Chronic use of cannabis and poor neural efficiency in verbal memory ability.
Robert A Battisti, Steven Roodenrys, Stuart J Johnstone, Colleen Respondek, Daniel F. Hermens, Nadia Solowij
Psychopharmacology May 2010 DOI: 10.1007/s00213-010-1800-4 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 48 |
| Population | 24 chronic cannabis users and 24 non-using controls |
| Measures | event-related potential (ERP), subsequent memory effect (SME) |
| Topics | Cannabis |
| Key findings | Cannabis users showed poorer recall and altered SME activation, with attenuated N4 and increased late positive component. Duration and earlier onset of use correlated with greater alterations, suggesting lasting memory-related brain changes. |
Abstract
The endogenous cannabinoid system is sensitive to the introduction of exogenous cannabinoids such as delta-9-tetrahydrocannabinol, which are known to impact upon memory functioning. We sought to examine the impact of chronic cannabis use upon memory-related brain function via examination of the subsequent memory effect (SME) of the event-related potential (ERP). The SME is predictive of recall outcome and originates in structures that are dense with cannabinoid receptors (hippocampus and parahippocampus). The SME and performance on a verbal memory task were compared between 24 cannabis users (mean 17 years of near daily use) in the unintoxicated state and 24 non-using controls. The task involved the presentation of word lists, each with a short delay before recall. ERPs were recorded during encoding and later averaged by outcome (correctly recalled/not recalled). Cannabis users showed poorer recall and altered patterns of SME activation: specifically, attenuation of the negative N4 and an increase in the late positive component. Duration of cannabis use and age of initial use correlated significantly with SME amplitudes. A longer history of use also correlated with greater recall that was related to N4 expression. The results indicate that relative to non-using controls, chronic users of cannabis have altered memory-related brain activation in the form of dysfunctional SME production and/or poorer neural efficiency, which is associated with deficits in memory recall. Greater alteration was associated with a longer history of cannabis use and an earlier onset of use. Neuroadaptation to the effects of chronic exposure may additionally play a role.
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 16
- Cannabis use and cognitive dysfunction Indian Journal of Psychiatry 2011
- Cannabis affects people differently: inter-subject variation in the psychotogenic effects of Δ9-tetrahydrocannabinol: a functional magnetic resonance imaging study with healthy volunteers Psychological Medicine October 1, 2012
- Verbal Memory Performance and Reduced Cortical Thickness of Brain Regions Along the Uncinate Fasciculus in Young Adult Cannabis Users Cannabis and Cannabinoid Research March 29, 2018
- Impact of cannabis use on brain metabolism using 31P and 1H magnetic resonance spectroscopy Neuroradiology September 22, 2023
- Prolonged incubation with Δ9-tetrahydrocannabinol but not with cannabidiol induces synaptic alterations and mitochondrial impairment in immature and mature rat organotypic hippocampal slices. Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie February 1, 2025
and 11 more in the library
Cites 6
- Neurophysiological and subjective profile of marijuana with varying concentrations of cannabinoids Behavioural Pharmacology September 1, 2005
- Neurocognitive performance during acute THC intoxication in heavy and occasional cannabis users. Journal of Psychopharmacology May 2009
- The effect of cannabis use and gender on the visual steady state evoked potential. Clinical Neurophysiology January 2006
- Functional tolerance and blockade of long-term depression at synapses in the nucleus accumbens after chronic cannabinoid exposure. Journal of Neuroscience June 15, 2003
- Regulation of cannabinoid CB1 receptors in the central nervous system by chronic cannabinoids. Critical reviews in neurobiology 2003
and 1 more in the library