes in Attention Deficit Hyperactivity Disorder Adolescents?

Patel, Rikinkumar S · 2018

Researchers analyzed 11,232 ADHD adolescent hospital admissions from 2010-2014, of which 1.79% had comorbid cannabis use disorder. CUD prevalence was highest in ages 15-18 (73%) and in white adolescents (71%). ADHD adolescents with CUD had significantly worse hospitalization outcomes: - 1.8 times higher odds of hospitalization costs exceeding the median ($12,247) - 2.1 times higher odds of inpatient stays exceeding 5 days - Higher rates of transfer to acute care hospitals and skilled nursing facilities Paradoxically, CUD was associated with reduced utilization of treatments: - Psychotropic medication use reduced by 55% (aOR = 0.448) - Behavioral therapy use reduced by 59% (aOR = 0.412) CUD dramatically increased alcohol abuse risk: 17-fold higher odds (aOR = 17.141)..

Adolescent THC exposure in female rats leads to cognitive deficits through a mechanism involving chromatin modifications in the prefrontal cortex.

Prini, Pamela · 2018

Adolescent THC exposure increased levels of the histone modification H3K9me3 and the enzyme Suv39H1 in the prefrontal cortex, altering expression of genes tied to synaptic plasticity.

Impact of substance use disorder on gray matter volume in schizophrenia.

Quinn, Margaret · 2018

Using voxel-based morphometry, researchers found that schizophrenia patients had reduced gray matter in several brain regions regardless of substance use history.

Association of cannabis with cognitive functioning in adolescents and young adults: A systematic review and meta-analysis

Scott, J. Cobb · 2018

This was the first quantitative synthesis of the cannabis-cognition literature in adolescents and young adults.

Cannabinoid receptor-mediated disruption of sensory gating and neural oscillations: A translational study in rats and humans.

Skosnik, Patrick D · 2018

Both THC and THC+CBD disrupted P50 sensory gating in humans and reduced evoked theta and gamma oscillations.

Adolescent cannabis use and brain systems supporting adult working memory encoding, maintenance, and retrieval.

Tervo-Clemmens, Brenden · 2018

Earlier cannabis age of onset was associated with longer reaction times and reduced posterior parietal cortex activation during encoding, which mediated the age-of-onset effect.

Altered orbitofrontal activity and dorsal striatal connectivity during emotion processing in dependent marijuana users after 28 days of abstinence.

Zimmermann, Kaeli · 2018

After 28+ days of abstinence, dependent marijuana users showed increased medial orbitofrontal cortex (mOFC) activity during negative emotional stimuli, stronger mOFC-dorsal striatal and mOFC-amygdala coupling, and increased mOFC-dorsal striatal resting connectivity compared to controls.

Attenuated frontal and sensory inputs to the basal ganglia in cannabis users.

Blanco-Hinojo, Laura · 2017

Resting-state brain imaging in 28 chronic cannabis users and 29 controls revealed two key connectivity changes.

The effects of synthetic cannabinoids on executive function.

Cohen, K · 2017

Across two study sites (Hungary and Israel), 38 synthetic cannabinoid users were compared with 43 recreational cannabis users and 41 non-users on computerized cognitive tests. Synthetic cannabinoid users performed significantly worse than both other groups on the n-back task (working memory accuracy), the Stroop task (response speed and accuracy, measuring inhibition), and a free-recall memory task (long-term memory).

Cannabis: An Overview of its Adverse Acute and Chronic Effects and its Implications.

Ford, Talitha C · 2017

The review surveyed evidence across multiple domains of cannabis harm.

Cannabis and Canada's children and youth.

Grant, Christina N · 2017

Cannabis is the most common illicit drug used by Canadian teenagers.

Smoking status and its relationship to demographic and clinical characteristics in first episode psychosis.

Grossman, Michael · 2017

In 140 patients entering specialized first-episode psychosis treatment, 53% smoked cigarettes: 47 were light/moderate smokers (1-19/day) and 27 were heavy smokers (20+/day).

Longitudinal study of hippocampal volumes in heavy cannabis users.

Koenders, L · 2017

This longitudinal study tracked hippocampal volumes in 20 heavy cannabis users and 23 matched controls over approximately 39 months using manual brain tracing, considered the gold standard for hippocampal measurement. At baseline, there were no differences in hippocampal volume between heavy users and non-users.

Nucleus accumbens functional connectivity at age 20 is associated with trajectory of adolescent cannabis use and predicts psychosocial functioning in young adulthood.

Lichenstein, Sarah D · 2017

Following 158 young men from a longitudinal study that began in infancy, researchers identified three distinct trajectories of cannabis use from ages 14 to 19: stable high use, escalating use, and stable low use. The trajectory of cannabis use significantly affected functional connectivity between the nucleus accumbens (the brain's reward center) and the medial prefrontal cortex.

Heavy cannabis use prior psychosis in schizophrenia: clinical, cognitive and neurological evidences for a new endophenotype?

Mallet, Jasmina · 2017

This study compared 34 schizophrenia patients who reported heavy cannabis use before their first psychotic episode with 27 patients who did not. The results were counterintuitive: heavy pre-psychosis cannabis users showed significantly fewer neurological soft signs (subtle neurological abnormalities considered markers of early neurodevelopmental impairment) and better cognitive functioning across multiple domains including reaction time, episodic memory, and visuoconstructive abilities. These findings held after controlling for alcohol and tobacco use.

Adverse Structural and Functional Effects of Marijuana on the Brain: Evidence Reviewed.

Mandelbaum, David E · 2017

This critical review focused specifically on evidence for structural and functional brain damage from cannabis, combined with neuropathological findings from a fatal case of cannabis-induced psychosis. The literature review found strong evidence that chronic cannabis abuse causes cognitive impairment and brain damage, particularly to white matter (the brain's communication cables), where CB1 cannabinoid receptors are abundant. The fatal case provided direct neuropathological evidence of white matter damage in a person who died from cannabis-induced psychosis, complementing the imaging-based evidence from living subjects. Regarding therapeutic claims, the review concluded that contrary to popular perception, there are few objective data supporting preferential use of cannabis over conventional therapy for neurological conditions such as multiple sclerosis, epilepsy, or schizophrenia.

Cannabis and alcohol use, and the developing brain.

Meruelo, A D · 2017

This review examined how cannabis and alcohol affect the adolescent brain during a period when white and grey matter are still maturing and sex hormones are driving structural changes. Neuroimaging studies revealed differences in brain development between substance-using and non-using adolescents, including altered white matter myelination and grey matter volumes.

Evaluation of divided attention psychophysical task performance and effects on pupil sizes following smoked, vaporized and oral cannabis administration.

Newmeyer, Matthew N · 2017

This controlled study compared impairment from smoked, vaporized, and oral cannabis on standard roadside sobriety tests used in driving under the influence evaluations. For inhaled cannabis (smoked and vaporized), no significant impairment was detected because testing occurred 1.5 and 3.5 hours after dosing, by which time peak effects had subsided. Oral cannabis (edibles) told a different story.

Recreational stimulants, herbal, and spice cannabis: The core psychobiological processes that underlie their damaging effects.

Parrott, Andrew C · 2017

The review proposes that all recreational psychoactive drugs, including cannabis, cause harm through a shared core mechanism: acute mood gains followed by mood deficits on withdrawal, creating a cycle of psychobiological fluctuations. These mood swings are surface indicators of deeper disruptions.

Opposing Effects of Cannabis Use on Late Auditory Repetition Suppression in Schizophrenia Patients and Healthy Control Subjects.

Rentzsch, Johannes · 2017

Researchers measured how the brain filters repeated auditory signals in four groups: schizophrenia patients with and without cannabis use, and healthy controls with and without cannabis use.

A review of Indian research on co-occurring cannabis use disorders& psychiatric disorders.

Singh, Shalini · 2017

The review identified 52 published Indian studies on co-occurring cannabis use disorders and psychiatric conditions.

Weeding Out the Truth: Adolescents and Cannabis.

Ammerman, Seth · 2016

This review addressed the growing tension between expanding cannabis legalization and concerns about adolescent use.

Cannabis and neuropsychiatry, 1: benefits and risks.

Andrade, Chittaranjan · 2016

This review summarized the evidence on both benefits and risks of cannabis and cannabinoids.

Cannabis and its effects on driving skills.

Bondallaz, Percy · 2016

This review synthesized evidence from laboratory, simulator, on-road, and brain imaging studies to assess how cannabis affects driving performance. Cannabis impaired actual driving by increasing lane weaving and the mean distance to the vehicle ahead.

Effects of Marijuana Use on Brain Structure and Function: Neuroimaging Findings from a Neurodevelopmental Perspective.

Brumback, T · 2016

This review examined neuroimaging evidence on how marijuana affects brain structure and function, with a focus on developmental timing. A wide range of research has documented neurocognitive deficits associated with marijuana use, particularly when use begins during childhood or adolescence.

Effects of drugs of abuse on hippocampal plasticity and hippocampus-dependent learning and memory: contributions to development and maintenance of addiction.

Kutlu, Munir Gunes · 2016

This review examined how drugs of abuse, including cannabis, interact with the hippocampus, a brain region critical for learning and memory, to contribute to addiction. The relationship between cannabis and hippocampal function follows a two-phase pattern.

Acute and chronic effects of cannabinoids on effort-related decision-making and reward learning: an evaluation of the cannabis 'amotivational' hypotheses.

Lawn, Will · 2016

The "amotivational syndrome" associated with cannabis is one of the most debated topics in cannabis research.

The impact of ADHD persistence, recent cannabis use, and age of regular cannabis use onset on subcortical volume and cortical thickness in young adults.

Lisdahl, Krista M · 2016

Researchers compared brain structure in young adults with and without childhood ADHD who did or did not use cannabis regularly.

Adolescent Cannabis Use: What is the Evidence for Functional Brain Alteration?

Lorenzetti, Valentina · 2016

Adolescence is a critical period for brain development, particularly in regions with high cannabinoid receptor density.

Are adolescents more vulnerable to the harmful effects of cannabis than adults? A placebo-controlled study in human males.

Mokrysz, C · 2016

This groundbreaking study was the first to directly compare cannabis effects in adolescent (16-17) and adult (24-28) male users under controlled conditions. The results defied simple assumptions about adolescent vulnerability.

Go/No Go task performance predicts cortical thickness in the caudal inferior frontal gyrus in young adults with and without ADHD.

Newman, Erik · 2016

Researchers examined the inferior frontal gyrus, a brain region central to stopping yourself from acting impulsively.

Mixed-amphetamine salts increase abstinence from marijuana in patients with co-occurring attention-deficit/hyperactivity disorder and cocaine dependence.

Notzon, Daniel P · 2016

In a secondary analysis of a 14-week randomized controlled trial, researchers found that people with co-occurring ADHD and cocaine dependence who received mixed amphetamine salts (MAS-XR) had a significant decrease in the proportion of weeks where they used any marijuana, compared to placebo. However, among the weeks when participants did use marijuana, the proportion of days they used did not change.

Cannabis and cocaine decrease cognitive impulse control and functional corticostriatal connectivity in drug users with low activity DBH genotypes.

Ramaekers, J G · 2016

Researchers gave 122 regular drug users acute doses of cannabis, cocaine, and placebo and measured cognitive impulsivity and brain connectivity.

ADHD and cannabis use in young adults examined using fMRI of a Go/NoGo task.

Rasmussen, Jerod · 2016

Researchers compared brain function during an impulse control task (Go/NoGo) across four groups: ADHD with and without cannabis use, and controls with and without cannabis use. Participants with ADHD made significantly more errors on the task and showed less activation in frontal and parietal brain regions and frontal-striatal circuits, regardless of whether they used cannabis.

Attentional dysfunction in abstinent long-term cannabis users with and without schizophrenia.

Rentzsch, Johannes · 2016

Researchers measured attention-related brainwave responses (P300) in four groups: schizophrenia patients with and without chronic cannabis use, and healthy controls with and without chronic cannabis use.

Should we care about sativex-induced neurobehavioral effects? A 6-month follow-up study.

Russo, M · 2016

Forty cannabis-naive multiple sclerosis patients were assessed with comprehensive neuropsychological testing before starting Sativex treatment and again at 1 and 6 months.

Prenatal marijuana exposure impacts executive functioning into young adulthood: An fMRI study.

Smith, Andra M · 2016

Thirty-one young adults (ages 18-22) from the Ottawa Prenatal Prospective Study, a long-running longitudinal study, underwent fMRI during four executive function tasks: visuospatial working memory, response inhibition, verbal working memory, and interference control. Sixteen had been prenatally exposed to marijuana while 15 had not.

Cannabinoid modulation of memory consolidation within the cerebellum.

Steinmetz, Adam B · 2016

Researchers injected cannabinoid compounds directly into the cerebellar cortex of rats at different time points relative to eyeblink conditioning, a form of motor learning that depends on the cerebellum. When given before training sessions, the cannabinoid agonist WIN55,212-2 and drugs that increase or decrease endocannabinoid levels all impaired learning.

Abnormal medial prefrontal cortex activity in heavy cannabis users during conscious emotional evaluation.

Wesley, Michael J · 2016

Researchers used fMRI to compare brain activity between 16 heavy cannabis users and 17 non-using controls as they evaluated emotional images from a standardized set (IAPS). Both groups identified the same images as emotional and showed similar activation in visual, midbrain, and middle cingulate regions.

Not in Education, Employment, or Training status among young Swiss men. Longitudinal associations with mental health and substance use.

Baggio, Stéphanie · 2015

This study tracked 4,758 young Swiss men in their early 20s to understand what leads to becoming "NEET" (Not in Education, Employment, or Training).

The role of endocannabinoid signaling in the molecular mechanisms of neurodegeneration in Alzheimer's disease.

Bedse, Gaurav · 2015

This review examined the role of endocannabinoid signaling in Alzheimer's disease (AD) pathology.

Impairment of inhibitory control processing related to acute psychotomimetic effects of cannabis.

Bhattacharyya, Sagnik · 2015

Researchers gave 36 healthy men with minimal cannabis exposure either 10mg of oral THC or placebo in a double-blind crossover design, then scanned their brains during a task requiring them to withhold automatic responses (Go/No-Go task). THC increased inhibition errors and reduced inhibition efficiency compared to placebo.

Dissecting the cannabinergic control of behavior: The where matters.

Busquets-Garcia, Arnau · 2015

This review examined how the location of CB1 receptors across different brain cell types and subcellular compartments determines the specific behavioral effects of cannabinoids.

Smoked cannabis' psychomotor and neurocognitive effects in occasional and frequent smokers.

Desrosiers, Nathalie A · 2015

Fourteen frequent cannabis smokers (4+ times per week) and 11 occasional smokers (less than twice per week) smoked a single 6.8% THC cigarette in a controlled setting.

The influence of cannabinoids on learning and memory processes of the dorsal striatum.

Goodman, Jarid · 2015

This review examined how cannabinoids affect the dorsal striatum, a brain region that controls habit formation and stimulus-response (S-R) learning.

Medical marijuana: review of the science and implications for developmental-behavioral pediatric practice.

Hadland, Scott E · 2015

This review for developmental-behavioral pediatricians examined three domains: cannabis use epidemiology among youth, neurocognitive effects in adolescents, and proposed medical uses in pediatric conditions. Regular cannabis use among adolescents was associated with well-recognized neurocognitive changes, with the developing brain being particularly susceptible due to the endocannabinoid system's role in normal neurodevelopment.

Brain activation to negative stimuli mediates a relationship between adolescent marijuana use and later emotional functioning.

Heitzeg, Mary M · 2015

Researchers tracked 40 participants from the Michigan Longitudinal Study, comparing 20 heavy marijuana users with 20 minimal-use controls.

Non-smoker exposure to secondhand cannabis smoke II: Effect of room ventilation on the physiological, subjective, and behavioral/cognitive effects.

Herrmann, Evan S · 2015

Non-cannabis-using individuals were exposed to secondhand smoke from six people smoking 11.3% THC cannabis in a sealed chamber for one hour under two conditions: unventilated and ventilated (11 air exchanges per hour). Unventilated exposure produced detectable THC in blood and urine, minor heart rate increases, mild-to-moderate self-reported sedation, and impaired performance on a cognitive task (digit symbol substitution).

Acute effects of delta-9-tetrahydrocannabinol, cannabidiol and their combination on facial emotion recognition: a randomised, double-blind, placebo-controlled study in cannabis users.

Hindocha, Chandni · 2015

Forty-eight cannabis users received THC (8mg), CBD (16mg), THC+CBD (8mg+16mg), and placebo by inhalation in a four-way crossover design.

Influences of behavior and academic problems at school entry on marijuana use transitions during adolescence in an African-American sample.

