Altered Fronto-Occipital Connectivity during Visual Selective Attention in Regular Cannabis Users
Abril Rangel-Pacheco, Brandon J. Lew, Mikki D. Schantell, Michaela R. Frenzel, Jacob A. Eastman, Alex I. Wiesman, T. Wilson
Psychopharmacology November 25, 2020 DOI: 10.1007/s00213-020-05717-3 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case-control study Peer reviewed |
|---|---|
| Sample size | 48 |
| Population | 24 adults reporting at least weekly cannabis use in the past 6 months and 24 demographically matched controls reporting no prior cannabis use |
| Measures | Cannabis Use Disorder Identification Test - Revised |
| Topics | Cannabis |
| Key findings | Regular cannabis users performed within the normal range on a visual selective attention task but showed an abnormal theta-band (4-8 Hz) interference effect in the right occipital cortex 0-250 ms after stimulus onset and altered right prefrontal-occipital functional connectivity in the theta range. The authors suggest these differences may reflect compensatory processing. |
Abstract
Cognitive processing impairments have been associated with acute cannabis use, but there is mixed evidence regarding the cognitive effects of chronic cannabis use. Several neuroimaging studies have noted selective-attention processing differences in those who chronically use cannabis, but the neural dynamics governing the altered processing is unclear. Twenty-four adults reporting at least weekly cannabis use in the past 6 months on the Cannabis Use Disorder Identification Test – Revised were compared to 24 demographically matched controls who reported no prior cannabis use. All participants completed a visual selective attention processing task while undergoing magnetoencephalography. Time-frequency windows of interest were identified using a data-driven method, and spectrally specific neural activity was imaged using a beamforming approach. All participants performed within normal range on the cognitive task. Regular cannabis users displayed an aberrant cognitive interference effect in the theta (4–8 Hz) frequency range shortly after stimulus onset (i.e., 0–250 ms) in the right occipital cortex. Cannabis users also exhibited altered functional connectivity between the right prefrontal cortex and right occipital cortices in comparison to controls. Individuals with a history of regular cannabis use exhibited abnormal theta interference activity in the occipital cortices, as well as altered prefrontal-occipital functional connectivity in the theta range during a visual selective attention task. Such differences may reflect compensatory processing, as these participants performed within normal range on the task. Understanding the neural dynamics in chronic, regular cannabis users may provide insight on how long-term and/or frequent use may affect neural networks underlying cognitive processes.