Prenatal cannabis exposure linked to attention and behavior problems at age 10 but no brain scan differences

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. However, PCE did not affect cognitive performance on response inhibition, reward processing, or working memory tasks, and showed no differences in brain activation patterns during fMRI.

Data from the ABCD Study (approximately 12,000 children). 224 children with PCE (reported by caregivers) compared to two control groups: tobacco/alcohol-matched and unexposed. Behavioral outcomes from CBCL at ages 9-10. Cognitive and fMRI measures from three tasks: Stop Signal (response inhibition), MID (reward), and EN-Back (working memory).

Using the largest adolescent brain development study in the world, this research shows that prenatal cannabis exposure is associated with behavioral but not cognitive or neuroimaging differences by age 10, though later effects may emerge.

The disconnect between behavioral problems and normal cognitive/neuroimaging findings mirrors the broader ADHD literature, where fewer than half of children with attention problems show specific cognitive deficits, suggesting behavioral impacts operate through mechanisms not captured by standard cognitive tests.

Caregiver-reported PCE may underestimate exposure. Cannot control for all confounders (genetics, postnatal environment). Cross-sectional analysis at one age point. fMRI tasks may not be sensitive enough. Children are still developing.