Reboussin, Beth A · 2015

Researchers tracked 458 low-income, urban African American children from first grade through early high school to see how early academic and behavior problems related to later marijuana use. Two behavior problem classes emerged at school entry: externalizing (acting out) and attention/concentration difficulties.

Multiple sclerosis, cannabis, and cognition: A structural MRI study.

Romero, Kristoffer · 2015

Researchers compared 20 MS patients who smoked cannabis for symptom relief with 19 matched MS patients who did not.

Response inhibition and elevated parietal-cerebellar correlations in chronic adolescent cannabis users.

Behan, B · 2014

Adolescent heavy cannabis users and matched non-using controls completed a Go/No-Go task (requiring them to inhibit a habitual response) during brain imaging.

Childhood and current ADHD symptom dimensions are associated with more severe cannabis outcomes in college students.

Bidwell, L C · 2014

In a study of 376 college undergraduates, researchers examined how specific ADHD symptom dimensions related to cannabis outcomes.

Acute and non-acute effects of cannabis on human memory function: a critical review of neuroimaging studies.

Bossong, Matthijs G · 2014

This review synthesized neuroimaging studies examining both acute THC effects and long-term effects of cannabis use on learning and memory in adults and adolescents.

Resting state functional magnetic resonance imaging reveals distinct brain activity in heavy cannabis users - a multi-voxel pattern analysis.

Cheng, H · 2014

Researchers used an advanced multi-voxel pattern analysis technique to identify brain differences in heavy male cannabis users compared to controls during resting-state fMRI (no task being performed).

ADHD symptoms, autistic traits, and substance use and misuse in adult Australian twins.

De Alwis, Duneesha · 2014

In a study of 3,080 young adult Australian twins, researchers examined how ADHD symptoms and autistic traits independently related to substance use.

Executive attention impairment in adolescents with schizophrenia who have used cannabis.

Epstein, Katherine A · 2014

Researchers compared attention performance across four groups of adolescents: early-onset schizophrenia with cannabis use disorder (EOS+CUD, n=18), schizophrenia only (EOS, n=34), cannabis use disorder only (CUD, n=29), and healthy controls (n=53).

Cannabis abstinence during treatment and one-year follow-up: relationship to neural activity in men.

Kober, Hedy · 2014

Twenty cannabis-dependent men completed an fMRI cognitive control task before starting a 12-week treatment trial.

Subtypes of attention deficit-hyperactivity disorder (ADHD) and cannabis use

Loflin, Mallory · 2014

Among daily cannabis users, a higher proportion met symptom criteria for ADHD subtypes that include hyperactive‑impulsive symptoms compared with the inattentive subtype.

Effects of cannabis on cognition in patients with MS: a psychometric and MRI study.

Pavisian, Bennis · 2014

Compared to matched MS patients who did not use cannabis, cannabis-using MS patients performed significantly worse on two cognitive measures: the more demanding version of the Paced Auditory Serial Addition Test (processing speed) and the 10/36 Spatial Recall Test (visual memory). On fMRI during a working memory task, cannabis users showed more diffuse cerebral activation across all difficulty levels and made more errors on the most demanding task.

Functional connectivity alterations in brain networks relevant to self-awareness in chronic cannabis users.

Pujol, Jesus · 2014

Compared to 29 controls, 28 heavy cannabis users showed increased functional connectivity within the core of the Default Mode Network and Insula Network, and enhanced anticorrelation between these two networks.

THC:CBD spray and MS spasticity symptoms: data from latest studies.

Rekand, Tiina · 2014

A randomized, placebo-controlled long-term trial demonstrated that THC:CBD spray (Sativex) was not associated with cognitive decline, depression, or significant mood changes after 12 months of treatment.

Repeated Δ9-tetrahydrocannabinol exposure in adolescent monkeys: persistent effects selective for spatial working memory.

Verrico, Christopher D · 2014

Seven pairs of adolescent male rhesus monkeys, matched for baseline cognitive ability, received either THC or vehicle intravenously 5 days/week for 6 months.

Dispelling the myth of "smart drugs": cannabis and alcohol use problems predict nonmedical use of prescription stimulants for studying.

Arria, Amelia M · 2013

Researchers followed 984 college students over four annual waves.

Weed or wheel! FMRI, behavioural, and toxicological investigations of how cannabis smoking affects skills necessary for driving.

Battistella, Giovanni · 2013

Thirty-one male occasional cannabis smokers underwent fMRI while performing a visuo-motor tracking task after smoking cannabis or placebo.

Δ9-THC-caused synaptic and memory impairments are mediated through COX-2 signaling.

Chen, Rongqing · 2013

Published in the journal Cell, this study identified COX-2 (cyclooxygenase-2) as the key mediator of THC's memory-impairing effects.

Cannabis use and cannabis use disorders among individuals with mental illness

Lev-Ran, Shaul · 2013

People reporting a 12-month mental illness had much higher rates of cannabis involvement than those without.

Impact of ADHD and cannabis use on executive functioning in young adults.

Tamm, Leanne · 2013

Researchers compared cognitive performance in young adults (average age 24) across four groups: those with childhood ADHD who used cannabis, those with ADHD who did not, non-ADHD cannabis users, and non-ADHD non-users.

Effects of cannabis use on event related potentials in subjects at ultra high risk for psychosis and healthy controls.

van Tricht, Mirjam J · 2013

Researchers measured brain wave responses (event-related potentials, or ERPs) in 48 ultra-high-risk (UHR) subjects and 50 healthy controls, split into cannabis users and non-users within each group.

Single doses of THC and cocaine decrease proficiency of impulse control in heavy cannabis users.

van Wel, J H P · 2013

In a study of 61 heavy cannabis users with cocaine use history, single doses of THC impaired both psychomotor function and impulse control accuracy.

Approach-bias predicts development of cannabis problem severity in heavy cannabis users: results from a prospective FMRI study.

Cousijn, Janna · 2012

Thirty-three heavy cannabis users and 36 controls completed an fMRI task measuring automatic approach and avoidance tendencies toward cannabis-related images.

Acute cannabinoids impair working memory through astroglial CB1 receptor modulation of hippocampal LTD.

Han, Jing · 2012

This study overturned a fundamental assumption about how cannabis impairs memory.

Functional connectivity in brain networks underlying cognitive control in chronic cannabis users.

Harding, Ian H · 2012

Twenty-one current cannabis users with over 10 years of near-daily use were compared to 21 matched controls during a cognitive control task (Multi-Source Interference Task).

Altered cerebral blood flow and neurocognitive correlates in adolescent cannabis users.

Jacobus, Joanna · 2012

Twenty-three heavy adolescent marijuana users (200+ lifetime use days) and 23 matched controls underwent brain perfusion scans at baseline and after 4 weeks of monitored abstinence (confirmed by urine testing).

The effect of cannabis use and cognitive reserve on age at onset and psychosis outcomes in first-episode schizophrenia.

Leeson, Verity C · 2012

Ninety-nine first-episode schizophrenia patients were divided into lifetime cannabis users and never-users.

Cannabinoids disrupt hippocampal sharp wave-ripples via inhibition of glutamate release.

Maier, Nikolaus · 2012

Using both in vivo and in vitro recordings in mice, researchers demonstrated that activating CB1 receptors suppressed sharp wave-ripples (SWRs) in the hippocampus.

Persistent cannabis users show neuropsychological decline from childhood to midlife

Meier, Madeline H. · 2012

People who used cannabis persistently across early adulthood showed declines across multiple neuropsychological domains by age 38 compared to their own pre-use performance at age 13.

Endocannabinoids in nervous system health and disease: the big picture in a nutshell.

Skaper, Stephen D · 2012

The review provided a broad overview of the endocannabinoid system (ECS), describing how its two main signaling molecules, anandamide and 2-AG, regulate brain function through cannabinoid receptors.

Expecting innovation: psychoactive drug primes and the generation of creative solutions.

Hicks, Joshua A · 2011

Researchers tested whether substance-related cues (images, words) could enhance creative performance through the power of expectation alone, without any actual drug consumption. In Study 1, participants were briefly exposed to either marijuana-related or neutral stimuli.

Effects of cannabis on cognitive function in patients with multiple sclerosis.

Honarmand, Kimia · 2011

Researchers compared 25 MS patients who used cannabis to 25 matched MS non-users using a comprehensive neuropsychological battery designed specifically for MS. Cannabis users performed significantly worse on information processing speed, working memory, executive functions, and visuospatial perception.

Evidence for involvement of the insula in the psychotropic effects of THC in humans: a double-blind, randomized pharmacological MRI study.

van Hell, Hendrika H · 2011

Twenty-three subjects underwent pharmacological MRI after receiving THC or placebo.

Modulation of auditory and visual processing by delta-9-tetrahydrocannabinol and cannabidiol: an FMRI study.

Winton-Brown, Toby T · 2011

Fourteen healthy volunteers were scanned with fMRI on three occasions after receiving THC (10 mg), CBD (600 mg), or placebo.

Chronic use of cannabis and poor neural efficiency in verbal memory ability.

Battisti, Robert A · 2010

Twenty-four chronic cannabis users (mean 17 years of near-daily use) and 24 non-using controls were tested on a verbal memory task while brain electrical activity (ERPs) was recorded. Cannabis users showed poorer recall.

Chronic cannabis users show altered neurophysiological functioning on Stroop task conflict resolution.

Battisti, Robert A · 2010

Twenty-one chronic cannabis users (mean 16.4 years near-daily use, unintoxicated) and 19 controls completed a Stroop color-naming task while ERPs were recorded. Cannabis users made significantly more errors specifically on incongruent trials (where the word meaning conflicts with the ink color, like "RED" written in blue).

Opposite effects of delta-9-tetrahydrocannabinol and cannabidiol on human brain function and psychopathology.

Bhattacharyya, Sagnik · 2010

In a two-part study, 15 healthy men completed four tasks during fMRI after receiving THC (10 mg), CBD (600 mg), or placebo. THC and CBD had opposite effects on brain activation across all four tasks: - In the striatum during verbal recall - In the hippocampus during response inhibition - In the amygdala while viewing fearful faces - In the superior temporal cortex during speech processing - In the occipital cortex during visual processing In a second experiment with 6 volunteers, CBD pretreatment prevented the acute psychotic symptoms normally induced by intravenous THC. This demonstrated that the two main cannabis compounds have fundamentally opposing brain effects, and that CBD can actively block THC-induced psychosis..

The effects of cannabis and alcohol on simulated arterial driving: Influences of driving experience and task demand.

Lenné, Michael G · 2010

Twenty-five experienced and 22 inexperienced drivers completed nine simulated driving conditions combining three cannabis doses (placebo, low, high) with three alcohol doses (placebo, low, high). High cannabis doses caused decreased mean speed, increased speed and lateral position variability, increased headways, and longer reaction times.

Neuroimaging in cannabis use: a systematic review of the literature.

Martín-Santos, R · 2010

Researchers systematically reviewed 66 brain imaging studies, of which 41 met inclusion criteria.

Cannabis use and cognitive functioning in first-episode schizophrenia patients.

Rodríguez-Sánchez, José Manuel · 2010

Researchers compared cognitive functioning between cannabis-using and non-using patients with first-episode schizophrenia.

Psychopathological and cognitive effects of therapeutic cannabinoids in multiple sclerosis: a double-blind, placebo controlled, crossover study.

Aragona, Massimiliano · 2009

Seventeen cannabis-naive MS patients were randomized in a double-blind crossover trial to receive Sativex or placebo for 3-week periods, with comprehensive psychological and cognitive assessments. No significant differences were found between the Sativex and placebo phases on any measured psychological or cognitive variable.

Cannabis and anxiety: a critical review of the evidence

Crippa, Jose Alexandre S. · 2009

Acute anxiety reactions and panic attacks were commonly reported during cannabis intoxication.

Cognitive and psychomotor effects in males after smoking a combination of tobacco and cannabis containing up to 69 mg delta-9-tetrahydrocannabinol (THC).

Hunault, Claudine C · 2009

Twenty-four non-daily male cannabis users smoked cannabis cigarettes containing 0, 29.3, 49.1, or 69.4 mg THC in a four-way crossover design. Response time slowed linearly across all cognitive tasks (simple reaction time, visual-spatial attention, sustained attention, divided attention, and short-term memory) as THC dose increased.

Reduced memory and attention performance in a population-based sample of young adults with a moderate lifetime use of cannabis, ecstasy and alcohol.

Indlekofer, F · 2009

Researchers tested 284 young adults (ages 22-34) drawn from a large epidemiological study, avoiding the recruitment biases common in drug research. Ecstasy and cannabis use were both significantly related to poorer episodic memory function in a dose-related manner, meaning more use was associated with more impairment. Attentional measures showed small but significant effects.

Cannabis abuse and addiction: a contemporary literature review.

Iyalomhe, G B S · 2009

This review synthesized recent developments in understanding cannabis abuse and addiction, with particular focus on neurobiological mechanisms. Recent advances identified dopamine and serotonin (5-HT) as key neuronal substrates responsible for the rewarding effects of cannabis and the addictive process.

Cannabinoid modulation of hippocampal long-term memory is mediated by mTOR signaling.

Puighermanal, Emma · 2009

Researchers discovered that THC activates the mTOR/p70S6K pathway in the mouse hippocampus, a signaling cascade that controls new protein synthesis. This activation correlated with THC-induced memory impairment.

Neurocognitive performance during acute THC intoxication in heavy and occasional cannabis users.

Ramaekers, J G · 2009

Twelve occasional cannabis users and 12 heavy users smoked THC (500 mcg/kg) or placebo in a double-blind crossover design, with performance tested at intervals over 8 hours. Occasional users showed significant impairment on perceptual motor control (critical tracking), divided attention processing, and motor inhibition (stop signal task) after THC. Heavy users showed no impairment on any task except the stop signal task, where only stop reaction time increased, and only at high blood THC concentrations. Importantly, baseline (sober) performance comparisons between heavy and occasional users showed no persistent performance differences, arguing against residual THC impairment in heavy users. These results demonstrated that cannabis use history strongly determines the behavioral response to a given THC dose..

The effect of cannabis compared with alcohol on driving.

Sewell, R Andrew · 2009

This review compared the driving-related effects of cannabis and alcohol. Both substances impaired driving skills in a dose-related fashion, but the patterns were fundamentally different.

Neural basis of Delta-9-tetrahydrocannabinol and cannabidiol: effects during response inhibition.

Borgwardt, Stefan J · 2008

Fifteen healthy volunteers performed a Go/No-Go task (requiring them to withhold a response on certain trials) under three conditions: THC, CBD, or placebo, in a double-blind crossover design with fMRI. THC attenuated activation in the right inferior frontal gyrus and anterior cingulate cortex, two brain regions well established as critical for response inhibition (the ability to stop an action once initiated). CBD produced a different pattern entirely: it deactivated the left temporal cortex and insula, regions not typically associated with response inhibition. Importantly, these brain changes were not explained by differences in anxiety, intoxication, sedation, or psychotic-like symptoms between conditions, suggesting direct pharmacological effects on brain function rather than secondary consequences of feeling impaired..

Auditory event-related potentials (P3) and cognitive performance in recreational ecstasy polydrug users: evidence from a 12-month longitudinal study.

de Sola, Susana · 2008

Researchers followed three groups for one year: 14 ecstasy polydrug users, 13 cannabis-only users, and 22 drug-free controls, measuring cognitive performance and brain event-related potentials (P300/P3). After one year, ecstasy users showed significant cognitive deficits compared to controls in word fluency, processing speed, and memory recognition.

Deficits in learning and memory: parahippocampal hyperactivity and frontocortical hypoactivity in cannabis users.

Nestor, Liam · 2008

Two experiments examined learning and memory in cannabis users.

Effects of acute oral Delta9-tetrahydrocannabinol and standardized cannabis extract on the auditory P300 event-related potential in healthy volunteers.

Roser, Patrik · 2008

In a double-blind crossover study, 20 healthy volunteers received pure THC, a standardized cannabis extract containing THC and CBD, or placebo on separate occasions. As expected, pure THC significantly reduced P300 amplitude at frontal, central, and parietal electrodes.

Acute and chronic cannabinoid treatment differentially affects recognition memory and social behavior in pubertal and adult rats.

Schneider, Miriam · 2008

Researchers gave pubertal rats (postnatal day 40-65) and adult rats (postnatal day 80+) daily injections of the synthetic cannabinoid WIN 55,212-2 for 25 days and tested behavior at three time points: immediately after the first dose, 24 hours after stopping, and 15 days after stopping. Pubertal-treated rats showed persistent deficits in both object and social recognition memory, indicating impaired short-term information processing.

Functional imaging studies in cannabis users.

Chang, Linda · 2007

This review examined the existing neuroimaging literature on cannabis users, covering both acute THC administration studies and chronic use studies. Acute THC studies (mostly using PET) consistently found that THC increases brain activation in frontal, paralimbic, and cerebellar regions, matching the drug's known behavioral effects. For chronic users, the picture was different.

