Effects of marijuana use on prefrontal and parietal volumes and cognition in emerging adults. Psychopharmacology (Berl) 2015 Aug;232(16):2939-50
Date
04/30/2015Pubmed ID
25921032Pubmed Central ID
PMC4533900DOI
10.1007/s00213-015-3931-0Scopus ID
2-s2.0-84937970686 (requires institutional sign-in at Scopus site) 52 CitationsAbstract
RATIONALE: Chronic marijuana (MJ) use among adolescents has been associated with structural and functional abnormalities, particularly in developing regions responsible for higher order cognition.
OBJECTIVES: This study investigated prefrontal (PFC) and parietal volumes and executive function in emerging adult MJ users and explored potential gender differences.
METHODS: Participants (ages 18-25) were 27 MJ users and 32 controls without neurologic or psychiatric disorders or heavy other drug use. A series of multiple regressions examined whether group status, past year MJ use, and their interactions with gender predicted ROI volumes. Post hoc analyses consisted of brain-behavior correlations between volumes and cognitive variables and Fisher's z tests to assess group differences.
RESULTS: MJ users demonstrated significantly smaller medial orbitofrontal (mOFC; p = 0.004, FDR p = 0.024) and inferior parietal volumes (p = 0.04, FDR p = 0.12); follow-up regressions found that increased past year MJ use did not significantly dose-dependently predict smaller mOFC volume in a sub-sample of individuals with at least one past year MJ use. There were no significant gender interactions. There was a significant brain-behavior difference by group, such that smaller mOFC volumes were associated with poorer complex attention for MJ users (p < 0.05).
CONCLUSIONS: Smaller mOFC volumes among MJ users suggest disruption of typical neurodevelopmental processes associated with regular MJ use for both genders. These results highlight the need for longitudinal, multi-modal imaging studies providing clearer information on timing of neurodevelopmental processes and neurocognitive impacts of youth MJ initiation.
Author List
Price JS, McQueeny T, Shollenbarger S, Browning EL, Wieser J, Lisdahl KMAuthor
Jenessa Price PhD Associate Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdolescentAdult
Cannabis
Cognition
Executive Function
Female
Humans
Male
Marijuana Abuse
Marijuana Smoking
Organ Size
Parietal Lobe
Prefrontal Cortex
Sex Characteristics
Young Adult
