Background: Regions undergoing maturation with CB1 receptors may be at increased risk for cannabis-induced alterations. Here, we examine the relationships between cannabis use and prefrontal (PFC) and inferior parietal gyrification and surface area (SA) in youth.
Methods: Participants included 33 cannabis users and 35 controls (ages 18-25). Exclusions included co-morbid psychiatric/neurologic disorders and heavy other drug use. Multiple regressions and Pearson r correlations examined the effects of cannabis use on gyrification, SA and cognition.
Results: Cannabis use was associated with decreased gyrification in: ventral-medial PFC (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]); medial PFC (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]); and frontal poles (RH: [FDR corrected p=.02], LH: [FDR corrected p=.02]). No differences were observed in bilateral hemispheres, PFC, dorsolateral, ventrolateral, or inferior parietal ROIs. Cannabis use was associated with marginally decreased SA in left: medial PFC [FDR corrected p=.09], and ventral lateral PFC: [FDR corrected p=.09]. In cannabis users, increased gyrification was associated with improved working-memory performance in right medial (p=.003), ventral-medial (p=.03), and frontal pole ROIs (p=.007).
Conclusions: Cannabis use was associated with reduced gyrification in PFC regions implicated in self-referential thought and social cognition. Results suggest that these gyrification characteristics may have cognitive implications.
Keywords: Cannabis; Cognition; Emerging adults; Gyrification; Marijuana; Prefrontal and parietal cortex.
Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.