Effects of frequent cannabis use on hippocampal activity during an associative memory task.

Jager, Gerry · 2007

Twenty frequent cannabis users and 20 matched non-users underwent functional MRI while performing an associative memory task (learning to link pairs of items together). Cannabis users showed significantly lower activation in the parahippocampal regions and right dorsolateral prefrontal cortex compared to non-users.

Acute effects of Delta9-tetrahydrocannabinol and standardized cannabis extract on the auditory evoked mismatch negativity.

Juckel, Georg · 2007

In a double-blind, placebo-controlled crossover study, 22 healthy volunteers received either pure THC, a standardized cannabis extract containing both THC and CBD, or placebo on separate occasions. The cannabis extract (THC + CBD) produced significantly greater mismatch negativity (MMN) amplitudes at central brain electrodes compared to both placebo and pure THC.

Changes in cannabis use and its consequences over 3 years in a remote indigenous population in northern Australia.

Clough, Alan R · 2006

Researchers conducted a 3-year follow-up in remote Aboriginal communities in Arnhem Land, Northern Territory, Australia.

Brain neuroimaging in cannabis use: a review.

Quickfall, Jeremy · 2006

This systematic review examined both structural and functional neuroimaging studies of cannabis use.

Effects of prenatal marijuana on visuospatial working memory: an fMRI study in young adults.

Smith, Andra M · 2006

Researchers scanned 31 participants from the Ottawa Prenatal Prospective Study (16 prenatally exposed to cannabis, 15 non-exposed) at age 18-22 using fMRI during a visuospatial working memory task.

Nicotine and cannabinoids: parallels, contrasts and interactions.

Viveros, Maria-Paz · 2006

This review examined the pharmacological interactions between nicotine and cannabis, two drugs increasingly used in combination, especially by adolescents and young adults. Animal studies suggested that the reinforcing effects of both drugs may be enhanced by joint consumption.

Cannabis use, cognitive performance and mood in a sample of workers.

Wadsworth, E J K · 2006

Cannabis users and controls completed laboratory cognitive tests before and after work at the start and end of a working week, along with daily workplace performance diaries. Cannabis use was associated with lower alertness and slower response organization across testing sessions.

Neurophysiological and subjective profile of marijuana with varying concentrations of cannabinoids.

Ilan, A B · 2005

Twenty-three healthy marijuana users (12 men, 11 women) participated in four sessions where they smoked marijuana cigarettes under blinded conditions.

Cognitive consequences of cannabis use: comparison with abuse of stimulants and heroin with regard to attention, memory and executive functions.

Lundqvist, Thomas · 2005

This review compared cognitive consequences across different drug classes using neuroimaging and neuropsychological evidence. Cannabis acutely causes loss of internal control and cognitive impairment, particularly in attention and memory.

Self-reported psychopathological symptoms in recreational ecstasy (MDMA) users are mainly associated with regular cannabis use: further evidence from a combined cross-sectional/longitudinal investigation.

Daumann, Jörg · 2004

At baseline, ecstasy users reported significantly more psychological complaints than controls.

Spatial working memory in heavy cannabis users: a functional magnetic resonance imaging study.

Kanayama, Gen · 2004

Using functional MRI, 12 heavy cannabis users (6-36 hours after last use) showed increased activation in brain regions typically used for spatial working memory (prefrontal cortex, anterior cingulate) compared to 10 controls.

Effects of prenatal marijuana on response inhibition: an fMRI study of young adults.

Smith, Andra M · 2004

Using fMRI, 31 young adults from the Ottawa Prenatal Prospective Study showed that greater prenatal marijuana exposure was associated with increased neural activity in bilateral prefrontal cortex and right premotor cortex during response inhibition tasks.

Cannabinoids on the brain.

Irving, Andrew J · 2002

The review synthesized research on how cannabinoids interact with the brain across multiple systems.

Endocannabinoids in cognition and dependence.

Lichtman, A H · 2002

The review synthesized evidence from two approaches: pharmacological blockade of CB1 receptors using SR141716A, and genetic knockout mice lacking the CB1 receptor.

Treatment of Tourette's syndrome with Delta 9-tetrahydrocannabinol (THC): a randomized crossover trial.

Müller-Vahl, K R · 2002

THC significantly reduced tics (p=0.015) and obsessive-compulsive behavior (p=0.041) compared to placebo.

Influence of treatment of Tourette syndrome with delta9-tetrahydrocannabinol (delta9-THC) on neuropsychological performance.

Müller-Vahl, K R · 2001

In 12 adult Tourette syndrome patients given a single dose of 5-10 mg THC or placebo, researchers found no significant differences in verbal memory, visual memory, reaction time, intelligence, sustained attention, divided attention, vigilance, or mood.

Impaired cognitive performance in drug free users of recreational ecstasy (MDMA).

Gouzoulis-Mayfrank, E · 2000

Researchers compared cognitive performance across three carefully matched groups of 28 participants each: ecstasy users (who also used cannabis), cannabis-only users, and non-users.

The effects of cannabinoids on the brain.

Ameri, A · 1999

This extensive review covered the full spectrum of cannabis effects on the brain, from molecular mechanisms to behavioral consequences. A striking finding was that recent research had revealed THC-induced cell death in the hippocampus, with neuron shrinkage and DNA fragmentation, effects the review stated had been "underestimated for a long time." Cognitive deficits, particularly in concentration and memory, appeared to persist after withdrawal. At the receptor level, the review detailed how CB1 receptors mediate THC's effects through G proteins, inhibiting calcium channels and stimulating potassium channels.

Specific attentional dysfunction in adults following early start of cannabis use.

Ehrenreich, H · 1999

Researchers hypothesized that cannabis exposure during a critical brain development period around puberty could cause lasting neural changes.

Reading and language in 9- to 12-year olds prenatally exposed to cigarettes and marijuana.

Fried, P A · 1997

Researchers examined reading and language abilities in 131 children aged 9-12 who were part of a longitudinal study tracking prenatal drug exposure from a predominantly middle-class population. Prenatal cigarette exposure showed a dose-dependent association with lower language and reading scores, even after controlling for potential confounders.

Differential impairments of selective attention due to frequency and duration of cannabis use.

Solowij, N · 1995

Building on their earlier ERP work, researchers studied long-term cannabis users while sober and identified two dissociable cognitive deficits that were affected by different patterns of use. The ability to focus attention and filter out irrelevant information, measured by frontal brain processing negativity, worsened progressively with the number of years of cannabis use but was unrelated to how often someone used.

Neurotoxicology of cannabis and THC: a review of chronic exposure studies in animals.

Scallet, A C · 1991

Multiple laboratories had reported that chronic exposure to THC or marijuana extracts produced persistent changes in the rat hippocampus, a brain region critical for learning and memory. The review identified two critical factors determining whether neurotoxic effects appeared: age during exposure and duration of exposure.

Health aspects of cannabis.

Hollister, L E · 1986

This extensive review examined cannabis health effects across virtually every organ system and population group. The review's central concern was youth: regular cannabis use might stunt emotional growth in adolescents, though whether the drug caused these effects or whether at-risk youth were drawn to use remained unclear.

Differential association between chronic cannabis use and brain function deficits.

Soueif, M I · 1976

Researchers administered 12 objective tests measuring psychomotor speed, distance and time estimation, memory, and visuomotor coordination to 850 regular cannabis users and 839 non-users. Cannabis users performed significantly worse than controls on most measures.

Adult Rat Offspring Exposed to THC during Gestation Exhibit Distinct Biomolecular Changes Identified by X-ray Fluorescence Imaging and Fourier Transform Infrared Spectroscopy in Cortico-Limbic Circuits.

Black, Tallan · 2026

Most prenatal cannabis studies measure outcomes at the behavioral or anatomical level.

Cannabidiol improves cognitive impairment after traumatic brain injury by attenuating neuronal oxidative stress and apoptosis via the SET/PP2A/Akt signaling axis.

Gao, Shan · 2026

CBD inhibited neuronal oxidative stress and apoptosis both in vivo and in vitro.

The Paradoxical Effect of Cannabis Use on Cognition in Chronic Psychotic Disorders.

Gorea, Fiorela · 2026

In 105 psychiatric inpatients with psychotic disorders, cannabis users had higher MoCA (Montreal Cognitive Assessment, a brief test of thinking skills) scores than non-users.

Identifying established human placental markers of schizophrenia in rodents after gestational ∆9-tetrahydrocannabinol exposure†.

Kocsis, Andrea M · 2026

This study tested whether prenatal THC exposure in rats would alter the same placental genes that human genomic studies have linked to schizophrenia risk.

High doses of orally administered cannabigerol produce deficits in sustained attention in female rats.

Moore, Catherine F · 2026

CBG at 300-600 mg/kg impaired sustained attention in female rats but not males.

Sex-dependent effects of ultra-low-dose-THC preventive treatment on neuroinflammation and cognitive decline in 5xFAD mice.

Nitzan, Keren · 2026

ULD-THC attenuated AD-related cognitive decline in both sexes.

The effects of chronic cannabidiol administration on brain pathology and behavioral deficits found in the tau P301s-line PS19 mouse model of Alzheimer's disease.

Nixon, Abigail G · 2026

CBD did not improve cognitive or motor behavior and did not restore hippocampal volume.

Cannabis Use in Older Individuals May Be an Important and Under-Recognized Risk Factor for Motor Vehicle Crashes.

Pearlson, Godfrey D · 2026

This paper synthesized evidence on a collision of trends: the growing population of adults over 65 who drive, increasing cannabis use among older adults for medical and recreational purposes, and age-related factors that may amplify cannabis impairment. Older drivers already have more crashes per mile driven and are more likely to be injured or killed in crashes of similar magnitude.

Prenatal and early postnatal cannabis exposure interactions with adolescent chronic stress on anxiety-like, depression-like, and risk-taking behaviour.

Peterson, Colleen S · 2026

Prenatal cannabis exposure alone did not significantly affect anxiety, stress coping, or social behavior.

Longer chronic cannabis use in humans is associated with impaired implicit motor learning and supranormal resting state cortical activity.

Prashad, Shikha · 2026

Comparing 30 regular cannabis users to 32 non-users, researchers found that longer duration of cannabis use was associated with a smaller implicit motor learning index — meaning these individuals were less able to unconsciously learn movement sequences. Implicit motor learning was measured using the serial reaction time task, where participants respond to visual cues that follow a hidden repeating pattern.

THC induced similar physiological effects on HIV transgenic rats and their controls without affecting HIV-induced deficits in effortful motivation.

Vemuri, Sunitha · 2026

THC at 3 mg/kg reduced pain sensitivity, body temperature, and locomotor activity across all genotypes, with some sex-dependent effects.

Sexually Dimorphic Effects of a Single Neonatal Δ9-tetrahydrocannabinol Exposure on Neuronal Dendritic Morphology and Cognitive Functions in Rats.

Wadhwa, Meetu · 2026

Rat pups received a single injection of THC (5 mg/kg) or vehicle at postnatal day 3 — a period corresponding to late pregnancy/early postnatal brain development in humans.

Combination treatment with medium dose THC and CBD had no therapeutic effect in a transgenic mouse model for Alzheimer's disease but affected other domains including anxiety-related behaviours and object recognition memory.

Aumer, Beate · 2025

Chronic treatment with 3 mg/kg THC and 20 mg/kg CBD did not improve anxiety-like behavior or object recognition deficits in 14.5-month-old Alzheimer's model mice.

Beneficial and adverse effects of THC on cognition in the HIV-1 transgenic rat model: Importance of exploring task- and sex-dependent outcomes.

Ayoub, Samantha M · 2025

Both acute and chronic THC exposure produced function-dependent effects in HIV-1 transgenic rats: learning improved but risk-based decision-making worsened.

Kynurenine amplifies tetrahydrocannabinol-induced sensorimotor impairment and classic "tetrad" effects in mice.

Bilel, Sabrine · 2025

Mice given kynurenine before THC showed significantly worse sensorimotor responses, greater motor impairment, and deeper hypothermia compared to THC alone.

Molecular pathogenesis of Alzheimer's disease onset in a mouse model: effects of cannabidiol treatment.

Bishara, Mary A · 2025

RNA sequencing identified over 1,000 differentially expressed markers of Alzheimer's disease onset in mice.

Low-dose cannabidiol treatment prevents chronic stress-induced phenotypes and is associated with multiple synaptic changes across various brain regions.

Borràs-Pernas, Sara · 2025

A very low dose of CBD (1 mg/kg) partially reversed behavioral effects of chronic stress in mice.

Heavy and Chronic Cannabis Addiction does not Impact Motor Function: A BOLD-fMRI Study.

Boujraf, Saïd · 2025

Three groups of cannabis users (heavy: 15 joints/day, moderate: 1.5 joints/day, light: 2.8 joints/week) plus healthy controls showed no significant differences in motor cortex activation patterns during fMRI-assessed motor tasks.

A behavioural and neurobiological assessment of effort-based decision-making in cannabis use disorder: An initial/preliminary investigation.

Brassard, Sarah L · 2025

The CUD group showed decreased ventromedial prefrontal cortex activity when initially evaluating effort and reward cues (Cue1), and increased activity in parietal, temporal, and cingulate regions during effort-reward integration (Cue2).

Prenatal Exposure to Vaporized High-Potency Cannabis Affects Hippocampal Synaptic Remodeling and Efficacy, Axonal Excitability, and Memory in Offspring.

Cairus, Andrea · 2025

Prenatal exposure to vaporized cannabis (14.7% THC) from gestational day 8 to 21 caused: increased synaptic vesicle recycling pools and vGlut1 abundance (presynaptic remodeling), downregulation of CB1 receptors at both excitatory and inhibitory synapses, increased axonal recruitment and synaptic efficacy at hippocampal CA1 synapses, and spatial memory deficits in both male and female adolescent offspring..

Divergent outcomes of delta 9 - tetrahydrocannabinol (THC) in adolescence on mesocortical dopamine and cognitive development in male and female mice.

Capolicchio, Tanya · 2025

In males, adolescent THC reduced dopamine axon volume in the medial prefrontal cortex and reduced presynaptic sites, while increasing dopamine innervation in the orbitofrontal cortex, suggesting axons were rerouted.

CB1 and CB2 receptors differentially modulate the cognitive impact of maternal immune activation and perinatal cannabinoid exposure.

Chen, Han-Ting · 2025

PCE impaired novel object recognition and working memory in males via CB1 receptors; MIA impaired the same tasks via CB2 receptors; combined PCE+MIA did not produce cognitive deficits; CB2 knockout prevented the protective effect of combined exposure..

Large-Scale Profiling of Coding and Long Noncoding Transcriptomes in the Hippocampus of Mice Acutely Exposed to Vaporized CBD or THC.

Choi, Mi Ran · 2025

THC upregulated glutamate receptor genes and downregulated dopamine genes (Drd1, Drd2, Gnal, Adcy5); CBD altered Wnt7a and Camk2b; most changes recovered by day 14 except Adcy5; lncRNA-mRNA correlations suggest regulatory mechanisms..

Cannabinoids Shape Synaptic Activity and Adult Neurogenesis in the Zebrafish Pallium.

Deleglise, Emilia Beatriz · 2025

CB1 receptors were found in glutamatergic neurons of the zebrafish pallium.

The effects of naturalistic cannabis use on cognition and subjective experience in older adults with normal cognitive function.

Di Ciano, P · 2025

Trail making test performance (versions A and B) was significantly decreased 60 minutes after smoking cannabis compared to the sober condition.

Effects of naturalistic doses of cannabis edibles on cognition and association with blood THC.

Di Ciano, Patricia · 2025

At 150 minutes after consuming a cannabis edible averaging 7.3 mg THC, participants showed decreased performance on two verbal free recall measures.

Obesogenic diet impairs memory consolidation via the hippocampal endocannabinoid system.

Ducourneau, Eva-Gunnel · 2025

Obesogenic diet consumption impaired long-term object recognition memory, and this was prevented by post-training CB1 receptor blockade, which also normalized hippocampal overactivation.

Muscarinic cannabinoid suppression of excitation, a novel form of coincidence detection.

Dvorakova, Michaela · 2025

Coincident activation of muscarinic acetylcholine receptors and endocannabinoid-mediated depolarization-induced suppression of excitation produced a ~40% inhibition of excitatory transmission lasting ~10 minutes.

Behavioral Decoding Reveals Cortical Endocannabinoid Potentiation during Δ9-THC Impairment.

English, Anthony · 2025

THC increased GABAergic (inhibitory) neuron activity in the medial prefrontal cortex before movement initiation, shifting the excitatory/inhibitory balance.

