Among over 10,700 children, prenatal cannabis exposure before the mother knew she was pregnant was associated with weaker connectivity between brain networks involved in attention and emotional processing.
Read this if you are interested in how prenatal cannabis exposure affects child brain development.
10,719 childrenLarge-scale ABCD study linking prenatal cannabis to altered brain network connectivity at age 10
What the researchers found
Using data from 10,719 children (mean age ~10) in the ABCD study, prenatal cannabis exposure before knowledge of pregnancy was associated with lower resting-state connectivity between the salience network and ventral attention network. Exposure after pregnancy knowledge was not significantly associated with connectivity changes. Psychotic-like experiences mediated the relationship between prenatal cannabis exposure and altered connectivity, but this mediation was not significant after including covariates.
Why it matters
The salience network is critical for detecting and responding to important stimuli. Weakened connectivity with attention networks could explain previously observed associations between prenatal cannabis exposure and behavioral problems in children.
The numbers in context
- 10,719 children from ABCD study
- Mean age: 9.92±0.62 years; 47.9% female
- Prenatal cannabis exposure before pregnancy knowledge: associated with lower SN-VAN connectivity
- Prenatal exposure after pregnancy knowledge: not significant
- Mediation by psychotic-like experiences: significant but lost with covariates
How the study worked
Cross-sectional analysis of the Adolescent Brain Cognitive Development (ABCD) study. Resting-state fMRI assessed functional connectivity within and between six core neurocognitive networks. Parent-reported prenatal cannabis exposure. Mediation analysis for psychotic-like experiences.
Who was studied
10,719 children (~10 years old) from the Adolescent Brain Cognitive Development (ABCD) study
What this study cannot tell us
Prenatal exposure was parent-reported retrospectively (10 years later). Cross-sectional design. Mediation effects were not robust to covariate adjustment. Cannot separate cannabis effects from other prenatal exposures or postnatal environmental factors.
How to read the evidence
Large population-based neuroimaging study from the ABCD cohort. Strong sample size but limited by retrospective exposure data and cross-sectional design.
When this study was published
Published in 2023. Uses the largest US brain development study to investigate prenatal cannabis effects.
The bigger picture
The ABCD study is the largest long-term study of brain development in the US. These findings add neuroimaging evidence to the growing body of research on prenatal cannabis effects, though the complexity of confounders in this area remains a major challenge.
Questions still open
- Why does exposure before pregnancy knowledge show effects but exposure after does not?
- Do these connectivity differences persist or change through adolescence?
- Can the SN-VAN connectivity finding be replicated in other developmental cohorts?
Read the original research
Impact of prenatal cannabis exposure on functional connectivity of the salience network in children.
Journal of neuroscience research, 101(1), 162-171
Citation
Faraj, Mohammed M; Evanski, Julia; Zundel, Clara G; Peters, Craig; Brummelte, Susanne; Lundahl, Leslie; Marusak, Hilary A. (2023). Impact of prenatal cannabis exposure on functional connectivity of the salience network in children.. Journal of neuroscience research, 101(1), 162-171. https://doi.org/10.1002/jnr.25136