Cannabis Use Linked to Altered Functional Connectivity of the Visual Attentional Connectivity in Patients With Psychosis and Controls
Musa Sami, Robert A. McCutcheon, Ulrich Ettinger, Steven C. R. Williams, David J Lythgoe, P. McGuire, Sagnik Bhattacharyya
Schizophrenia Bulletin Open 2020 DOI: 10.1093/schizbullopen/sgaa018 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 92 |
| Population | Patients with early psychosis and healthy controls, with and without cannabis use |
| Topics | Cannabis |
| Key findings | Patients with early psychosis and a history of cannabis use showed increased connectivity in the dorsal attention network and between visual and dorsal attention networks compared to non-using controls, and these connectivity measures correlated with visual hallucinations and cannabis dependence severity. |
Abstract
Both chronic cannabis use and psychotic disorders are associated with abnormalities in visual attentional processing. Using functional magnetic resonance imaging (fMRI), we sought to determine whether there would be a difference in functional connectivity in patients and controls with and without a history of cannabis use in the visual and dorsal attention networks. Resting-state fMRI data were acquired in patients with early psychosis with (EPC = 29) and without (EPNC = 25); and controls with (HCC = 16) and without (HCNC = 22) cannabis use. There was a patient effect in both Visual-Dorsal Attention Internetwork (F(1,87) = 5.326, P = .023) and the Visual Network (F(1,87) = 4.044, P = .047) and a cannabis effect in the Dorsal Attention Network (F(1,87) = 4.773, P = .032). These effects were specific to the networks examined with no evidence for significant patient or cannabis effects in other canonical networks. Patients with a history of cannabis use showed increased connectivity in the Dorsal Attention Network (134%, P = .019) and Visual Dorsal Attention Internetwork (285%, P = .036) compared to non-using controls. In the EPC group connectivity of the Visual Network (ρ = 0.379, P = .042) and Visual-Dorsal Attention Internetwork (ρ = 0.421, P = .023) correlated with visual hallucinations which were significantly different from EPNC (P = .011). Dorsal attention network strength correlated with severity of dependence for cannabis (ρ = 0.215, P = .04). We demonstrate specific cannabis and patient effects in networks associated with visual attentional processing. There is a differential association with hallucinatory symptoms in patients with and without a history of cannabis use. This may indicate that dysconnectivity in these networks serves different roles in the context of cannabis use.
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 3
- Functional brain connectomes reflect acute and chronic cannabis use Scientific Reports February 14, 2022
- EEG-based network dynamics in cannabis and polydrug use: a directed transfer function approach. Psychopharmacology October 20, 2025
- Disrupted Resting State Attentional Network Connectivity in Adolescent and Young Adult Cannabis Users following Two-Weeks of Monitored Abstinence Brain Sciences February 24, 2022
Cites 11
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- Differential associations of combined versus isolated cannabis and nicotine on brain resting state networks Brain Structure and Function June 7, 2018
- Understanding marijuana's effects on functional connectivity of the default mode network in patients with schizophrenia and co-occurring cannabis use disorder: A pilot investigation. Schizophrenia Research April 1, 2018
and 6 more in the library