Exploratory study on plasma Acylglycerol and Acylethanolamide dysregulation in substance use and attention-deficit/hyperactivity disorder: Implications for novel biomarkers in dual diagnosis.

Flores-López, María · 2025

SUD patients had lower plasma 2-AG and 2-LG and elevated acylethanolamides vs controls.

Lifelong dietary Omega-3, -6, and -9 ratios shape adult behavior and response to adolescent THC exposure in rats.

Frajerman, Ariel · 2025

In 164 rats fed omega-3, -6, or -9 enriched diets from conception, diet significantly affected social behavior, anxiety, cognitive flexibility, and impulse control.

Cannabidiol improves learning and memory deficits and alleviates anxiety in 12-month-old SAMP8 mice.

Goodland, Monica N · 2025

In SAMP8 mice (a model for Alzheimer's disease), high-dose CBD (30 mg/kg daily for two months) significantly improved learning and memory in T-maze and novel object recognition tests.

Adolescents and cannabis in the 21st century: Current Problems in Pediatric and Adolescent Health Care.

Itriyeva, Khalida · 2025

This comprehensive review covers three decades of adolescent cannabis trends in the United States, and the picture it paints is more complicated than either "legalization is harmless" or "legalization is catastrophic" narratives suggest. Teenage use rates have remained remarkably stable despite legalization.

Recreational substance use is linked with difficulty in recalling personal experiences.

Levent, Adnan · 2025

Participants who reported recreational substance use recalled significantly fewer specific autobiographical memories than non-users and were more likely to omit responses entirely.

Bridging THC Knowledge Gaps for Safer Roads: A Call for Action.

Li, Peizhi · 2025

This commentary cuts to the heart of a policy problem: states are setting cannabis driving laws without the science to back them up.

An astrocytic ensemble at vHip-NAc synapses modulates cognitive impairments induced by chronic tetrahydrocannabinol exposure.

Martín-Monteagudo, Cristina · 2025

THC increased astrocytic calcium activity and glutamate release in the nucleus accumbens via the ventral hippocampus circuit.

Suk-SaiYasna Remedy, a Traditional Thai Medicine, Mitigates Stress-Induced Cognitive Impairment via Keap1-Nrf2 Pathway.

Masraksa, Wuttipong · 2025

SSY treatment significantly improved learning and memory in chronically stressed mice across three behavioral tests (Y-maze, novel object recognition, Morris water maze).

Cannabinoids and ADHD: a New Frontier in Neuropharmacology?

Mavaddat, Helia · 2025

Individuals with ADHD have elevated risk for substance use and cannabis dependence.

Missouri College Students' Intentions Towards Initiating or Changing Cannabis Use in a Shifting Legal Landscape.

McNamara, Ian A · 2025

Following the 2022 legalization of recreational cannabis in Missouri, college students showed increased intentions to use cannabis and more favorable attitudes compared to pre-legalization baseline data..

Relation of Cannabis Use Frequency and Gambling Behavior in Individuals Who Gamble Under the Influence of Cannabis.

McPhail, Abby · 2025

Higher frequency of cannabis use was associated with greater gambling involvement, pointing to shared behavioral or neurobiological risk factors between the two behaviors..

Chronic cannabis use in people with bipolar disorder is associated with comparable decision-making and functional outcome to healthy participants.

Miranda, Alannah · 2025

Among 87 participants, people with bipolar disorder who used cannabis regularly (4+ times/week) performed comparably to healthy non-users on decision-making and functional capacity measures.

Effects of cannabidiol (CBD) treatment on age-related cognitive decline in C57 mice.

Mirza Agha, Behroo · 2025

Fourteen-month-old mice given oral CBD for 7 months showed reduced inflammatory response in the brain and improvements in age-related cognitive decline when tested between 19-21 months of age across tasks measuring perirhinal cortex, hippocampal, amygdala, and motor function..

Structural changes of tubulin by interacting with Δ9-tetrahydrocannabinol: in-vitro and theoretical studies.

Mohammadkhani, Mina · 2025

THC reduced microtubule polymerization in a concentration-dependent manner and caused significant changes in tubulin secondary structure as measured by circular dichroism spectroscopy.

Cannabinoid agonist WIN55,212-2 prevents scopolamine-induced impairment of spatial memory in rats.

Moreno-Rodríguez, Marta · 2025

Subchronic low-dose WIN55,212-2 (0.5 mg/kg) prevented scopolamine-induced spatial memory impairment in Barnes maze testing.

Cannabis use and cognition in older adults: Preliminary performance-based neuropsychological test results and directions for future research.

Mulhauser, Kyler · 2025

As cannabis use increases among older adults, a pressing question is whether it affects cognitive function in people already at risk for or experiencing cognitive decline.

The impact of cannabis use on ageing and longevity: a systematic review of research insights.

Nain, Sonam · 2025

Eleven preclinical studies showed promising results for cannabinoids in aging, including improved lifespan, cognitive function, reduced inflammation, better sleep, and enhanced social interaction.

Long-term cannabinoid therapy can ameliorate chronic sleep deprivation-induced behavioral and neuroinflammatory changes in mice.

Niazi, Nasar Ullah Khan · 2025

Chronic sleep deprivation caused memory impairment, depression-like behavior, microglial activation, and elevated pro-inflammatory cytokines in mice.

Chronic exposure to a synthetic cannabinoid improves cognition and increases locomotor activity in Tg4-42 Alzheimer's disease mice.

Ott, Frederik W · 2025

Therapeutic WIN 55,212-2 treatment rescued recognition memory and spatial reference deficits.

Biochemical Role of the Endocannabinoid System in the Pathophysiology of Attention Deficit Hyperactivity Disorder: A Narrative Review and Future Directions.

Özmeral Erarkadaş, Kübra · 2025

Eleven preclinical and 2 clinical studies showed alterations in endocannabinoid system components linked to ADHD-related behaviors.

Acute effects of Δ9-tetrahydrocannabinol on computational measures of neurocognitive processes are related to recent cannabis use among adolescents and young adults.

Paige, K J · 2025

Overall, 7.5mg oral THC did not significantly alter cognitive performance compared to placebo.

Daily Cannabis Use: Do Impulsivity and Sensation Seeking Predict Negative Cannabis Related Consequences?

Parnes, Jamie E · 2025

Among daily legal cannabis users, risk-seeking personality was significantly positively associated with negative cannabis-related consequences.

Acute cannabidiol treatment reverses behavioral impairments induced by embryonic valproic acid exposure in male mice.

Pedrazzi, J F C · 2025

In mice prenatally exposed to valproic acid (a model of autism), acute CBD at 30-60 mg/kg reversed pre-pulse inhibition deficits, decreased repetitive marble-burying, improved social interaction time, and restored object recognition memory.

Age- and sex-dependent participation of the endocannabinoid system in locomotion and risk assessment of an ADHD rat model.

Penna, Daniel Bussinger de Souza · 2025

During adolescence, cannabinoid receptor activation aggravated hyperactivity and risky behaviors in ADHD model rats, with more pronounced effects in females.

"Modulatory role of baseline impulsivity on the acute and persistent effects of CB1 agonism on impulsive choice".

Pérez-Valenzuela, Enzo · 2025

The CB1/2 receptor agonist WIN 55,212-2 reduced impulsive choice in rats classified as highly impulsive but had no effect in low-impulsivity rats.

Effects of cannabidiol on behavioral and psychological symptoms of vascular dementia: A randomized, double-blind, placebo-controlled clinical trial.

Pessoa, Rebeca Mendes P · 2025

CBD (300 mg/day for 4 weeks) significantly reduced scores on both the Neuropsychiatric Inventory (NPI, p=0.05) and the Brief Psychiatric Rating Scale (BPRS, p<0.05) compared to placebo.

Timing matters: modeling the effects of gestational cannabis exposure on social behavior and microglia in the developing amygdala.

Pham, Aidan L · 2025

Cannabis is the most commonly used illicit drug during pregnancy, with rates rising as legalization expands.

The unmet need for cannabis use disorder treatment in multiple sclerosis: Insights from a nationwide pilot study.

Pilloni, Giuseppina · 2025

More than half of individuals with MS use cannabis, with up to 20% at risk for cannabis use disorder.

Telehealth tDCS to reduce cannabis use: A pilot RCT in multiple sclerosis as a framework for generalized use.

Pilloni, Giuseppina · 2025

The active tDCS group showed significant reductions in weekly cannabis use (5.3 to 3.9 days, p=0.014) and withdrawal symptoms (CWS, p<0.001).

Attentional bias in people with moderate-to-severe cannabis use disorder.

Quinones-Valera, Marianna · 2025

Among 66 people with moderate-to-severe CUD and 42 controls, there were no significant group differences in attentional bias toward cannabis images using a visual probe task.

Cannabidiol as a multifaceted therapeutic agent: mitigating Alzheimer's disease pathology and enhancing cognitive function.

Raïch, Iu · 2025

In the 5xFAD Alzheimer's mouse model, CBD decreased pTau and amyloid-beta aggregation, reduced their transport between brain regions, shifted microglia toward a neuroprotective M2 phenotype, reduced inflammatory cytokine release, and partially reversed neurite formation loss.

Altered Network Function in Hippocampus After Sub-Chronic Activation of Cannabinoid Receptors in Early Adolescence.

Rehn, Johanna · 2025

The hippocampus—the brain's memory center—has an unusually high density of CB1 cannabinoid receptors.

Altered network function in hippocampus after sub-chronic activation of Cannabis receptors in peri-adolescence.

Rehn, Johanna · 2025

This is the preprint (bioRxiv) version of the study published as RTHC-00197.

Efficacy of a neuroscience informed psychoeducation intervention on cognitive, emotional, and substance use outcomes in college students: a pilot study.

Rezapour, Tara · 2025

After four 20-minute NIPA sessions, 68 college students showed significant reductions in executive function deficits, stress, and anxiety.

Cannabinoid type 1 receptors in the mice prefrontal cortex regulate object location memory acquisition via GABAergic neurons.

Tokutake, Tomohiro · 2025

This study zeroed in on a specific question: which phase of memory does THC-like activation in the prefrontal cortex disrupt, and through what mechanism? The researchers injected a CB1 receptor agonist (ACPA) directly into the prefrontal cortex of mice before different stages of two memory tests.

Unraveling Cannabidiol's Dual Modulatory Role in Schizophrenia: Network Pharmacology and In Vivo Validation of Neuroinflammatory and Behavioral Modulation.

Wei, Ying · 2025

RTHC-00193 reviewed clinical evidence that CBD may have therapeutic potential for schizophrenia.

Neurodevelopmental effects of exogenous cannabinoids on endocannabinoid and GABAergic neurotransmission.

Wiley, Miles T · 2025

This review presents a fascinating and underappreciated mechanism by which prenatal cannabis could affect brain development: the GABA switch. Here's the background: during early brain development, GABA—which becomes the brain's primary inhibitory neurotransmitter in adults—actually functions as an excitatory signal.

Unveiling the link between chronic pain and misuse of opioids and cannabis.

Dagher, Merel · 2024

Over 50 million Americans live with chronic pain, and many don't receive adequate treatment.

Differential disruption of response alternation by precipitated Δ9-THC withdrawal and subsequent Δ9-THC abstinence in mice.

Eckard, Matthew L · 2024

After 5 days of twice-daily THC (10 mg/kg), rimonabant-precipitated withdrawal caused longer session times, longer response latencies, more errors, and slower error correction in THC-treated mice.

Evaluation of three-year neurodevelopmental outcomes in infants prenatally exposed to substance use.

Jarque, Pilar · 2024

Among 32 prenatally exposed and 32 matched control infants assessed at 36 months using the Bayley Scales, exposed infants scored significantly lower in cognitive, motor, and language domains.

Cannabidiol and positive effects on object recognition memory in an in vivo model of Fragile X Syndrome: Obligatory role of hippocampal GPR55 receptors.

Manduca, Antonia · 2024

CBD corrected short-term recognition memory deficits in Fmr1 knockout rats.

Cannabidiol and Alzheimer's disease.

Marques, Bruno L · 2024

Preclinical studies show CBD can mitigate cognitive decline and amyloid-beta-induced neurodegeneration through modulation of oxidative stress and neuroinflammation.

Fetal Cannabinoid Syndrome: Behavioral and Brain Alterations of the Offspring Exposed to Dronabinol during Gestation and Lactation.

Navarro, Daniela · 2024

Offspring exposed to dronabinol (10 mg/kg twice daily) from gestational day 5 through postnatal day 21 displayed increased anxiogenic and depressive-like behaviors, cognitive impairment, disrupted reward system function, and increased alcohol consumption motivation at postnatal day 60.

Vaporized Δ9-tetrahydrocannabinol exposure in utero has negative effects on attention in a dose- and sex-dependent manner.

Penman, Samantha L · 2024

Rats exposed to low-dose vaporized THC (10 mg) during pregnancy showed significantly decreased object exploration in both novel object recognition and object-based attention tests, indicating reduced attention.

Timeframe Analysis of Novel Synthetic Cannabinoids Effects: A Study on Behavioral Response and Endogenous Cannabinoids Disruption.

Pineda Garcia, Jorge Carlos · 2024

All three synthetic cannabinoids (MDMB-CHMINACA, 5F-ADB-PINACA, APICA) caused locomotor disruption and sustained anxiety at all time points (1, 3, 5 hours).

Exploring Cannabinoids with Enhanced Binding Affinity for Targeting the Expanded Endocannabinoid System: A Promising Therapeutic Strategy for Alzheimer's Disease Treatment.

Stanciu, Gabriela Dumitrita · 2024

Chronic treatment with JWH-133 (a selective CB2 agonist) and Cannabis sativa extract reduced anxiety-like behavior and partially reversed recognition memory deficits in APP/PS1 mice.

Metabotropic Glutamate Receptor 5 as a Potential Biomarker of the Intersection of Trauma and Cannabis Use.

Weiss, Emily R · 2024

The endocannabinoid system and the glutamate system are deeply intertwined in the brain, and both are implicated in trauma-related conditions and cannabis use.

Cannabis smoke and oral Δ9THC enhance working memory in aged but not young adult subjects.

Zequeira, Sabrina · 2024

Acute cannabis smoke enhanced working memory in aged male rats but impaired it in aged females, with no effects in young adults of either sex.

Alcohol and cannabinoid binges and daily exposure to nicotine in adolescent/young adult rats induce sex-dependent long-term appetitive instrumental learning impairment.

Abela, Norbert · 2023

Female rats showed impaired food-reward learning on both easy (FR1) and harder (FR2) tasks, while males showed impairment only on the harder FR2 task.

Effort-related decision making and cannabis use among college students.

Acuff, Samuel F · 2023

Greater cannabis use days and cannabis use disorder symptoms predicted increased likelihood of selecting high-effort trials on the EEfRT, even after controlling for ADHD symptoms, distress tolerance, income, and delay discounting.

A Semi-Naturalistic, Open-Label Trial Examining the Effect of Prescribed Medical Cannabis on Neurocognitive Performance.

Arkell, Thomas R · 2023

Participants' performance improved over time on the CANTAB Multitasking Test and Rapid Visual Information Processing test.

Role of cyclin-dependent kinase 5 in psychosis and the modulatory effects of cannabinoids.

Barrera-Conde, Marta · 2023

First-episode psychosis patients with prior cannabis use (FEP/c) had lower CDK5 and higher PSD95 levels compared to those without cannabis use (FEP/nc), and showed fewer social functioning deficits.

Cognitive dysfunction and impaired neuroplasticity following repeated exposure to the synthetic cannabinoid JWH-018 in male mice.

Bilel, Sabrine · 2023

Repeated JWH-018 treatment (6 mg/kg daily for 7 days) induced psychomotor agitation, reduced social dominance and recognition memory, impaired prepulse inhibition, disrupted hippocampal long-term potentiation, decreased BDNF expression, and altered endocannabinoid system components in the striatum and hippocampus, all persisting 15+ days after last exposure..

Chronic exposure to a synthetic cannabinoid alters cerebral brain metabolism and causes long-lasting behavioral deficits in adult mice.

Bouter, Caroline · 2023

Treatment with WIN 55,212-2 (3 mg/kg) led to hypometabolism in the hippocampus, cerebellum, amygdala, and midbrain, persisting even after prolonged abstinence.

Divergent effects of oral cannabis oil extracts marketed as C. indica or C. sativa on exertion of cognitive effort in rats.

Brodie, Hannah G · 2023

Both cannabis products (matched for THC and CBD content) slowed response times at higher doses, but only the indica-labeled oil at 10 mg/kg THC reduced the proportion of trials where rats chose high-effort/high-reward options.

CBD enhances the cognitive score of adolescent rats prenatally exposed to THC and fine-tunes relevant effectors of hippocampal plasticity.

