Cannabis users exhibit increased cortical activation during resting state compared to non-users
S. Prashad, Elizabeth S. Dedrick, F. Filbey
Neuroimage June 9, 2018 DOI: 10.1016/j.neuroimage.2018.06.031 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 38 |
| Population | Cannabis users and non-using controls matched for age and sex |
| Topics | Cannabis |
| Key findings | Cannabis users exhibited decreased delta and increased theta, beta, and gamma power, along with increased interhemispheric and intrahemispheric coherence, compared to controls. |
Abstract
&NA; Studies have shown altered task‐based brain functioning as a result of cannabis use. To date, however, whether similar alterations in baseline resting state and functional organization of neural activity are observable in cannabis users remains unknown. We characterized global resting state cortical activations and functional connectivity via electroencephalography (EEG) in cannabis users and related these activations to measures of cannabis use. Resting state EEG in the eyes closed condition was collected from age‐ and sex‐matched cannabis users (N = 17; 6 females; mean age = 30.9 ± 7.4 years) and non‐using controls (N = 21; 9 females; mean age = 33.1 ± 11.6 years). Power spectral density and spectral coherence were computed to determine differences in cortical activations and connectivity between the two groups in the delta (1–4Hz), theta (4–7 Hz), alpha (8–12 Hz), beta (13–30 Hz), and gamma (31–50 Hz) frequency bands. Cannabis users exhibited decreased delta and increased theta, beta, and gamma power compared to controls, suggesting increased cortical activation in resting state and a disinhibition of inhibitory functions that may interrupt cognitive processes. Cannabis users also exhibited increased interhemispheric and intrahemispheric coherence relative to controls, reduced mean network degree, and increased clustering coefficient in specific regions and frequencies. This increased cortical activity may indicate a loss of neural refinement and efficiency that may indicate a “noisy” brain. Lastly, measures related to cannabis use were correlated with spectral power and functional connectivity measures, indicating that specific electrophysiological signals are associated with cannabis use. These results suggest that there are differences in cortical activity and connectivity between cannabis users and non‐using controls in the resting state that may be related to putative cognitive impairments and can inform effectiveness of intervention programs. HighlightsGlobal resting state cortical activity in cannabis users was measured using EEG.Users exhibited increased cortical activity and connectivity compared to controls.Increased activity reflects a noisy brain with loss of neural refinement and efficiency.This increase may underlie putative cognitive impairments in cannabis users.EEG signals may be useful neural correlates for tracking progress and efficacy of interventions.
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 |
Citations in the library
Cited by 13
- Not Just a Pot: Visual Episodic Memory in Cannabis Users and Polydrug Cannabis Users: ROC and ERP Preliminary Investigation Frontiers in Human Neuroscience June 11, 2021
- Theta and Alpha Oscillatory Activity During Working Memory Maintenance in Long-Term Cannabis Users: The Importance of the Polydrug Use Context Frontiers in Human Neuroscience October 18, 2021
- The antioxidant N-acetylcysteine prevents cortical neuropathological phenotypes caused by adolescent Δ-9-tetrahydrocannabinol exposure in male rats. Translational Psychiatry October 6, 2025
- Longer chronic cannabis use in humans is associated with impaired implicit motor learning and supranormal resting state cortical activity bioRxiv (Cold Spring Harbor Laboratory) April 21, 2025
- Wpływ marihuany na aktywność elektryczną mózgu Kosmos April 11, 2020
and 8 more in the library
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