Effects of prenatal cannabis exposure on visual-perceptual processing and brain volume were not uniform but appeared to become more apparent as children developed from ages 9-11 to 11-13.
Developmental neuroscientists, pediatricians, prenatal health researchers, and public health educators.
697 exposed childrenin the ABCD Study showed increasingly divergent brain and cognitive trajectories compared to 10,833 unexposed peers
What the researchers found
Significant interactions between time and prenatal cannabis exposure were found for visuo-perceptual processing ability (b=-0.019, p=.009) and intracranial volumes (b=-6338.309, p=.009), suggesting effects magnify over development.
Why it matters
If prenatal cannabis effects become stronger over time rather than remaining stable, this suggests ongoing developmental vulnerability that may not be apparent in early childhood assessments.
The numbers in context
11,876 children at baseline (age 9-11), 10,414 at 2-year follow-up from 22 US sites. 10,833 with no prenatal cannabis exposure, 697 with exposure. Significant time x exposure interactions for visual processing and brain volume.
How the study worked
Longitudinal analysis of ABCD Study data at two time points, examining associations between prenatal cannabis exposure and developmental trajectories of cognitive abilities and brain volumes.
Who was studied
11,530 children aged 9-13 from 22 sites across the United States in the ABCD Study.
What this study cannot tell us
Prenatal cannabis exposure was retrospectively reported by mothers. Cannot fully control for co-exposures (tobacco, alcohol). Two time points limit trajectory modeling. Effect sizes may be small.
How to read the evidence
Large longitudinal cohort study with neuroimaging; strong design but retrospective exposure assessment limits causal claims.
When this study was published
Uses ABCD Study data, the largest ongoing US study of adolescent brain development.
The bigger picture
The ABCD Study is the largest long-term study of brain development in the US. These findings suggest prenatal cannabis effects are not static but may compound over development, raising concerns about later academic and cognitive outcomes.
Replication
Part of the ongoing ABCD Study; further time points will strengthen or qualify these findings.
Funding
Not specified in abstract
Conflicts of interest
Not specified in abstract
Questions still open
- Will these effects continue to magnify into adolescence and young adulthood?
- Are specific brain regions or cognitive domains more vulnerable to escalating prenatal cannabis effects?
Read the original research
Effects of prenatal cannabis exposure on developmental trajectory of cognitive ability and brain volumes in the adolescent brain cognitive development (ABCD) study.
Developmental cognitive neuroscience, 60, 101209
Citation
Hiraoka, Daiki; Makita, Kai; Hamatani, Sayo; Tomoda, Akemi; Mizuno, Yoshifumi. (2023). Effects of prenatal cannabis exposure on developmental trajectory of cognitive ability and brain volumes in the adolescent brain cognitive development (ABCD) study.. Developmental cognitive neuroscience, 60, 101209. https://doi.org/10.1016/j.dcn.2023.101209