Schedule of Events | Symposia

Chronic cannabis use modulates gamma functional connectivity with V1 during visual entrainment

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Lauren K. Webert¹ (lauren.webert@boystown.org), Nathan M. Petro¹, Seth D. Springer¹, Jason A. John¹, Lucy K. Horne¹, Hannah J. Okelberry¹, Ryan Glesinger¹, Maggie P. Rempe¹, Tony W. Wilson¹; ¹Boys Town National Research Hospital, Omaha, NE

Cannabis is one of the most commonly used illicit substances in the United States, and its chronic use has been linked to deficits across multiple cognitive domains. Mechanistically, cannabis acts upon endocannabinoid receptors, which are densely distributed among GABAergic interneurons throughout the cortex and cerebellum. Such interneuronal networks have been linked to many aspects of visual perception and information processing across the cortex vis-à-vis neural gamma oscillations. However, it remains less understood how chronic cannabis use modulates gamma activity and dynamic functional connectivity (FC) in the gamma range. Herein, 84 cannabis users and 90 nonusers underwent high-density magnetoencephalography during visual entrainment at three separate gamma-band frequencies (32, 40, and 48 Hz). The resulting data were source-imaged in the time-frequency domain and submitted to statistical models to test for effects of hemisphere, frequency, and group. Our results indicated strong entrainment responses across all frequencies in the bilateral primary visual cortices (V1). Across groups, 32 Hz elicited the strongest entrainment response, followed by 40 Hz, and finally 48 Hz stimulation within bilateral V1 (p<.001). Additionally, participants exhibited stronger entrainment in the right relative to left V1 across all entrainment conditions (p=.002). Group-by-condition interactions in FC (p<.005) revealed that cannabis users, compared to nonusers, exhibited elevated V1-right cerebellum FC at 32 Hz, and elevated V1-left inferior frontal gyrus (IFG) FC at 32 and 40 Hz. Our findings suggest that visual entrainment is robust across the gamma spectrum in V1, and that chronic cannabis use modulates V1-cerebellar and V1-IFG connectivity in the gamma range.

Topic Area: PERCEPTION & ACTION: Vision