Chronic cannabis use affects cerebellum dependent visuomotor adaptation.
C. Blithikioti, L. Miquel, B. Paniello, L. Nuño, A. Gual, B. Ballester, A. Fernandez, Ivan Herreros, Paul Verschure, M. Balcells-Oliveró
Journal of Psychiatric Research October 6, 2022 DOI: 10.1016/j.jpsychires.2022.10.007 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 52 |
| Population | Chronic cannabis users without psychiatric comorbidities and healthy cannabis-naïve controls |
| Intervention | one month of abstinence |
| Duration | 1-month abstinence retest |
| Topics | Cannabis |
| Key findings | Chronic cannabis users had lower adaptation rates than controls on a visuomotor rotation task at the first time point, but this difference did not persist after one month of abstinence in the 13 users retested. Controls showed attenuated implicit learning in the late phase of adaptation during re-exposure, which cannabis users did not, suggesting a possible alteration of synaptic plasticity required for cerebellar learning. |
Abstract
Background: Cannabis is one of the most commonly used substances in the world. However, its effects on human cognition are not yet fully understood. Although the cerebellum has the highest density of cannabinoid receptor type 1 (CB1R) in the human brain, literature on how cannabis use affects cerebellar-dependent learning is sparse. This study examined the effect of chronic cannabis use on sensorimotor adaptation, a cerebellar-mediated task, which has been suggested to depend on endocannabinoid signaling.
Methods: Chronic cannabis users (n = 27) with no psychiatric comorbidities and healthy, cannabis-naïve controls (n = 25) were evaluated using a visuomotor rotation task. Cannabis users were re-tested after 1 month of abstinence (n = 13) to assess whether initial differences in performance would persist after cessation of use.
Results: Cannabis users showed lower adaptation rates compared to controls at the first time point. However, this difference in performance did not persist when participants were retested after one month of abstinence (n = 13). Healthy controls showed attenuated implicit learning in the late phase of the adaptation during re-exposure, which was not present in cannabis users. This explains the lack of between group differences in the second time point and suggests a potential alteration of synaptic plasticity required for cerebellar learning in cannabis users.
Conclusions: Overall, our results suggest that chronic cannabis users show alterations in sensorimotor adaptation, likely due to a saturation of the endocannabinoid system after chronic cannabis use.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |