Mismatch Negativity and P50 Sensory Gating in Abstinent Former Cannabis Users
Samantha J Broyd, L. Greenwood, Hendrika H Van Hell, Rodney J. Croft, Hannah L. Coyle, Ben Lee-Bates, J. Todd, Stuart J Johnstone, P. Michie, Nadia Solowij
Journal of Neural Transplantation and Plasticity February 25, 2016 DOI: 10.1155/2016/6526437 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 36 |
| Population | 18 ex-cannabis users (median 13.5 years prior regular use; median 3.5 years abstinence) and 18 nonusers |
| Duration | Median 3.5 years abstinence |
| Measures | mismatch negativity (MMN), P50 sensory gating |
| Topics | Cannabis |
| Key findings | Former chronic cannabis users showed trend-level smaller duration MMN amplitude and larger P50 ratios (poorer sensory gating) than nonusers, suggesting these impairments tend to persist after prolonged abstinence. Poorer P50 gating correlated with longer prior cannabis use, while longer abstinence correlated with greater duration MMN amplitude, which the authors suggest may relate to self-medication or accelerated aging. |
Abstract
Prolonged heavy exposure to cannabis is associated with impaired cognition and brain functional and structural alterations. We recently reported attenuated mismatch negativity (MMN) and altered P50 sensory gating in chronic cannabis users. This study investigated the extent of brain functional recovery (indexed by MMN and P50) in chronic users after cessation of use. Eighteen ex-users (median 13.5 years prior regular use; median 3.5 years abstinence) and 18 nonusers completed (1) a multifeature oddball task with duration, frequency, and intensity deviants and (2) a P50 paired-click paradigm. Trend level smaller duration MMN amplitude and larger P50 ratios (indicative of poorer sensory gating) were observed in ex-users compared to controls. Poorer P50 gating correlated with prior duration of cannabis use. Duration of abstinence was positively correlated with duration MMN amplitude, even after controlling for age and duration of cannabis use. Impaired sensory gating and attenuated MMN amplitude tended to persist in ex-users after prolonged cessation of use, suggesting a lack of full recovery. An association with prolonged duration of prior cannabis use may indicate persistent cannabis-related alterations to P50 sensory gating. Greater reductions in MMN amplitude with increasing abstinence (positive correlation) may be related to either self-medication or an accelerated aging process.
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 2
Cites 12
- Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study BMJ March 1, 2011
- Cellular and intracellular mechanisms involved in the cognitive impairment of cannabinoids. Philosophical transactions of the Royal Society of London. Series B, Biological sciences December 5, 2012
- Auditory mismatch negativity deficits in long-term heavy cannabis users. European Archives of Psychiatry and Clinical Neuroscience September 2010
- Reduced expression of glutamate receptors and phosphorylation of CREB are responsible for in vivo Delta9-THC exposure-impaired hippocampal synaptic plasticity. Journal of Neurochemistry February 2010
- Sensory Gating Impairments in Heavy Cannabis Users are Associated with Altered Neural Oscillations Behavioral Neuroscience August 1, 2009
and 7 more in the library