Castelli, Valentina · 2023

Prenatal THC exposure (2 mg/kg, gestational days 5-20) impaired spatial and configural memory and disrupted hippocampal plasticity markers in adolescent rats.

Self-Regulation of Driving Behavior Under the Influence of Cannabis: The Role of Driving Complexity and Driver Vision.

Ortiz-Peregrina, Sonia · 2023

After smoking cannabis, visual acuity and contrast sensitivity were significantly impaired.

Use of cannabidiol (CBD) for the treatment of cognitive impairment in psychiatric and neurological illness: A narrative review.

Ortiz, Rachel · 2023

Preclinical studies demonstrated CBD improved cognitive performance in animal models of schizophrenia, epilepsy, Alzheimer's, and others.

Effects of prenatal exposure to THC on hippocampal neural development in offspring.

Peng, Hao · 2023

THC administration during gestational days 5.5-12.5 altered neuronal cell composition in offspring hippocampus at PND21.

Prenatal Cannabinoid Exposure Elicits Memory Deficits Associated with Reduced PSA-NCAM Expression, Altered Glutamatergic Signaling, and Adaptations in Hippocampal Synaptic Plasticity.

Pinky, Priyanka D · 2023

Prenatal WIN55,212-2 caused hippocampal-dependent memory deficits in adolescent offspring associated with decreased long-term potentiation, enhanced long-term depression, and imbalanced GluN2A/GluN2B signaling.

Mechanisms of cannabinoid tolerance.

Piscura, Mary K · 2023

Anyone who uses cannabis regularly knows tolerance is real: the same dose produces weaker effects over time.

CBD lengthens sleep but shortens ripples and leads to intact simple but worse cumulative memory.

Samanta, Anumita · 2023

CBD extended the sleep period but changed properties of rest and non-REM sleep oscillations (delta, spindle, ripples).

Repeated Exposure to High-THC Cannabis Smoke during Gestation Alters Sex Ratio, Behavior, and Amygdala Gene Expression of Sprague Dawley Rat Offspring.

Sandini, Thaisa M · 2023

Cannabis smoke exposure during pregnancy caused a significant increase in male-to-female ratio in litters.

Experience with dronabinol consumption facilitated a stimulant effect of alcohol and affected alcohol-related changes in frontal cortical endocannabinoid levels in male rats.

Sangiamo, Daniel T · 2023

Adolescent edible THC experience facilitated alcohol-induced increases in moving speed on a maze.

The Effect of Cannabidiol Coated by Nano-Chitosan on Learning and Memory, Hippocampal CB1 and CB2 Levels, and Amyloid Plaques in an Alzheimer's Disease Rat Model.

Amini, Mohammadali · 2022

Nano-chitosan-coated CBD significantly reduced escape latency and travel distance in memory tests while increasing time in the target zone.

The different role of G-protein-coupled receptor 30 (GPR30) in the interaction effects of marijuana and estradiol on spatial learning and memory at different ages.

Chahkandi, Mohadeseh · 2022

Marijuana alone improved spatial learning in both young and old female rats.

Clinical and cognitive improvement following full-spectrum, high-cannabidiol treatment for anxiety: open-label data from a two-stage, phase 2 clinical trial.

Dahlgren, Mary Kathryn · 2022

Anxiety scores decreased significantly by week 4 (BAI: p<0.001; OASIS: p<0.001).

Management of Hyperhomocysteinemia, Low Vitamin Levels, and Low Cortisol in Cannabis Users: A Report of 2 Cases.

de Carvalho, Jozélio · 2022

Both patients, who had used cannabis for 9 and 14 years respectively, had abnormal blood levels of homocysteine, vitamins, and cortisol.

The role of cannabinoids in neurodevelopmental disorders of children and adolescents.

Dias-de Freitas, F · 2022

CBD modulates the endocannabinoid system in developing brains through multiple mechanisms and appears to have anxiolytic, antipsychotic, and neuroprotective properties.

Chronic use of cannabis might impair sensory error processing in the cerebellum through endocannabinoid dysregulation.

F Amil, Adrián · 2022

Chronic cannabis use causes CB1 receptor downregulation in the cerebellum, which the researchers propose leads to a generalized underestimation of sensory errors.

Workplace Cannabis Policies: A Moving Target.

Hazle, Mia C · 2022

The legal landscape for workplace cannabis use is a mess.

Attention-Deficit Hyperactivity Disorder and Therapeutic Cannabis Use Motives.

Hernandez, Mariely · 2022

Individuals with ADHD may be at increased risk of cannabis use problems due to deficits in self-regulation.

Thalamocortical functional connectivity and cannabis use in men with childhood attention-deficit/hyperactivity disorder.

Lee, Sanghyun · 2022

Cannabis-using adults with childhood ADHD (n=18) had significantly decreased thalamic-parietal functional connectivity compared to non-users (n=15).

Cannabinoids for behavioral symptoms in severe dementia: Safety and feasibility in a long-term pilot observational study in nineteen patients.

Pautex, Sophie · 2022

Managing behavioral symptoms in severe dementia — agitation, aggression, wandering, sleep disruption — is one of the hardest challenges in elder care.

Multimodal Correlates of Cannabis Use among U.S. Veterans with Bipolar Disorder: An Integrated Study of Clinical, Cognitive, and Functional Outcomes.

Selloni, Alexandria · 2022

Current cannabis use in veterans with bipolar I disorder was associated with higher working memory performance and higher functional capacity compared to both past cannabis users and non-users, while also being associated with PTSD and lifetime suicidal ideation..

White Matter Microstructure and Gray Matter Volume in Cannabis-Induced Psychosis and Schizophrenia With Cannabis Use.

Shah, Raghav · 2022

Participants with schizophrenia and cannabis use (SZC) had widespread white matter microstructural abnormalities, while those with cannabis-induced psychosis (CIP) had fewer WM disruptions and greater gray matter volumes in the cerebellum and frontal regions..

Administration of Δ9-Tetrahydrocannabinol Following Controlled Cortical Impact Restores Hippocampal-Dependent Working Memory and Locomotor Function.

Song, Shijie · 2022

THC-treated mice exhibited marked improvement in Y-maze working memory performance and recovered to normal rotarod performance by 2 weeks after brain injury.

Using ecological momentary assessment and a portable device to quantify standard tetrahydrocannabinol units for cannabis flower smoking.

Trull, Timothy J · 2022

One of the biggest problems in cannabis research is that 'a joint' can contain wildly different amounts of THC depending on the flower's potency and how much is used.

DNA methylation changes associated with cannabis use and verbal learning performance in adolescents: an exploratory whole genome methylation study.

Wiedmann, Melina · 2022

Six CpG methylation sites showed reduced methylation associated with the extent of chronic cannabis use.

The role of endocannabinoid pathway in the neuropathology of Alzheimer's disease: Can the inhibitors of MAGL and FAAH prove to be potential therapeutic targets against the cognitive impairment associated with Alzheimer's disease?

Bajaj, Shivanshu · 2021

MAGL and FAAH inhibitors have shown potential to protect neurons from amyloid-beta toxicity, reduce tau phosphorylation, combat oxidative stress, and stimulate neurotrophins that support brain repair.

Alcohol and Cannabis Use Disorder Symptom Severity, Conduct Disorder, and Callous-Unemotional Traits and Impairment in Expression Recognition.

Blair, Robert James R · 2021

Cannabis use disorder severity was negatively associated with recognition accuracy for higher-intensity sad and fearful expressions, while conduct disorder was independently associated with reduced sad expression recognition.

Disrupted parahippocampal and midbrain function underlie slower verbal learning in adolescent-onset regular cannabis use.

Blest-Hopley, Grace · 2021

Cannabis users showed significantly slower learning across repeated trials (p = 0.032).

Perceived effects of cannabis and changes in driving performance under the influence of cannabis.

Burt, Thomas S · 2021

Subjective cannabis effects predicted changes in driver inputs (steering frequency, reversal rate), while actual driving performance measures like lane weaving were better predicted by dosing condition.

Neurodevelopmental Effects of Cannabis Use in Adolescents and Emerging Adults with ADHD: A Systematic Review.

Cawkwell, Philip B · 2021

No study found an additive or interaction effect between ADHD and cannabis use on neuropsychological tasks of executive function.

Effectiveness of Cannabinoids for Treatment of Dementia: A Systematic Review of Randomized Controlled Trials.

Charernboon, Thammanard · 2021

Nabilone (1-2 mg/day) showed significant improvement in agitation in one trial.

Anti-Inflammatory Effects of Fatty Acid Amide Hydrolase Inhibition in Monocytes/Macrophages from Alzheimer's Disease Patients.

Chiurchiù, Valerio · 2021

AD patients had lower CB1 and CB2 expression on B-lymphocytes and monocytes, with higher FAAH levels in monocytes.

Cognitive performance and lifetime cannabis use in patients with first-episode schizophrenia spectrum disorder.

Hájková, M · 2021

First-episode schizophrenia patients with lifetime cannabis use (n=30) showed better cognitive performance than non-using patients (n=53), with the most prominent difference in visual memory.

Cannabidiol enhances verbal episodic memory in healthy young participants: A randomized clinical trial.

Hotz, Janine · 2021

CBD enhanced verbal episodic memory performance compared to placebo (7.71 vs.

The relationship between cannabis use and cognition in people with bipolar disorder: A systematic scoping review.

Jordan Walter, T · 2021

Of 6 qualifying studies, two found cannabis use in bipolar disorder was associated with better performance in some cognitive domains, three found no association, and one found worse overall cognition.

Cannabidiol Exposure During the Mouse Adolescent Period Is Without Harmful Behavioral Effects on Locomotor Activity, Anxiety, and Spatial Memory.

Kaplan, J S · 2021

Prolonged adolescent CBD exposure (20 mg/kg twice daily, days 25-45) had no detrimental effects on locomotor activity, anxiety behavior (elevated plus maze), or spatial memory (Barnes Maze) compared to vehicle-treated mice.

Cognitive and affective responses to marijuana prevention and educational messaging.

Leshner, Glenn · 2021

Driving-themed prevention messages from two different campaigns consistently produced the greatest cognitive resource allocation, highest arousal, and most positive emotional responses, as measured by heart rate, skin conductance, and facial action coding..

Occipital neural dynamics in cannabis and alcohol use: independent effects of addiction.

Lew, Brandon J · 2021

Participants meeting criteria for alcohol use disorder displayed significantly blunted occipital alpha (8-16 Hz) responses during visual-spatial processing, and this effect scaled with AUD symptom severity.

Chronic cannabis smoking-enriched oral pathobiont drives behavioral changes, macrophage infiltration, and increases β-amyloid protein production in the brain.

Luo, Zhenwu · 2021

Cannabis smokers showed oral microbial dysbiosis with increased Streptococcus and Actinomyces and decreased Neisseria.

Naturalistic exploratory study of the associations of substance use on ADHD outcomes and function.

MacDonald, Benjamin · 2021

ADHD patients with comorbid substance use disorders scored significantly lower on objective cognitive testing (IVA/CPT, P < 0.0001).

Emotion regulation in emerging adults with major depressive disorder and frequent cannabis use.

Nichols, Emily S · 2021

MDD showed an interaction with emotion regulation in the middle temporal gyrus, while cannabis use showed an interaction in the superior temporal gyrus.

Sociodemographic and clinical profile of cannabis-induced psychosis: A comparative study.

Padhi, Debasish · 2021

Cannabis-using patients with psychosis showed higher scores in pressure of speech, distractible speech, and clanging.

Do neurocognitive functions in cannabis induced psychosis groups differ from schizophrenia with cannabis use? A controlled cross-sectional study.

Shah, Raghav · 2021

With 20 matched participants per group, cannabis-induced psychosis patients performed significantly better than schizophrenia-with-cannabis patients on general intelligence and attention tests, and showed cognitive deficits only in some executive function domains compared to healthy controls..

Increased Likelihood of Falling in Older Cannabis Users vs. Non-Users.

Workman, Craig D · 2021

Cannabis-using older adults showed higher fall risk scores, poorer one-leg standing balance, and slower gait speed compared to matched non-users.

Developmental differences in the effects of CB1/2R agonist WIN55212-2 on extinction of learned fear.

Bisby, Madelyne A · 2020

WIN55212-2, a CB1/CB2 receptor agonist, improved fear extinction in adult rats but impaired extinction acquisition in both adolescent and juvenile rats.

The effects of acute cannabidiol on cerebral blood flow and its relationship to memory: An arterial spin labelling magnetic resonance imaging study.

Bloomfield, Michael A P · 2020

CBD increased cerebral blood flow in the hippocampus by an average of 15 mL/100g/min compared to placebo (Cohen's d = 0.75, p = 0.004).

In utero Δ9-tetrahydrocannabinol exposure confers vulnerability towards cognitive impairments and alcohol drinking in the adolescent offspring: Is there a role for neuropeptide Y?

Brancato, Anna · 2020

In utero THC-exposed adolescent rats showed impaired aversive limbic memory (but intact neutral memory), decreased NPY-positive neurons in limbic regions, altered Homer protein expression, and increased alcohol consumption, relapse, and compulsive-like drinking behavior in operant chambers..

EEG biomarkers acquired during a short, straight-line simulated drive to predict impairment from cannabis intoxication.

Brown, Timothy L · 2020

Standard deviation of lane position (SDLP) was significantly worse and heart rate elevated during THC sessions compared to placebo.

Mobile Assessment of Acute Effects of Marijuana on Cognitive Functioning in Young Adults: Observational Study.

Chung, Tammy · 2020

Higher subjective marijuana ratings were associated with slower reaction times on all three mobile tasks (Flowers: B=2.29, p=.008; Stroop: B=2.74, p=.01; DSST: B=3.08, p=.03) and fewer correct responses on two of three tasks.

Recreational cannabis use impairs driving performance in the absence of acute intoxication.

Dahlgren, M Kathryn · 2020

Cannabis users showed increased accidents, speed, lateral movement, and reduced rule-following compared to controls.

Long-term hippocampal interneuronopathy drives sex-dimorphic spatial memory impairment induced by prenatal THC exposure.

de Salas-Quiroga, Adán · 2020

Adult male mice exposed to THC prenatally showed altered hippocampal oscillations, brain hyperexcitability, and spatial memory impairment.

The relationship between cannabis use and cognition in people diagnosed with first-episode psychosis.

de Vos, Chloé · 2020

Of 89 FEP patients, 61 (68.5%) were lifetime cannabis users.

Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study.

Delvecchio, Giuseppe · 2020

CIP patients showed extensive grey matter decreases in right superior frontal gyrus, precentral, superior temporal gyrus, bilateral insula, right precuneus, right medial occipital gyrus, right fusiform gyrus, and left hippocampus compared to non-psychotic chronic cannabis users.

Combined neurotoxic effects of cannabis and nandrolone decanoate in adolescent male rats.

El-Shamarka, Marwa El-Sayed · 2020

Combined cannabis + nandrolone caused learning/spatial memory deficits, hypo-locomotion, anxiety, and aggression.

Disease-modifying effects of natural Δ9-tetrahydrocannabinol in endometriosis-associated pain.

Escudero-Lara, Alejandra · 2020

THC alleviated mechanical pain hypersensitivity, reduced pain unpleasantness, restored memory deficits, and inhibited the growth of endometrial cysts.

Cannabinoid and Terpenoid Doses are Associated with Adult ADHD Status of Medical Cannabis Patients.

Hergenrather, Jeffrey Y · 2020

Higher cannabis dose consumers and those with lower ADHD symptom scores more frequently reported stopping all ADHD medications.

Paternal factors in neurodevelopmental toxicology: THC exposure of male rats causes long-lasting neurobehavioral effects in their offspring.

Holloway, Zade R · 2020

Offspring of THC-exposed fathers showed adolescent hyperactivity (at 2 mg/kg dose), faster decline in novel object interest (at 2 mg/kg), and delayed radial-arm maze learning (at 4 mg/kg).

CB1 Activity Drives the Selection of Navigational Strategies: A Behavioral and c-Fos Immunoreactivity Study.

Laricchiuta, Daniela · 2020

Mice treated with CB1 antagonist AM251 showed impaired spatial learning on a Circular Hole Board task and shifted their navigation strategy patterns.

Activation of cannabinoid type 1 receptors decreases the synchronization of local field potential oscillations in the hippocampus and entorhinal cortex and prolongs the interresponse time during a differential-reinforcement-of-low-rate task.

Liao, Wan-Ting · 2020

CB1 receptor activation in the medial entorhinal cortex reduced gamma amplitude synchronization and theta-gamma coupling between the hippocampal CA1 region and MEC.

Treadmill exercise improves LPS-induced memory impairments via endocannabinoid receptors and cyclooxygenase enzymes.

Moosavi Sohroforouzani, Azam · 2020

Rats with LPS-induced neuroinflammation showed cognitive impairment in the water maze.

