英国一项最新研究说，对毒品可卡因上瘾者大脑中某些功能性结构会存在异常，这项研究或许有助于找到戒除毒瘾的方法。
英国剑桥大学研究人员在新一期学术刊物《脑》上报告说，他们利用磁共振成像仪扫描了６０名可卡因上瘾者的大脑，然后与另６０名普通人的大脑进行对比，结果发现，可卡因上瘾者大脑中的眼窝前额皮质等部位的灰质明显较少。
大脑灰质是神经元密集的地方。眼窝前额皮质等部位的灰质与人作决定的能力有关。这些部位的灰质较少，作决定能力差，可能正是上瘾者难以痛下决心戒掉毒瘾的原因。
与此相对的是，研究还发现可卡因上瘾者大脑中尾状核等部位的灰质较多，这些部位的灰质与大脑的奖励回馈机制有关。这一地区的功能强大意味着，上瘾者从吸食可卡因中获得的快感会比一般人大。
研究人员卡伦·埃尔施说，分析显示毒瘾越大，瘾君子大脑中这些部位的异常程度也就越高。目前需要进一步研究来证实，是吸食可卡因造成了大脑结构异常，还是大脑结构原本就有异常者更易上瘾。（生物谷Bioon.com）
生物谷推荐原文出处：
Brain DOI: 10.1093/brain/awr138
Abnormal structure of frontostriatal brain systems is associated with aspects of impulsivity and compulsivity in cocaine dependence
Karen D. Ersche, Anna Barnes, P. Simon Jones, Sharon Morein-Zamir, Trevor W. Robbins and Edward T. Bullmore
A growing body of preclinical evidence indicates that addiction to cocaine is associated with neuroadaptive changes in frontostriatal brain systems. Human studies in cocaine-dependent individuals have shown alterations in brain structure, but it is less clear how these changes may be related to the clinical phenotype of cocaine dependence characterized by impulsive behaviours and compulsive drug-taking. Here we compared self-report, behavioural and structural magnetic resonance imaging data on a relatively large sample of cocaine-dependent individuals (n?=?60) with data on healthy volunteers (n?=?60); and we investigated the relationships between grey matter volume variation, duration of cocaine use, and measures of impulsivity and compulsivity in the cocaine-dependent group. Cocaine dependence was associated with an extensive system of abnormally decreased grey matter volume in orbitofrontal, cingulate, insular, temporoparietal and cerebellar cortex, and with a more localized increase in grey matter volume in the basal ganglia. Greater duration of cocaine dependence was correlated with greater grey matter volume reduction in orbitofrontal, cingulate and insular cortex. Greater impairment of attentional control was associated with reduced volume in insular cortex and increased volume of caudate nucleus. Greater compulsivity of drug use was associated with reduced volume in orbitofrontal cortex. Cocaine-dependent individuals had abnormal structure of corticostriatal systems, and variability in the extent of anatomical changes in orbitofrontal, insular and striatal structures was related to individual differences in duration of dependence, inattention and compulsivity of cocaine consumption.
