英國一項(xiàng)最新研究說,,對毒品可卡因上癮者大腦中某些功能性結(jié)構(gòu)會(huì)存在異常,,這項(xiàng)研究或許有助于找到戒除毒癮的方法。
英國劍橋大學(xué)研究人員在新一期學(xué)術(shù)刊物《腦》上報(bào)告說,,他們利用磁共振成像儀掃描了60名可卡因上癮者的大腦,,然后與另60名普通人的大腦進(jìn)行對比,結(jié)果發(fā)現(xiàn),,可卡因上癮者大腦中的眼窩前額皮質(zhì)等部位的灰質(zhì)明顯較少,。
大腦灰質(zhì)是神經(jīng)元密集的地方。眼窩前額皮質(zhì)等部位的灰質(zhì)與人作決定的能力有關(guān),。這些部位的灰質(zhì)較少,,作決定能力差,可能正是上癮者難以痛下決心戒掉毒癮的原因,。
與此相對的是,,研究還發(fā)現(xiàn)可卡因上癮者大腦中尾狀核等部位的灰質(zhì)較多,這些部位的灰質(zhì)與大腦的獎(jiǎng)勵(lì)回饋機(jī)制有關(guān),。這一地區(qū)的功能強(qiáng)大意味著,,上癮者從吸食可卡因中獲得的快感會(huì)比一般人大。
研究人員卡倫·埃爾施說,,分析顯示毒癮越大,,癮君子大腦中這些部位的異常程度也就越高。目前需要進(jìn)一步研究來證實(shí),,是吸食可卡因造成了大腦結(jié)構(gòu)異常,,還是大腦結(jié)構(gòu)原本就有異常者更易上癮。(生物谷Bioon.com)
生物谷推薦原文出處:
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.