Altered cerebellar-cortical resting-state functional connectivity in cannabis users
Ashley M. Schnakenberg Martin, Dae-Jin Kim, Sharlene D. Newman, Hu Cheng, W. Hetrick, K. Mackie, B. O’Donnell
Journal of Psychopharmacology May 25, 2021 DOI: 10.1177/02698811211019291 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 72 |
| Population | Regular cannabis users and healthy non-using peers |
| Topics | Cannabis |
| Key findings | Cannabis users show hyperconnectivity between anterior cerebellar regions and the posterior cingulate cortex, and hypoconnectivity between most other cerebellar regions and the cortex. |
Abstract
Background: Cannabis use has been associated with abnormalities in cerebellar mediated motor and non-motor (i.e. cognition and personality) phenomena. Since the cerebellum is a region with high cannabinoid type 1 receptor density, these impairments may reflect alterations of signaling between the cerebellum and other brain regions.
Aims: We hypothesized that cerebellar-cortical resting-state functional connectivity (rsFC) would be altered in cannabis users, relative to their non-using peers. It was also hypothesized that differences in rsFC would be associated with cannabis use features, such as age of initiation and lifetime use.
Methods: Cerebellar-cortical and subcortical rsFCs were computed between 28 cerebellar lobules, defined by a spatially unbiased atlas template of the cerebellum, and individual voxels in the cerebral regions, in 41 regular cannabis users (20 female) and healthy non-using peers (N = 31; 18 female). We also investigated associations between rsFC and cannabis use features (e.g. lifetime cannabis use and age of initiation).
Results: Cannabis users demonstrated hyperconnectivity between the anterior cerebellar regions (i.e. lobule I-IV) with the posterior cingulate cortex, and hypoconnectivity between the rest of the cerebellum (i.e. Crus I and II, lobule VIIb, VIIIa, VIIIb, IX, and X) and the cortex. No associations were observed between features of cannabis use and rsFC.
Conclusions: Cannabis use was associated with altered patterns of rsFC from the cerebellum to the cerebral cortex which may have a downstream impact on behavior and cognition.