Effects of Smoking Cannabis on Visual Function and Driving Performance. A Driving-Simulator Based Study.

Ortiz-Peregrina, Sonia · 2020

In 20 young drivers, smoking cannabis significantly worsened visual acuity, contrast sensitivity, and stereoacuity (depth perception).

Chronic cannabidiol (CBD) treatment did not exhibit beneficial effects in 4-month-old male TAU58/2 transgenic mice.

Watt, Georgia · 2020

TAU58/2 transgenic mice showed reduced body weight, reduced anxiety, impaired motor function, and increased freezing in fear conditioning compared to wildtype.

Cannabidiol improves vocal learning-dependent recovery from, and reduces magnitude of deficits following, damage to a cortical-like brain region in a songbird pre-clinical animal model.

Alalawi, Ali · 2019

CBD at 10 and 100 mg/kg effectively reduced the time required to recover vocal phonology and syntax after brain microlesions in zebra finches.

Altered motor development following late gestational alcohol and cannabinoid exposure in rats.

Breit, Kristen R · 2019

Cannabinoid exposure (CP-55,940) during the brain growth spurt accelerated early motor development while alcohol delayed it.

Effects in rats of adolescent exposure to cannabis smoke or THC on emotional behavior and cognitive function in adulthood.

Bruijnzeel, Adriaan W · 2019

Despite testing both cannabis smoke and THC at multiple doses during the adolescent period (P29-49 or P35-45), adult rats showed no significant effects on anxiety (open field, elevated plus maze), depression (sucrose preference, forced swim), or cognition (novel object recognition) after abstinence until P70.

Heavy Cannabis Use Associated with Wernicke's Encephalopathy.

Chaudhari, Amit · 2019

The patient presented with seizures secondary to cannabis hyperemesis-induced vomiting and hyponatremia.

Cortical Thickness and Subcortical Volumes in Adolescent Synthetic Cannabinoid Users with or Without ADHD: a Preliminary Study.

Çolak, Çiğdem · 2019

SC users with and without ADHD had reduced cortical thickness in left caudal middle frontal and left superior frontal areas compared to controls.

Sex, THC, and hormones: Effects on density and sensitivity of CB1 cannabinoid receptors in rats.

Farquhar, Charlotte E · 2019

Researchers gave male and female rats twice-daily THC injections for a week and then measured CB1 receptor density and function across four brain regions: cerebellum, hippocampus, prefrontal cortex, and striatum.

Medical Cannabis for Adult Attention Deficit Hyperactivity Disorder: Sociological Patient Case Report of Cannabinoid Therapeutics in Finland.

Hupli, Aleksi Mikael Markunpoika · 2019

After experiencing adverse effects from methylphenidate and alternative medications, the patient was prescribed Bedrocan (THC-dominant) for ADHD symptom relief and Bediol (THC+CBD) to moderate the THC effects and improve sleep.

Effects of the synthetic cannabinoid 5F-AMB on anxiety and recognition memory in mice.

Ito, Shiho · 2019

Central 5F-AMB produced anxiolytic effects and impaired recognition memory acquisition via CB1 receptors (blocked by AM251).

Effects of chronic cannabinoid exposure during adolescence on reward preference and mPFC activation in adulthood.

Jacobs-Brichford, Eliza · 2019

Adult rats that received WIN 55,212-2 during adolescence (postnatal days 30-60) showed subtle changes in choice behavior and significantly reduced mPFC neural activity during lever presses and reward delivery in a probabilistic reward task, suggesting impaired excitatory-inhibitory balance from adolescent exposure..

Adolescent Δ9-Tetrahydrocannabinol Exposure and Astrocyte-Specific Genetic Vulnerability Converge on Nuclear Factor-κB-Cyclooxygenase-2 Signaling to Impair Memory in Adulthood.

Jouroukhin, Yan · 2019

Astrocyte-specific expression of DN-DISC1 combined with adolescent THC synergistically impaired recognition memory in adult mice.

Effects of Fatty Acid Amide Hydrolase Inhibitors Acute Administration on the Positive and Cognitive Symptoms of Schizophrenia in Mice.

Kruk-Slomka, Marta · 2019

URB 597 (FAAH inhibitor) at 0.3 mg/kg attenuated MK-801-induced memory impairment, but at 1 mg/kg it worsened it.

Paternal THC exposure in rats causes long-lasting neurobehavioral effects in the offspring.

Levin, Edward D · 2019

Paternal THC exposure (2 mg/kg/day for 12 days) did not affect litter size, sex ratio, birth weight, or survival, but caused significant, long-lasting impairment in attentional performance and increased habituation of locomotor activity in adult offspring..

Elevation of endocannabinoids in the brain by synthetic cannabinoid JWH-018: mechanism and effect on learning and memory.

Li, Ren-Shi · 2019

JWH-018 elevated anandamide and 2-AG levels in the hippocampus by suppressing the enzymes that break them down (FAAH and MAGL).

Acute effect of vaporized Cannabis on sleep and electrocortical activity.

Mondino, Alejandra · 2019

A single vaporized dose of Cannabis with THC 11.5% (and negligible other cannabinoids) was linked to a short-lived increase in NREM sleep (non-REM sleep, a deeper non-dream sleep stage), but only at the 200 mg dose and only during the first hour of the light phase.

Memory deficits induced by chronic cannabinoid exposure are prevented by adenosine A2AR receptor antagonism.

Mouro, Francisco M · 2019

Chronic istradefylline (3 mg/kg/28 days) reversed memory deficits (Novel Object Recognition Test) caused by chronic WIN 55,212-2 (1 mg/kg/28 days).

EXTENDED ATTENUATION OF CORTICOSTRIATAL POWER AND COHERENCE AFTER ACUTE EXPOSURE TO VAPOURIZED Δ9 TETRAHYDROCANNABINOL IN RATS.

Nelong, Tapia Foute · 2019

Vaporized THC suppressed gamma power (>32-100 Hz) in the dorsal striatum, orbitofrontal cortex, and prefrontal cortex of rats, with most changes still present a week after a single exposure..

Impact of Chronic Cannabis Use on Auditory Mismatch Negativity Generation in Schizophrenia Patients.

Roser, Patrik · 2019

Schizophrenia patients without cannabis use showed reduced frontocentral MMN to duration deviants compared to healthy controls, as expected.

Neural and behavioral correlates of attentional bias to cannabis cues among adults with cannabis use disorders.

Ruglass, Lesia M · 2019

Cannabis users had more difficulty ignoring cannabis distractors (selective attention failure), committed more errors when cannabis cues were present, and showed an augmented and earlier N1 ERP component (125-200 ms post-stimulus) to cannabis cues, indicating an involuntary early perceptual bias toward cannabis-related stimuli..

Beneficial and deleterious effects of cannabinoids in the brain: the case of ultra-low dose THC.

Sarne, Yosef · 2019

This review examined what happens when you give mice THC at doses so low they produce no detectable behavioral effects — 3 to 4 orders of magnitude below what it takes to get a mouse "high." The results were striking: these ultra-low doses protected against various types of brain injury, including carbon monoxide toxicity, MDMA-induced damage, and age-related cognitive decline. The proposed mechanism was preconditioning.

Cross-domain correlates of cannabis use disorder severity among young adults.

Schuster, Randi Melissa · 2019

Of 71 candidate variables, five predicted CUD severity: more frequent cannabis use in the past 90 days, greater expectations that cannabis causes cognitive/behavioral impairment, greater self-reported metacognitive deficits, greater anxiety, and lower reaction time variability on sustained attention (though this last variable was less robust)..

Cannabinoid CB1 and CB2 receptor mechanisms underlie cannabis reward and aversion in rats.

Spiller, Krista J · 2019

Using electrical brain stimulation in rats, researchers mapped out how THC affects the brain's reward system at different doses.

Feasibility and effects of galantamine on cognition in humans with cannabis use disorder.

Sugarman, Dawn E · 2019

Both the galantamine and placebo groups showed modest improvements in response inhibition and attention over 10 days.

Age of onset of cannabis use and decision making under uncertainty.

Alameda-Bailén, Jose Ramón · 2018

Researchers compared decision-making ability across three groups: 72 participants divided into early-onset cannabis users (who started before 18), late-onset users (who started at 18 or later), and non-using controls.

The Influence of DAT1, COMT, and BDNF Genetic Polymorphisms on Total and Subregional Hippocampal Volumes in Early Onset Heavy Cannabis Users.

Batalla, Albert · 2018

Researchers examined hippocampal brain structure in 59 young men aged 18-30, including 30 chronic cannabis users who started regular use before age 16 and 29 controls.

Attitudes, perceptions, and use of marijuana in youth with multiple sclerosis.

Brenton, J Nicholas · 2018

Researchers surveyed 52 consecutive pediatric-onset MS patients from three US centers about their marijuana use attitudes and habits.

Biphasic effects of THC in memory and cognition.

Calabrese, Edward J · 2018

The well-known cognitive impairment from THC — disrupted short-term memory, slower processing — turns out to be only half the story.

Cannabis Withdrawal in Adults With Attention-Deficit/Hyperactivity Disorder.

Chauchard, Emeline · 2018

Researchers studied 23 cannabis-dependent adults with ADHD who described their most serious quit attempt without formal treatment.

THC exposure of human iPSC neurons impacts genes associated with neuropsychiatric disorders.

Guennewig, Boris · 2018

Researchers exposed neurons derived from human induced pluripotent stem cells (hiPSCs) to THC and analyzed the effects on gene expression. Both acute and chronic THC exposure dampened the neurons' transcriptional response when stimulated with potassium chloride (which mimics neuronal activation).

The effects of synthetic cannabinoids (SCs) on brain structure and function.

Livny, A · 2018

Fifteen chronic synthetic cannabinoid (SC) users and 15 healthy controls underwent MRI scans while performing cognitive tasks. SC users showed reduced total gray matter volume compared to controls, along with reduced volume in specific regions: middle frontal gyrus, frontal orbital gyrus, inferior frontal gyrus, insula, anterior cingulate cortex, and precuneus. On a working memory task (N-back), SC users performed worse behaviorally and showed diminished brain activation in the precuneus, cuneus, lingual gyrus, hippocampus, and cerebellum. On a response inhibition task (Go-No-Go), no group differences were found in either performance or brain activation. This was the first study showing both overall and region-specific gray matter volume reductions in chronic SC users, and the first to demonstrate impaired neural mechanisms for working memory specifically..

Distress intolerance moderation of neurophysiological markers of response inhibition after induced stress: Relations with cannabis use disorder.

Macatee, Richard J · 2018

Researchers tested whether high distress intolerance (difficulty tolerating negative emotions) would lead to stress-induced impairment of response inhibition in frequent cannabis users. Cannabis users with high and low distress intolerance completed a Go/No-Go task during EEG recording before and after a laboratory stressor. Contrary to the hypothesis, cannabis users with high distress intolerance showed enhanced conflict-monitoring neural activity (N2 amplitude) after stress rather than impairment.

How Substance Users With ADHD Perceive the Relationship Between Substance Use and Emotional Functioning.

Mitchell, John T · 2018

Researchers analyzed narrative comments from 92 persistent and desistent substance users from the MTA (Multimodal Treatment Study of ADHD) adult follow-up (ages 21.7-26.7). Persistent substance users generally perceived that substance use positively affects emotional states and that positive emotional effects outweigh negative ones.

Marijuana and Its Effects on Athletic Performance: A Systematic Review.

Trinh, Kien V · 2018

Only three trials met inclusion criteria.

Understanding marijuana's effects on functional connectivity of the default mode network in patients with schizophrenia and co-occurring cannabis use disorder: A pilot investigation.

Whitfield-Gabrieli, Susan · 2018

At baseline, schizophrenia patients showed DMN hyperconnectivity (correlated with positive symptom severity) and reduced anticorrelation between the DMN and executive control network compared to controls.

Intra-accumbal blockade of endocannabinoid CB1 receptors impairs learning but not retention of conditioned relief.

Bergado Acosta, Jorge R · 2017

When the CB1 receptor blocker rimonabant was injected directly into the nucleus accumbens before conditioning, rats failed to learn relief associations.

Extract of Fructus Cannabis Ameliorates Learning and Memory Impairment Induced by D-Galactose in an Aging Rats Model.

Chen, Ning-Yuan · 2017

Rats given D-galactose to induce accelerated aging and memory impairment showed significant improvement when simultaneously treated with hemp seed extract (EFC).

Cannabinoids in attention-deficit/hyperactivity disorder: A randomised-controlled trial.

Cooper, Ruth E · 2017

In this pilot randomized, placebo-controlled trial, 30 adults with ADHD received either Sativex oromucosal spray (THC:CBD) or placebo.

The Grass Might Be Greener: Medical Marijuana Patients Exhibit Altered Brain Activity and Improved Executive Function after 3 Months of Treatment.

Gruber, Staci A · 2017

Medical marijuana patients were assessed before starting treatment and after 3 months using fMRI while performing the Multi-Source Interference Test (MSIT).

Disruption of hippocampal synaptic transmission and long-term potentiation by psychoactive synthetic cannabinoid 'Spice' compounds: comparison with Δ9 -tetrahydrocannabinol.

Hoffman, Alexander F · 2017

This study directly compared three widely abused synthetic cannabinoids from "Spice" products with THC in their ability to disrupt brain communication in the mouse hippocampus, a region critical for memory and learning. JWH-018 was the most potent, inhibiting synaptic transmission with an EC50 of approximately 15 nM, roughly 47 times more potent than THC (EC50 approximately 700 nM).

Repeated Acute Oral Exposure to Cannabis sativa Impaired Neurocognitive Behaviours and Cortico-hippocampal Architectonics in Wistar Rats.

Imam, A · 2017

Rats given oral cannabis extract (20 mg/kg) daily for seven consecutive days showed significant cognitive and neurological impairments compared to controls. In the Open Field Test, cannabis-treated rats showed reduced rearing (exploratory behavior) and increased freezing, indicating decreased curiosity and increased anxiety-like behavior.

Distinct effects of childhood ADHD and cannabis use on brain functional architecture in young adults.

Kelly, Clare · 2017

This neuroimaging study examined 75 young adults (ages 21-25) followed since childhood as part of the landmark MTA study of ADHD, comparing brain functional connectivity across four groups: ADHD with cannabis use, ADHD without cannabis, non-ADHD with cannabis, and non-ADHD without cannabis. Childhood ADHD was associated with weakened connectivity in brain networks supporting executive function and motor control, consistent with known ADHD features. Contrary to expectations, the effects of cannabis use were distinct from those of ADHD, affecting different brain networks.

Inspired by Mary Jane? Mechanisms underlying enhanced creativity in cannabis users.

LaFrance, Emily M · 2017

This study tested 412 sober cannabis users and 309 non-users on both self-reported and objective creativity measures to determine whether cannabis use is associated with enhanced creativity. At first glance, the results supported the creative cannabis user stereotype.

Effects of Extended Cannabis Abstinence on Cognitive Outcomes in Cannabis Dependent Patients with Schizophrenia vs Non-Psychiatric Controls.

Rabin, Rachel A · 2017

Nineteen cannabis-dependent patients with schizophrenia and 20 cannabis-dependent controls without psychiatric illness attempted 28 days of cannabis abstinence.

Selective post-training time window for memory consolidation interference of cannabidiol into the prefrontal cortex: Reduced dopaminergic modulation and immediate gene expression in limbic circuits.

Rossignoli, Matheus Teixeira · 2017

Researchers tested whether CBD delivered directly to the prefrontal cortex could interfere with the consolidation of fear memories in rats.

CB1 Cannabinoid Receptors Mediate Cognitive Deficits and Structural Plasticity Changes During Nicotine Withdrawal.

Saravia, Rocio · 2017

Researchers discovered that the cognitive deficits occurring during nicotine withdrawal are mediated by the endocannabinoid system, specifically through CB1 receptors on inhibitory (GABAergic) neurons. During nicotine withdrawal in mice, 2-AG levels (but not anandamide) increased.

Cannabidiol disrupts the consolidation of specific and generalized fear memories via dorsal hippocampus CB1 and CB2 receptors.

Stern, Cristina A J · 2017

Researchers induced different intensities of fear memories in rats using varying shock levels, creating either specific fear (responding only to the original context) or generalized fear (responding fearfully to new, similar contexts). CBD (3-30 mg/kg) given immediately after fear acquisition disrupted consolidation of both types.

Emotion regulation deficits in regular marijuana users.

Zimmermann, Kaeli · 2017

Researchers compared 23 regular marijuana users to 20 non-using controls using brain imaging during an emotion regulation task.

Cannabinoids reverse the effects of early stress on neurocognitive performance in adulthood.

