Article

Executive Dysfunction in Cocaine Addiction: Evidence for Discordant Frontal, Cingulate, and Cerebellar Activity

Medical College of Wisconsin, Milwaukee, Wisconsin, United States
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 01/2005; 24(49):11017-22. DOI: 10.1523/JNEUROSCI.3321-04.2004
Source: PubMed

ABSTRACT

Using a GO-NOGO response inhibition task in which working memory (WM) demands can be varied, we demonstrate that the compromised abilities of cocaine users to exert control over strong prepotent urges are associated with reduced activity in anterior cingulate and right prefrontal cortices, two regions thought to be critical for implementing cognitive control. Furthermore, unlike drug-naive controls, and opposite to the anterior cingulate pattern, cocaine users showed an over-reliance on the left cerebellum, a compensatory pattern previously seen in alcohol addiction. The results indicate that cocaine users find it difficult to inhibit their own actions, particularly when WM demands, which have been shown previously to increase during cue-induced craving for the drug, are increased. The results reveal a neuroanatomical basis for this dysexecutive component to addiction, supporting the suggested importance cognitive functions may play in prolonging abuse or predisposing users toward relapse.

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    • "ously highlighted in addicts by using the stop-signal task (i.e., prolonged latency of motor response inhibition), and the Go/No-Go paradigm (i.e., more errors of commission: subject had to withhold a response but pressed a button instead) (for a review of response inhibition impairment in gambling , opiate and alcohol addiction, see respectively Brevers & Noël, 2013; Goldstein & Volkow, 2011; Noël et al., 2010). Moreover, results from several brain imaging studies showed that, in drug addicts (Hester & Garavan, 2004), impaired performance on response inhibition tasks is associated with a hypoactivation in the anterior cingulate cortex, implicated in mechanisms of error detection and conflict monitoring. "
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