Hester Robert, Garavan Hugh
Department of Psychology and Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
J Neurosci. 2004 Dec 8;24(49):11017-22. doi: 10.1523/JNEUROSCI.3321-04.2004.
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.
使用一种可以改变工作记忆(WM)需求的停止信号反应抑制任务,我们证明了可卡因使用者对强烈的优势冲动施加控制的能力受损,与前扣带回和右前额叶皮质活动减少有关,这两个区域被认为对实施认知控制至关重要。此外,与未使用过药物的对照组不同,并且与前扣带回模式相反,可卡因使用者对左侧小脑表现出过度依赖,这是先前在酒精成瘾中看到的一种代偿模式。结果表明,可卡因使用者发现很难抑制自己的行为,特别是当工作记忆需求增加时,先前已表明在提示诱发的对药物的渴望期间工作记忆需求会增加。这些结果揭示了成瘾的这种执行功能障碍成分的神经解剖学基础,支持了认知功能可能在延长滥用或使使用者易复发方面发挥的重要作用。