Children exposed to cannabis before birth showed blunted brain reward responses that predicted psychotic-like experiences, with effects tracked across 4 years in over 11,000 youth.
Pregnant individuals, OB-GYNs, child psychiatrists, neuroscientists, and public health policymakers
What the researchers found
Prenatal cannabis exposure (652 youth) was longitudinally associated with psychotic-like experiences, mediated by blunted striatal activation during reward anticipation — a marker of disrupted endocannabinoid-dopamine function.
Why it matters
This provides a biological mechanism linking prenatal cannabis exposure to later psychosis risk — disrupted reward processing in the developing brain may be the bridge between in-utero exposure and adolescent mental health outcomes.
The numbers in context
11,368 youth at baseline; 652 with prenatal cannabis exposure; effects tracked across 4 years at 22 US sites; all effect sizes |β|>0.5 with FDR-corrected significance.
How the study worked
Longitudinal prospective study analyzing task-related fMRI data from the ABCD Study at baseline (N=11,368), 2-year (n=7,928), and 4-year (n=2,982) follow-ups, examining reward anticipation neural responses.
What this study cannot tell us
Prenatal exposure based on maternal report, which may underestimate true exposure; ABCD cohort may not be fully representative; fMRI measures are indirect indicators of neural function.
How to read the evidence
Large prospective longitudinal study from the premier US adolescent brain development cohort with neuroimaging biomarkers and multi-year follow-up.
When this study was published
Published in 2026 from the ongoing ABCD Study, representing the most current large-scale data on prenatal cannabis effects.
The bigger picture
With prenatal cannabis use rising alongside legalization, understanding how fetal exposure alters brain development has urgent public health implications for prevention messaging and early intervention.
Questions still open
- Could early reward-processing interventions mitigate psychosis risk in prenatally exposed children? Is there a dose-response relationship between prenatal cannabis exposure level and neural disruption?
Common questions
Can cannabis use during pregnancy affect a child's brain development?
What are psychotic-like experiences in children?
Read the original research
Altered Neurobehavioral Reward Response Predicts Psychotic-Like Experiences in Youth Exposed to Cannabis Prenatally.
Biological psychiatry, 99(2), 165-174
Citation
Amir, Carolyn M; Ghahremani, Dara G; Chang, Sarah E; Cooper, Ziva D; Bearden, Carrie E. (2026). Altered Neurobehavioral Reward Response Predicts Psychotic-Like Experiences in Youth Exposed to Cannabis Prenatally.. Biological psychiatry, 99(2), 165-174. https://doi.org/10.1016/j.biopsych.2025.05.019
Explore the wider topic
- How to Talk to Your Teenager About Weed (Without Losing Them)
- My Kid's Friends Smoke Weed: A Parent's Guide
- I Smoke Weed But Don't Want My Kids To: Navigating the Hypocrisy
- Quitting Weed as a Parent: Why It Is the Hardest and Most Important Quit
- Quitting Weed as a Teen or Young Adult
- My Kid Is Smoking Weed: A Parent's Guide