Alteba, Shirley · 2016

Researchers tested whether cannabinoid treatment during late adolescence could reverse the long-term cognitive damage caused by early life stress in rats. Male and female rats were stressed during their first two weeks of life, then treated with the cannabinoid agonist WIN55,212-2 for two weeks during late adolescence.

Synthetic cannabinoid JWH-018 and its halogenated derivatives JWH-018-Cl and JWH-018-Br impair Novel Object Recognition in mice: Behavioral, electrophysiological and neurochemical evidence.

Barbieri, M · 2016

Researchers compared the cognitive effects of three synthetic cannabinoids (JWH-018, JWH-018-Cl, and JWH-018-Br) with THC in mice using a novel object recognition test. All three synthetic compounds dose-dependently impaired both short-term (2-hour) and long-term (24-hour) memory retention, and they were more potent than THC at producing these deficits. In hippocampal brain slice experiments, the synthetic compounds also disrupted electrically evoked synaptic transmission, long-term potentiation (LTP, a cellular mechanism of memory), and the release of both glutamate and GABA.

Attention deficit hyperactivity disorder and drug addiction rehabilitation patients.

Camargo, Carlos Henrique Ferreira · 2016

Researchers evaluated 80 adult patients in therapeutic communities (drug rehabilitation) for ADHD and substance use patterns. While the overall prevalence of drug use did not differ between ADHD and non-ADHD patients, important pattern differences emerged.

Dorsal hippocampal NMDA receptors mediate the interactive effects of arachidonylcyclopropylamide and MDMA/ecstasy on memory retrieval in rats.

Ghaderi, Marzieh · 2016

Both cannabinoids and MDMA (ecstasy) can impair memory individually, but this study found something unexpected: when given together, MDMA actually reversed the memory problems caused by a synthetic cannabinoid. The researchers injected the synthetic cannabinoid ACPA directly into the hippocampus of rats, which impaired their ability to remember a passive avoidance task.

Variable activation in striatal subregions across components of a social influence task in young adult cannabis users.

Gilman, Jodi M · 2016

Twenty young adult cannabis users and 20 non-users completed a decision-making task while undergoing brain scans.

Neural mechanisms of sensitivity to peer information in young adult cannabis users.

Gilman, Jodi M · 2016

This companion study to RTHC-01164 used a slightly different social influence paradigm with 20 cannabis-using young adults and 23 controls.

Comparisons of Δ9-Tetrahydrocannabinol and Anandamide on a Battery of Cognition-Related Behavior in Nonhuman Primates.

Kangas, Brian D · 2016

Using touchscreen cognitive tests in squirrel monkeys, researchers compared THC with anandamide (the brain's own cannabinoid) and drugs that boost anandamide levels. THC produced clear, dose-related impairments across multiple cognitive domains.

Long-term hippocampal glutamate synapse and astrocyte dysfunctions underlying the altered phenotype induced by adolescent THC treatment in male rats.

Zamberletti, Erica · 2016

Male rats that received THC during adolescence showed lasting cognitive deficits and psychotic-like behaviors in adulthood, but no emotional disturbances.

Effects of the cannabinoid 1 receptor peptide ligands hemopressin, (m)RVD-hemopressin(α) and (m)VD-hemopressin(α) on memory in novel object and object location recognition tasks in normal young and Aβ1-42-treated mice.

Zhang, Rui-San · 2016

Hemopressin (Hp), a natural peptide that blocks the CB1 cannabinoid receptor, improved memory formation and extended how long mice retained memories in object recognition tasks.

Adolescent cannabis exposure interacts with mutant DISC1 to produce impaired adult emotional memory.

Ballinger, Michael D · 2015

Researchers studied mice carrying a mutation in the DISC1 gene (disrupted in schizophrenia 1) to test whether adolescent THC exposure interacts with genetic vulnerability to worsen adult brain function.

An fMRI-Based Neural Signature of Decisions to Smoke Cannabis.

Bedi, Gillinder · 2015

Researchers combined brain imaging with a real-world-like purchasing task where daily cannabis smokers made repeated decisions to buy or decline puffs of cannabis at various prices.

Abstinence phenomena of chronic cannabis-addicts prospectively monitored during controlled inpatient detoxification (Part II): Psychiatric complaints and their relation to delta-9-tetrahydrocannabinol and its metabolites in serum.

Bonnet, Udo · 2015

Thirty-five chronic cannabis-dependent individuals were monitored during inpatient detoxification using both clinician-rated and self-reported psychiatric scales.

Cannabidiol increases survival and promotes rescue of cognitive function in a murine model of cerebral malaria.

Campos, A C · 2015

Researchers infected mice with a malaria parasite that causes cerebral malaria and treated them with CBD (30mg/kg/day).

Impaired learning from errors in cannabis users: Dorsal anterior cingulate cortex and hippocampus hypoactivity.

Carey, Susan E · 2015

Fifteen chronic cannabis users and 15 controls completed a paired-associate learning task during brain scanning.

Neuropsychological sex differences associated with age of initiated use among young adult cannabis users.

Crane, Natania A · 2015

Researchers examined 44 male and 25 female young adult cannabis users to determine whether the age of first cannabis use affected cognitive function differently by sex.

What to make of cannabis and cognition in MS: In search of clarity amidst the haze.

Feinstein, Anthony · 2015

This review examined the sparse literature on cannabis effects on cognition in people with multiple sclerosis.

Combined effects of marijuana and nicotine on memory performance and hippocampal volume.

Filbey, Francesca M · 2015

Researchers compared hippocampal brain volumes and memory performance across four groups: marijuana-only users (n=36), nicotine-only users (n=19), combined marijuana+nicotine users (n=19), and non-using controls (n=16). Marijuana and combined marijuana+nicotine groups had smaller total hippocampal volumes compared to nicotine-only and control groups.

Alcohol, cigarette, and illegal substance consumption among medical students: a cross-sectional survey.

Gignon, M · 2015

A survey of 255 randomly selected French medical students found substantial rates of substance use.

Cannabis and Exercise Science: A Commentary on Existing Studies and Suggestions for Future Directions.

Gillman, Arielle S · 2015

This commentary highlighted a major gap in the scientific literature: the relationship between recreational cannabis use and exercise is essentially unexamined.

An exploratory study of the combined effects of orally administered methylphenidate and delta-9-tetrahydrocannabinol (THC) on cardiovascular function, subjective effects, and performance in healthy adults.

Kollins, Scott H · 2015

In a double-blind crossover experiment, 16 healthy adults received all combinations of placebo or 10mg THC with 0mg, 10mg, or 40mg methylphenidate (MPH) across six sessions. The two drugs showed additive effects on heart rate: peak heart rate climbed from 89 beats per minute with THC alone to 96 with low-dose MPH added and 102 with high-dose MPH.

Dose-dependent effects of cannabis on the neural correlates of error monitoring in frequent cannabis users.

Kowal, Mikael A · 2015

Researchers used EEG to measure two brain signals related to error monitoring in frequent cannabis users: the error-related negativity (ERN), which reflects automatic error detection, and the error positivity (Pe), which reflects conscious error awareness. Participants who received a high dose (22mg THC) showed significantly reduced ERN compared to placebo, meaning their brains were less effective at automatically detecting mistakes.

Cannabis and creativity: highly potent cannabis impairs divergent thinking in regular cannabis users.

Kowal, Mikael A · 2015

Researchers tested whether cannabis enhances creativity by giving regular users either placebo, low-dose (5.5mg THC), or high-dose (22mg THC) vaporized cannabis, then measuring their performance on creativity tasks. Participants who received the high dose performed significantly worse on the Alternate Uses Task, a measure of divergent thinking (the ability to generate multiple creative solutions).

Cortical thinness and volume differences associated with marijuana abuse in emerging adults.

Mashhoon, Y · 2015

Researchers compared brain structure in 15 cannabis users and 15 non-users (average age ~22) using high-resolution MRI.

Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects.

Smith, Matthew J · 2015

Researchers compared hippocampal shape in four groups: healthy controls (n=44), healthy controls with past cannabis use disorder (n=10), schizophrenia without substance history (n=28), and schizophrenia with past cannabis use disorder (n=15). Both cannabis-using groups showed distinct hippocampal shape differences from their respective non-using counterparts, but the patterns differed.

Balanced modulation of striatal activation from D2 /D3 receptors in caudate and ventral striatum: Disruption in cannabis abusers.

Tomasi, Dardo · 2015

Researchers used both fMRI and PET imaging to examine how dopamine D2/D3 receptors in two parts of the striatum modulate brain activity during a reaction-time task. In healthy controls, dopamine receptors in the caudate (dorsal striatum) and ventral striatum showed a balanced push-pull pattern: caudate receptors inhibited ventral striatum activity while ventral striatum receptors facilitated it.

Chronic exposure to WIN55,212-2 affects more potently spatial learning and memory in adolescents than in adult rats via a negative action on dorsal hippocampal neurogenesis.

Abboussi, Oualid · 2014

Researchers administered the synthetic cannabinoid WIN55,212-2 to adolescent rats (starting at postnatal day 27-30) and adult rats (starting at postnatal day 54-57) for 20 consecutive days, followed by a 20-day drug-free washout period.

The link between dopamine function and apathy in cannabis users: an [18F]-DOPA PET imaging study.

Bloomfield, Michael A P · 2014

Every participant scored above the clinical cutoff for apathy on the Apathy Evaluation Scale.

Investigation of sex-dependent effects of cannabis in daily cannabis smokers

Cooper, Ziva D. · 2014

Women gave higher "Good" (p<=0.05) and "Take Again" (p<=0.05) ratings than men under active cannabis conditions in a pooled analysis of four double-blind studies, despite no sex differences in intoxication ratings ("High," "Stimulated") or cardiovascular response.

Predicting creativity: the role of psychometric schizotypy and cannabis use in divergent thinking.

Minor, Kyle S · 2014

Divergent thinking (a measure of creativity) was greater in the positive schizotypy group compared to negative schizotypy and non-schizotypy groups, with small to medium effect sizes.

Pharmacological activation of CB1 receptor modulates long term potentiation by interfering with protein synthesis.

Navakkode, Sheeja · 2014

Pre-treating rat hippocampal brain slices with the CB1 receptor agonist WIN55,212-2 significantly impaired long-term potentiation (LTP), a cellular mechanism believed to underlie learning and memory.

Delta-9-tetrahydrocannabinol disrupts hippocampal neuroplasticity and neurogenesis in trained, but not untrained adolescent Sprague-Dawley rats.

Steel, Ryan W J · 2014

When adolescent rats were trained on a spatial learning task while receiving daily THC (6 mg/kg), two key findings emerged.

St8sia2 deficiency plus juvenile cannabis exposure in mice synergistically affect higher cognition in adulthood.

Tantra, Martesa · 2014

Juvenile THC treatment (7 mg/kg every other day for 3 weeks) had no appreciable effect on cognition in normal (wildtype) mice.

Functional imaging of implicit marijuana associations during performance on an Implicit Association Test (IAT).

Ames, Susan L · 2013

Thirteen heavy cannabis users and 15 non-using controls (ages 18-25) completed a marijuana Implicit Association Test during fMRI.

Cannabis abuse is associated with better emotional memory in schizophrenia: a functional magnetic resonance imaging study.

Bourque, Josiane · 2013

Researchers compared emotional memory and brain activation in three groups: 14 schizophrenia patients with cannabis abuse (dual-diagnosis, DD), 14 non-using schizophrenia patients (SCZ), and 21 healthy controls (HC).

Neural mechanisms of risky decision-making and reward response in adolescent onset cannabis use disorder.

De Bellis, Michael D · 2013

Three groups of male adolescents were compared during a decision-making fMRI task: 15 with cannabis use disorder in remission, 23 controls with other psychiatric conditions, and 18 healthy controls.

Marijuana use is associated with inattention in men and sleep quality in women with Attention-Deficit/Hyperactivity Disorder: a preliminary study.

Ly, Christine · 2013

Fifty-six men and 20 women with ADHD (ages 18-45) were assessed for marijuana use, ADHD symptoms, and sleep quality.

Chronic co-administration of the cannabinoid receptor agonist WIN55,212-2 during puberty or adulthood reverses 3,4 methylenedioxymetamphetamine (MDMA)-induced deficits in recognition memory but not in effort-based decision making.

Schulz, Sybille · 2013

Rats received MDMA, the cannabinoid agonist WIN55,212-2, both, or vehicle for 25 days during either puberty (PD40-65) or adulthood (PD80-105).

A preliminary study of functional brain activation among marijuana users during performance of a virtual water maze task.

Sneider, Jennifer Tropp · 2013

Ten chronic marijuana users and 18 non-using controls performed a virtual version of the Morris water maze (a classic spatial memory test) during fMRI scanning.

Short- and long-term cognitive effects of chronic cannabinoids administration in late-adolescence rats.

Abush, Hila · 2012

Rats received the cannabinoid agonist WIN55,212-2 daily during late adolescence and were tested at multiple timepoints.

An fMRI Study of Neuronal Activation in Schizophrenia Patients with and without Previous Cannabis Use.

Løberg, Else-Marie · 2012

Twenty-six schizophrenia patients were divided into previous cannabis users and never-users and compared during an auditory attention task (dichotic listening) using fMRI.

Combined effects of THC and caffeine on working memory in rats.

Panlilio, Leigh V · 2012

Researchers tested THC and caffeine combinations in rats performing a working memory task.

Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the 'runner's high'

Raichlen, David A. · 2012

Circulating endocannabinoid levels rose after high-intensity endurance running in humans and in dogs.

Alterations of theory of mind network activation in chronic cannabis users.

Roser, Patrik · 2012

Fifteen chronic cannabis users and 14 controls underwent brain imaging while performing a theory of mind task (interpreting cartoon stories that required understanding characters' intentions).

Investigating the interaction between schizotypy, divergent thinking and cannabis use.

Schafer, Gráinne · 2012

Researchers tested 160 cannabis users on two separate days: once sober and once intoxicated.

Examining the effects of former cannabis use on cerebellum-dependent eyeblink conditioning in humans.

Steinmetz, Adam B · 2012

Researchers compared three groups of 10 participants each on an eyeblink conditioning task that depends on the cerebellum.

The CB(1) receptor antagonist, AM281, improves recognition loss induced by naloxone in morphine withdrawal mice.

Vaseghi, Golnaz · 2012

Mice made dependent on morphine showed significant memory impairment during naloxone-precipitated withdrawal, measured by an object recognition task.

Delay- and dose-dependent effects of Δ⁹-tetrahydrocannabinol administration on spatial and object working memory tasks in adolescent rhesus monkeys.

Verrico, Christopher D · 2012

Adolescent rhesus monkeys received a range of THC doses (30-240 mcg/kg) intravenously while performing spatial and object working memory tasks.

Medial temporal structures and memory functions in adolescents with heavy cannabis use.

Ashtari, Manzar · 2011

Researchers compared hippocampal brain structure between 14 heavy cannabis-using adolescents (averaging 5.8 joints per day) and 14 matched controls using high-resolution MRI, after an average of 6.7 months of supervised abstinence. Heavy cannabis users had significantly smaller right (p < 0.04) and left (p < 0.02) hippocampal volumes compared to controls.

Effects of chronic, heavy cannabis use on executive functions.

Crean, Rebecca D · 2011

The case described a cannabis-dependent person entering a 12-week abstinence-based research program.

Altered brain activation during visuomotor integration in chronic active cannabis users: relationship to cortisol levels.

King, George R · 2011

Thirty cannabis users (16 men, 14 women) and 30 matched controls were tested with neuropsychological assessments and fMRI during a finger-sequencing task. Male, but not female, cannabis users had significantly slower psychomotor speed.

Benign and time-limited visual disturbances (flashbacks) in recent abstinent high-potency heavy cannabis smokers: a case series study.

Lerner, Arturo G · 2011

Eight patients seeking outpatient detoxification for cannabis dependence reported visual disturbances both during intoxication and persisting after they stopped using cannabis.

MDMA & cannabis: a mini-review of cognitive, behavioral, and neurobiological effects of co-consumption.

Schulz, Sybille · 2011

This review examined 23 articles on the combined effects of MDMA (ecstasy) and cannabis.

Acute effects of delta-9-tetrahydrocannabinol on performance monitoring in healthy volunteers.

Spronk, Desirée · 2011

Ten healthy volunteers completed a speeded Flankers task (a test of accuracy under time pressure) after receiving THC or placebo vapor in a double-blind crossover design.

Association between a cannabinoid receptor gene (CNR1) polymorphism and cannabinoid-induced alterations of the auditory event-related P300 potential.

Stadelmann, Andreas M · 2011

Twenty healthy volunteers received oral THC, cannabis extract (THC + CBD), or placebo in a controlled study.

Sleep disturbance and the effects of extended-release zolpidem during cannabis withdrawal.

