Current Topics in Behavioral Neurosciences
January 1, 2022
Hakan Kayır, Jessica Ruffolo, Patrick McCunn et al.
15 citations
Cannabis use affects cognition differently in schizophrenia patients versus healthy individuals. Healthy subjects who started cannabis early and used high-potency cannabis longer showed poorer working memory and attention. In schizophrenia patients, cannabis use is linked to worsened symptoms, longer and more frequent psychotic episodes, and poorer treatment outcomes. However, patients with schizophrenia who use cannabis have better overall cognitive performance than non-using patients.
Schizophrenia Bulletin
June 20, 2024
Mary F. Brunette, Robert M. Roth, Christi L. Trask et al.
5 citations
A single modest dose of oral THC (15 mg dronabinol) worsened verbal learning and attention in people with schizophrenia and co-occurring cannabis use disorder, without exacerbating psychotic symptoms several hours after administration. Smoked low-dose THC cigarettes did not produce these cognitive effects. Higher blood THC levels were linked to increased negative symptoms. Drug liking was greater with THC than placebo. The findings suggest that oral THC may impair cognition in this population even at modest doses, while not acutely worsening psychosis.
Biomolecules
September 18, 2025
Hakan Kayır, Larissa Kouroukis, Iman Aziz et al.
2 citations
Delta-9-Tetrahydrocannabivarin (THCV), a natural cannabinoid similar to THC, can both mimic and block some of THC's effects depending on dose. In a study with 16 male rats trained to distinguish THC from a placebo, THCV partially substituted for THC at 3 mg/kg (54.6% of responses), but at 6 mg/kg it reversed the effects of a low THC dose. THCV did not alter blood levels of THC or its metabolite 11-OH-THC. The results suggest THCV acts as a partial CB1 receptor agonist, producing a mix of agonist and antagonist effects.
Current Addiction Reports
February 27, 2026
Amanda C. Lee, Jibran Y. Khokhar
Cannabis use is linked to schizophrenia, especially in vulnerable people. Preclinical rodent models help clarify this relationship by allowing controlled experiments that are impossible in humans. Recent studies use advanced paradigms, including translationally-relevant rodent models and ecologically valid cannabis administration routes, to simulate human use patterns and vulnerability. These models show that cannabinoid exposure can alter schizophrenia-like behaviors and neural effects related to hyperlocomotion, sensorimotor gating deficits, social withdrawal, and anhedonia. The route of administration, dose, and type of cannabinoid shape these outcomes. Such findings identify periods of heightened vulnerability and inform prevention and intervention strategies.
Schizophrenia Research
April 1, 2018
Susan Whitfield-Gabrieli, Adina S Fischer, Angela Henricks et al.
In a pilot study, patients with schizophrenia and cannabis use disorder showed over-connectivity in the default mode network (DMN) at rest, which correlated with more severe positive symptoms, and reduced anticorrelation between the DMN and the executive control network (ECN). After smoking a 3.6% THC cannabis cigarette or ingesting a 15 mg THC pill, DMN hyperconnectivity decreased and DMN-ECN anticorrelation increased. The degree of anticorrelation in healthy controls and in patients after cannabinoid administration positively correlated with working memory performance. The results suggest that DMN connectivity can change, which may inform future treatments targeting circuit-level dysfunction.