Regional and cannabis-related differences in prefrontal multiscale entropy of resting-state EEG.
William T Creel, Colleen A Brenner, Richard E Hartman
Clinical neurophysiology practice January 1, 2026 DOI: 10.1016/j.cnp.2026.02.003 via PubMed
Summary
AI-generated from the abstractFrequent cannabis use is associated with reduced neural signal complexity in the prefrontal cortex, as measured by multiscale entropy (MSE) of resting-state EEG. In 57 adults—non-users, low-frequency users (≤1x/week), and frequent users (≥2x/week)—MSE increased with coarser temporal scales in all groups, but the slope was significantly flatter in frequent users. From medium to very-coarse scales, their prefrontal entropy slope was 0.12 to 0.16 bits lower than non-users. Across all participants, the prefrontal cortex showed lower MSE than parietal, occipital, and temporal lobes, with larger differences at coarser scales. MSE detects cannabis-related reductions in prefrontal signal complexity at longer temporal scales.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 57 |
| Population | Adults categorized as non-users, low-frequency users (≤1x/week), and frequent users (≥2x/week) of cannabis |
| Topics | Cannabis |
| Keywords | Electroencephalography Entropy Neurophysiology Prefrontal cortex |
| Key finding | Frequent cannabis users show a significantly flatter prefrontal cortex multiscale entropy slope, indicating reduced neural signal complexity at longer temporal scales. |
Abstract
Entropy analysis of electroencephalographic (EEG) data provides insight into the complexity of neural activity. This study primarily examined whether cannabis use frequency is associated with alterations in multiscale entropy (MSE) in the prefrontal cortex (PFC) and mapped baseline MSE differences across cortical regions. Resting-state EEG was collected from 57 adults: non-users (n = 18), low-frequency users (≤ 1x/week; n = 24), and frequent users (≥ 2x/week; n = 15). MSE values were binned into fine, medium, coarse, and very-coarse scale ranges. Linear mixed-effects models assessed group × scale bin interactions in the PFC and regional differences among lobes, irrespective of cannabis use. Entropy increased with coarser scales in all groups, but the slope was significantly flatter in frequent users. From the medium bin onward, their PFC scale-entropy slope was ∼ 0.12 bits lower than in non-users, widening to ∼ 0.16 bits at very-coarse scales (FDR-corrected q < 0.012). Across all participants, the PFC exhibited lower MSE than parietal, occipital, and temporal lobes, with regional gaps expanding at coarser scales. The PFC exhibits intrinsically reduced signal complexity compared with other cortical regions, with further attenuation in frequent cannabis users. MSE captures regional cortical dynamics in resting EEG and detects cannabis-related reductions in prefrontal signal complexity at longer temporal scales.