Poster C107, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Motor learning deficits in cannabis users
Shikha Prashad1, Elizabeth Dedrick1, Francesca Filbey1; 1University of Texas at Dallas
Despite the importance of motor learning for performing activities of daily living, little is known about the preservation of this ability in cannabis users. Studies have reported cognitive deficits and structural and functional changes associated with cannabis use. Animal models indicate that the basal ganglia, cerebellum, and hippocampus have the highest densities of cannabinoid 1 receptors. Thus, the endocannabinoid system involves complex interactions between cannabis use, cognition, and motor activity that are yet to be investigated. The goal of this study was to examine motor learning deficits in cannabis users. Ten cannabis users (5 females; mean age: 30.3 years) performed the serial reaction time (SRT) task while undergoing electroencephalography (EEG). In the SRT task, learning was assessed via an improvement in response times during the learning blocks. We found that mean response time did not improve, indicating impaired motor learning in cannabis users. Fast Fourier transform (FFT) on the EEG data revealed that alpha power was significantly higher than beta power throughout the SRT task (p = 0.03). A decrease in alpha power and an increase in beta power is expected when engaged in a task, but these changes in power were not exhibited within either frequency. The alpha and beta frequency bands may be potential biomarkers for cognitive motor impairments in cannabis use disorder. Taken together, our results suggest impaired motor learning in cannabis users that can be observed behaviorally and neurally. These results are critical for treatment and rehabilitation strategies and have public health and policy implications.
Topic Area: LONG-TERM MEMORY: Skill learning