Cannabis Impairs Attention While Nicotine Enhances It, But Both Harm Developing Brains

A comprehensive review found that cannabis/THC generally impairs multiple aspects of attention in adults, while nicotine tends to enhance it, but prenatal exposure to either substance is linked to attention deficits and behavioral disorders in offspring.

Oleszak, Kennedy et al.·Current topics in behavioral neurosciences·2025·Moderate EvidenceNarrative Review
RTHC-07277Narrative ReviewModerate Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Narrative Review
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Cannabis impairs selective attention and creates attentional bias toward cannabis cues. Reaction time effects depend on timing of last exposure. Preclinical studies show cannabis-induced attention deficits persist after abstinence. Nicotine has dose-dependent effects on attention. Prenatal exposure to either substance increases risk for ADHD, attention deficits, and impulsivity in offspring.

Key Numbers

Review covers preclinical and clinical studies across all developmental periods; prenatal cannabis exposure linked to increased ADHD, schizophrenia, and drug-seeking risk in offspring; prenatal nicotine exposure shows sex differences with males more affected.

How They Did This

Narrative review synthesizing preclinical and clinical findings on THC and nicotine effects on selective attention, sustained attention, visuospatial attention, attentional bias, and attentional disorders across all developmental stages.

Why This Research Matters

Cannabis and nicotine are among the most commonly used substances and are often co-used. Understanding their opposing effects on attention in adults and shared harmful effects on prenatal development is important for clinical guidance and public health messaging.

The Bigger Picture

The opposing effects of THC (impairing) and nicotine (enhancing) on adult attention may partly explain why they are commonly co-used. Their shared prenatal harm, despite opposite adult effects, highlights that developmental neurotoxicity operates through different mechanisms.

What This Study Doesn't Tell Us

Narrative review methodology. Preclinical and clinical results may not be directly comparable. Dose and timing of exposure vary widely across studies. Co-use effects are understudied.

Questions This Raises

  • ?Do the opposing effects of THC and nicotine on attention interact when co-used?
  • ?Why do both substances harm prenatal attention development despite opposite adult effects?
  • ?Are there sex-specific attentional effects of cannabis that mirror nicotine findings?

Trust & Context

Key Stat:
Cannabis impairs and nicotine enhances adult attention, but both harm prenatal brain development
Evidence Grade:
Moderate: Comprehensive narrative review spanning preclinical and clinical literature across developmental stages, though narrative methodology is less rigorous than systematic review.
Study Age:
Published in 2025.
Original Title:
The Effects of THC and Nicotine on Attention: A Narrative Review.
Published In:
Current topics in behavioral neurosciences, 75, 183-238 (2025)
Database ID:
RTHC-07277

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

Summarizes existing research without a strict systematic method.

What do these levels mean? →

Frequently Asked Questions

How does cannabis affect attention?

Cannabis impairs selective attention, creates attentional bias toward cannabis-related cues, and in preclinical studies produces attention deficits that persist even after stopping use. The effect on reaction time depends on how recently cannabis was used.

Why are prenatal effects different from adult effects?

During fetal development, both substances interfere with the formation of neural circuits critical for attention, regardless of their opposing effects in the mature brain. Prenatal exposure to either substance increases risk for ADHD and other attentional disorders.

Read More on RethinkTHC

Cite This Study

RTHC-07277·https://rethinkthc.com/research/RTHC-07277

APA

Oleszak, Kennedy; Striegel, Lily Freeman; Roeder, Nicole; Mohr, Patrick; Penman, Samantha; Collins, Lorraine; Smith, Danielle M; Thanos, Panayotis K. (2025). The Effects of THC and Nicotine on Attention: A Narrative Review.. Current topics in behavioral neurosciences, 75, 183-238. https://doi.org/10.1007/7854_2024_568

MLA

Oleszak, Kennedy, et al. "The Effects of THC and Nicotine on Attention: A Narrative Review.." Current topics in behavioral neurosciences, 2025. https://doi.org/10.1007/7854_2024_568

RethinkTHC

RethinkTHC Research Database. "The Effects of THC and Nicotine on Attention: A Narrative Re..." RTHC-07277. Retrieved from https://rethinkthc.com/research/oleszak-2025-the-effects-of-thc

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.