Vandrey, Ryan · 2011

When participants stopped cannabis for three nights and took placebo at bedtime, objective sleep quality dropped.

delta(9)-Tetrahydrocannabinol-dependent mice undergoing withdrawal display impaired spatial memory.

Wise, Laura E · 2011

Rats received the cannabinoid agonist WIN55,212-2 daily during late adolescence (postnatal days 45-60) and were tested at 24 hours, 10 days, 30 days, and 75 days after the last injection.

Functional MRI evidence for inefficient attentional control in adolescent chronic cannabis abuse.

Abdullaev, Yalchin · 2010

Fourteen young adults with chronic adolescent cannabis use were compared to 14 matched non-users on two attention tasks during fMRI scanning. On the Attention Network Task, cannabis users performed worse (slower reaction times and more errors) specifically on trials requiring executive attention (processing conflicting information).

Altered parahippocampal functioning in cannabis users is related to the frequency of use.

Becker, Benjamin · 2010

Forty-two cannabis users underwent fMRI while encoding and retrieving face-profession associations.

The impact of early-onset cannabis use on functional brain correlates of working memory.

Becker, Benjamin · 2010

Twenty-six early-onset cannabis users (first use before age 16) and 17 late-onset users (first use at 16 or later) were compared on a verbal working memory task during fMRI. Early-onset users showed significantly increased activation in the left superior parietal lobe during the task.

Longitudinal study of cognition among adolescent marijuana users over three weeks of abstinence.

Hanson, Karen L · 2010

Nineteen adolescent marijuana users (ages 15-19) and 21 non-using controls were tested at three time points: after 3 days, 2 weeks, and 3 weeks of confirmed abstinence. Marijuana users performed significantly worse on verbal learning (p<0.01), verbal working memory (p<0.05), and attention accuracy (p<0.01) compared to controls. Verbal learning improved after 2 weeks of abstinence, and working memory improved after 3 weeks, suggesting these deficits can recover. However, attention accuracy remained impaired throughout the entire 3-week abstinence period, suggesting more persistent effects on prefrontal cortex function. Abstinence was verified through decreasing THC metabolite levels on serial urine drug screens..

Learning and memory performances in adolescent users of alcohol and marijuana: interactive effects.

Mahmood, Omar M · 2010

Researchers tested memory and learning in 130 adolescents aged 15 to 19.

A cannabinoid CB(1) receptor antagonist ameliorates impairment of recognition memory on withdrawal from MDMA (Ecstasy).

Nawata, Yoko · 2010

Mice received MDMA (ecstasy) daily for 7 days.

Processing dynamic facial affect in frequent cannabis-users: evidence of deficits in the speed of identifying emotional expressions.

Platt, Bradley · 2010

Researchers compared emotion recognition between heavy cannabis users and non-using controls using dynamic facial expressions that gradually changed from neutral to increasingly intense emotional displays. Cannabis users were significantly slower at identifying all three emotional expressions (sadness, anger, and happiness).

Evidence of increased activation underlying cognitive control in ecstasy and cannabis users.

Roberts, Gloria M P · 2010

Twenty recreational drug users (predominantly ecstasy and cannabis) and 20 healthy controls completed a GO/NOGO impulse control task during fMRI scanning. Despite no differences in behavioral performance (both groups performed equally), drug users showed significantly elevated brain activation in frontal and parietal regions during successful response inhibition.

A comparison of psychosocial and cognitive functioning between depressed and non-depressed patients with cannabis dependence.

Secora, Alex M · 2010

Researchers compared 54 cannabis-dependent individuals with comorbid depression to 54 with cannabis dependence alone. As expected, the depressed group showed significantly more psychosocial impairment on the Addiction Severity Index, with greater difficulties in social and daily functioning. However, contrary to the hypothesis that depression would compound cognitive deficits, the depressed group actually performed better on some computerized cognitive assessment modules.

Modulation of mediotemporal and ventrostriatal function in humans by Delta9-tetrahydrocannabinol: a neural basis for the effects of Cannabis sativa on learning and psychosis.

Bhattacharyya, Sagnik · 2009

In a double-blind crossover study, 15 healthy men received 10 mg THC, 600 mg CBD, or placebo before completing a verbal learning task during fMRI scanning. THC increased psychotic symptoms and anxiety while disrupting normal brain activation patterns.

Impaired error awareness and anterior cingulate cortex hypoactivity in chronic cannabis users.

Hester, Robert · 2009

Sixteen active chronic cannabis users and 16 controls performed a Go/No-go response inhibition task during fMRI scanning.

Functional consequences of marijuana use in adolescents

Jacobus, Joanna · 2009

Across the studies reviewed, adolescents who used marijuana heavily tended to score lower on attention, learning, and processing speed.

Learning and memory deficits in ecstasy users and their neural correlates during a face-learning task.

Roberts, Gloria M P · 2009

Twenty recreational ecstasy users, 14 cannabis users, and 20 controls completed a face-learning task during fMRI scanning. Ecstasy users performed significantly worse at learning and remembering face-name associations compared to both controls and cannabis users. Brain imaging revealed ecstasy-specific patterns: hyperactivity in bilateral frontal, temporal, parietal, and occipital regions, and hypoactivity in the right dorsal anterior cingulate cortex and left posterior cingulate. Some brain activation changes overlapped between ecstasy and cannabis groups: both showed decreased activation in the right medial frontal gyrus, left parahippocampal gyrus, left dorsal cingulate, and left caudate. These results identified both ecstasy-specific and shared ecstasy-cannabis neural effects, with the ecstasy-specific effects potentially related to neurotoxic damage to serotonergic brain regions..

Corpus callosum damage in heavy marijuana use: preliminary evidence from diffusion tensor tractography and tract-based spatial statistics.

Arnone, D · 2008

Using diffusion tensor imaging (DTI), researchers compared the corpus callosum (the major white matter tract connecting the brain's left and right hemispheres) in 11 heavy marijuana users who started in early adolescence and 11 age-matched controls. Mean diffusivity (MD), a measure of structural integrity, was significantly increased in marijuana users in the region of the corpus callosum where fibers pass between the prefrontal lobes.

Delta9-Tetrahydrocannabinol-induced cognitive deficits are reversed by olanzapine but not haloperidol in rats.

Egashira, Nobuaki · 2008

Researchers tested whether two different antipsychotic medications could reverse the spatial memory impairment caused by THC in rats using an eight-arm radial maze. THC (6 mg/kg) impaired spatial memory and decreased acetylcholine (ACh) levels in the dorsal hippocampus, a brain region critical for spatial memory. Olanzapine (0.1 mg/kg), an atypical antipsychotic, reversed both the memory deficit and the acetylcholine decrease caused by THC.

Functional correlates of verbal memory deficits emerging during nicotine withdrawal in abstinent adolescent cannabis users.

Jacobsen, Leslie K · 2007

Researchers compared 20 adolescent cannabis-and-tobacco users with 25 tobacco-only users.

High suicide risk after the development of cognitive and working memory deficits caused by cannabis, cocaine and ecstasy use.

Pompili, Maurizio · 2007

The authors described a 30-year-old man who used cannabis, MDMA (ecstasy), and cocaine for at least three years and subsequently developed significant cognitive and working memory deficits. These cognitive problems led to increasing difficulties in his professional and personal life.

Scopolamine and MK801-induced working memory deficits in rats are not reversed by CBD-rich cannabis extracts.

Fadda, Paola · 2006

Previous research had shown that CBD-rich cannabis extracts could reverse working memory deficits caused by THC in a dose-dependent manner.

The effects of concurrent cannabis use among ecstasy users: neuroprotective or neurotoxic?

Fisk, John E · 2006

Researchers reanalyzed data from multiple studies to test whether using cannabis alongside ecstasy (MDMA) might protect against ecstasy-related cognitive damage, based on evidence that cannabinoids can be neuroprotective under certain conditions. They compared three groups: people who typically use cannabis and ecstasy at the same time, people who use ecstasy without concurrent cannabis, and non-ecstasy users.

Long-term effects of frequent cannabis use on working memory and attention: an fMRI study.

Jager, Gerry · 2006

Researchers used fMRI to compare 10 frequent cannabis users (after one week of abstinence) with 10 non-using controls matched for age, gender, and estimated IQ.

Neural substrates of faulty decision-making in abstinent marijuana users.

Bolla, Karen I · 2005

Researchers used PET imaging during the Iowa Gambling Task to study decision-making in 11 heavy marijuana users after 25 days of supervised abstinence at an NIH inpatient unit, compared to 11 non-drug users. The marijuana group showed greater activation in the left cerebellum and less activation in the right lateral orbitofrontal cortex and right dorsolateral prefrontal cortex compared to controls. When the marijuana group was split by usage level, heavy users (53-84 joints/week) showed less activation in the left medial orbitofrontal cortex and greater cerebellar activation than moderate users (8-35 joints/week).

Neuroimaging of marijuana smokers during inhibitory processing: a pilot investigation.

Gruber, Staci A · 2005

Researchers used fMRI and diffusion tensor imaging (DTI) to study heavy cannabis smokers and matched controls during a Stroop task, which measures impulse control and interference processing. Cannabis smokers showed significantly lower anterior cingulate cortex activity and higher midcingulate activity compared to controls.

Recent cannabis abuse decreased stress-induced BOLD signals in the frontal and cingulate cortices of cocaine dependent individuals.

Li, Chiang-Shan Ray · 2005

Researchers used fMRI to compare stress-induced brain activation in two groups of abstinent cocaine-dependent individuals: eight who had recently also abused cannabis and 18 who had not.

Auditory-evoked potentials and selective attention: different ways of information processing in cannabis users and controls.

Kempel, P · 2003

Using event-related potentials during a complex auditory attention task, the study found that controls showed shorter latencies for negative brain wave peaks (at 200 and 300 ms) to target tones compared to non-targets, while cannabis users showed no clear difference between targets and non-targets.

Reduced binocular depth inversion in regular cannabis users.

Semple, David M · 2003

Ten regular cannabis users showed significantly higher scores on the binocular depth inversion illusion (BDII) for inverted images compared to 10 matched controls.

Effects of chronic Delta(9)-tetrahydrocannabinol treatment on hippocampal extracellular acetylcholine concentration and alternation performance in the T-maze.

Nava, F · 2001

Rats given chronic THC treatment (5 mg/kg twice daily for two weeks) continued to show reduced hippocampal acetylcholine levels and impaired T-maze performance without developing tolerance to either effect.

Cognitive performance amongst recreational users of "ecstasy".

Rodgers, J · 2000

Researchers compared cognitive function across three groups of 15 young people: regular ecstasy users, regular cannabis users who had never taken ecstasy, and drug-free controls. Reaction times (visual, auditory, complex) were similar across all three groups.

Comparative effects of alcohol and marijuana on mood, memory, and performance.

Heishman, S J · 1997

Five male volunteers received three doses each of alcohol and marijuana under double-blind conditions across seven sessions, using technology that controlled puffing and inhalation parameters for precise marijuana dosing. At the highest doses, perceived impairment was identical for alcohol and marijuana.

Effects of long-term cannabis use on selective attention: an event-related potential study.

Solowij, N · 1991

Researchers recorded brain event-related potentials (ERPs) from nine long-term cannabis users and nine non-user controls during a complex listening task.

Effects of marihuana-dextroamphetamine combination.

Evans, M A · 1976

In two double-blind, randomized studies, researchers tested the combination of marijuana and dextroamphetamine.

Alcohol and marijuana effects on ocular tracking.

Flom, M C · 1976

Researchers tested experienced substance users on a visual tracking task where participants followed a small moving dot with their eyes.

The combined effect of marihuana and dextroamphetamine.

Forney, R · 1976

In mice, THC enhanced locomotor activity and amplified the stimulant effects of methamphetamine.

Intact humoral and cell-mediated immunity in chronic marijuana smoking.

Rachelefsky, G S · 1976

Twelve healthy adults smoked cannabis daily for 64 consecutive days in a controlled hospital setting while researchers tracked multiple immune markers. B-cell counts, initially lower than controls, increased to normal levels over the study period.

Cannabis intoxication: effects of monetary incentive on performance, a controlled investigation of behavioural tolerance in moderate users of cannabis.

Casswell, S · 1975

Cannabis produced dose-related impairment on four out of five tasks testing short-term memory, goal-directed behavior, and reaction times.

Cannabis and Cognitive Function in Multiple Sclerosis: Findings From a Large Consecutive Clinical Sample.

Kever, Anne · 2025

Cannabis users (n = 254) performed significantly worse than nonusers (n = 593) on the Symbol Digit Modalities Test (processing speed, p = 0.014).

Patterns, Efficacy, and Cognitive Effects of Medical Cannabis Use in Chronic Musculoskeletal Pain Patients.

Khak, Mohammad · 2025

In a prospective survey of 129 long-term medical cannabis users with chronic musculoskeletal pain, 93.8% agreed or strongly agreed that cannabis improved their primary symptoms.

Neurometabolite Alterations Associated With Cannabis Use: A Proton Magnetic Resonance Spectroscopy Meta-Analysis.

Kirkland, Anna E · 2025

Compared to controls, cannabis users showed lower GABA and N-acetylaspartate (a marker of neural health) in the anterior cingulate cortex, lower glutamate in the basal ganglia/striatum, and lower glutamine and myo-inositol in the thalamus.

Delineating the molecular mechanisms of hippocampal neurotoxicity induced by chronic administration of synthetic cannabinoid AB-FUBINACA in mice.

Alzu'bi, Ayman · 2024

AB-FUBINACA caused significant recognition memory impairment along with hippocampal histopathological changes.

Association Between Cannabis Use and Subjective Cognitive Decline: Findings from the Behavioral Risk Factor Surveillance System (BRFSS).

Chen, Zhi · 2024

Non-medical cannabis use was associated with 96% decreased odds of subjective cognitive decline (aOR=0.04, 95% CI: 0.01-0.44, p<.01).

Cannabis use and cognitive biases in people with first-episode psychosis and their siblings.

Roldan, L · 2024

Daily and occasional cannabis use were associated with lower odds of speech illusions (OR = 0.605 and 0.646) and jumping to conclusions bias (OR = 0.625 and 0.602) compared to never-use.

Substance Use and College Completion Among Two-Year and Four-Year College Students From a Nationally Representative Longitudinal Study.

Rosenbaum, Janet E · 2024

Among propensity-matched four-year college students, past-year marijuana use was associated with lower completion (IRR = 1.30, p = 0.007), with stronger effects for frequent use (>=5 times/month, IRR = 1.44).

Cannabis Use Characteristics Associated with Self-Reported Cognitive Function in a Nationally Representative U.S. sample.

Rubin-Kahana, Dafna Sara · 2024

Current users (N = 3,681) and former users (N = 7,448) reported poorer cognition than never users (N = 24,956) on the Executive Function Index scales.

Attention Deficit Hyperactivity Disorder, Cannabis Use, and the Endocannabinoid System: A Scoping Review.

Ryan, Jennie E · 2024

The review identifies neurobiological overlap between endocannabinoid function and cognitive dysfunction seen in ADHD.

Neurocognitive Impact of Exposure to Cannabis Concentrates and Cannabinoids Including Vaping in Children and Adolescents: A Systematic Review.

Saavedra, Michell S · 2024

Across 19 included studies, cannabis exposure in youth was linked to a spectrum of CNS effects: transient mood alterations, lasting changes in cognitive function, and permanent sensory processing changes.

The Effects of Cannabidiol and δ-9-Tetrahydrocannabinol in Social Cognition: A Naturalistic Controlled Study.

Sainz-Cort, Alberto · 2024

Participants under THC showed lower cognitive empathy compared to CBD (but not compared to placebo).

A Latent Variable Analysis of Psychomotor and Neurocognitive Performance After Acute Cannabis Smoking.

Smith, Shelby J · 2023

Factor analysis identified a single latent construct underlying reaction time, decision making, working memory, and spatial-motor performance.

Prenatal cannabinoid exposure and early language development.

Talavera-Barber, Maria M · 2023

Late-exposed infants (2nd/3rd trimester) scored significantly higher on expressive and receptive language subscales at 12 months compared to unexposed infants.

Altered glial expression of the cannabinoid 1 receptor in the subiculum of a mouse model of Alzheimer's disease.

Terradillos, Itziar · 2023

CB1 receptor expression increased in reactive microglia surrounding amyloid plaques in the subiculum of 5xFAD mice.

Prenatal cannabis use and its impact on offspring neuro-behavioural outcomes: A systematic review.

Thompson, Mary · 2023

Meta-analyses showed no significant associations between prenatal cannabis exposure and attention, global IQ, reading, written comprehension, spelling, or mathematics.

A neuropsychological approach to differentiating cannabis-induced and primary psychotic disorders.

Woolridge, Stephanie M · 2023

Cannabis-induced psychosis and primary psychotic disorders may show different neuropsychological profiles despite similar clinical presentations.