Bell Ryan P, Garavan Hugh, Foxe John J
The Sheryl and Daniel R. Tishman Cognitive Neurophysiology Laboratory, Children's Evaluation and Rehabilitation Center (CERC), Department of Pediatrics, Albert Einstein College of Medicine & Montefiore Medical Center, Van Etten Building - Wing 1C, 1300 Morris Park Avenue, Bronx, NY 10461, USA; Program in Cognitive Neuroscience, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, NY 10016, USA.
University of Vermont, Department of Psychiatry, 1 South Prospect St, Burlington, VT 05401, USA; The Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA.
Neuropharmacology. 2014 Oct;85:461-70. doi: 10.1016/j.neuropharm.2014.05.011. Epub 2014 Jun 18.
A significant hindrance to effective treatment of addiction is identifying those most likely to relapse. Cocaine addiction is characterized by deficits in inhibitory control and elevated reactivity to cocaine cues, both hypothesized to be integral to development of addiction and propensity to relapse. It follows that reduction of both impulsivity and cue-reactivity following abstinence is protective against relapse, and that persistence of these factors increases vulnerability. Using functional magnetic resonance imaging, we examined neural activation patterns in dorsal and ventral striatum in abstinent cocaine dependent (CD) individuals (N=20) and non-using controls (N=19) as they performed a cocaine craving task. We also examined activations in nodes of the response inhibition circuit (RIC) as they performed an inhibition task. At the between-groups level, no differences in RIC or striatal activation were seen in former users, in contrast to previous investigations in current users, suggesting large-scale functional recovery with abstinence. However, at the individual participant-level, abstinent CD individuals displayed an association between cocaine cue-related neural activations in the right ventral striatum and compulsive cocaine craving scores. Compulsive craving scores were also negatively correlated with duration of abstinence. Further, there was an association between motor impulsivity scores and inhibition-related activations in the right inferior frontal gyrus and pre-supplementary motor area in abstinent CD individuals. Thus, while former users as a group did not show deficits in inhibitory function or cocaine-cue reactivity, participant-level results pointed to activation patterns in a minority of these individuals that likely contributes to enduring relapse vulnerability.
有效治疗成瘾的一个重大障碍是识别那些最有可能复发的人。可卡因成瘾的特征是抑制控制能力缺陷以及对可卡因线索的反应性增强,这两者都被认为是成瘾发展和复发倾向的重要因素。因此,戒断后冲动性和线索反应性的降低可预防复发,而这些因素的持续存在会增加易感性。我们使用功能磁共振成像,在戒断的可卡因依赖(CD)个体(N = 20)和非使用对照组(N = 19)执行可卡因渴望任务时,检查了背侧和腹侧纹状体的神经激活模式。我们还在他们执行抑制任务时检查了反应抑制回路(RIC)节点的激活情况。在组间水平上,与之前对当前使用者的研究相比,在以前的使用者中未观察到RIC或纹状体激活的差异,这表明戒断后有大规模的功能恢复。然而,在个体参与者水平上,戒断的CD个体在右腹侧纹状体中显示出与可卡因线索相关的神经激活与强迫性可卡因渴望得分之间存在关联。强迫性渴望得分也与戒断持续时间呈负相关。此外,在戒断的CD个体中,运动冲动得分与右下额叶回和辅助运动前区的抑制相关激活之间存在关联。因此,虽然作为一个群体的以前使用者在抑制功能或可卡因线索反应性方面没有表现出缺陷,但参与者水平的结果指出了这些个体中少数人的激活模式,这可能导致持续的复发易感性。