Substance Dependence Division, Psychiatry Department, University of Colorado Denver, Denver, Colorado, USA.
PLoS One. 2010 Sep 22;5(9):e12835. doi: 10.1371/journal.pone.0012835.
Adolescents with conduct and substance problems ("Antisocial Substance Disorder" (ASD)) repeatedly engage in risky antisocial and drug-using behaviors. We hypothesized that, during processing of risky decisions and resulting rewards and punishments, brain activation would differ between abstinent ASD boys and comparison boys.
METHODOLOGY/PRINCIPAL FINDINGS: We compared 20 abstinent adolescent male patients in treatment for ASD with 20 community controls, examining rapid event-related blood-oxygen-level-dependent (BOLD) responses during functional magnetic resonance imaging. In 90 decision trials participants chose to make either a cautious response that earned one cent, or a risky response that would either gain 5 cents or lose 10 cents; odds of losing increased as the game progressed. We also examined those times when subjects experienced wins, or separately losses, from their risky choices. We contrasted decision trials against very similar comparison trials requiring no decisions, using whole-brain BOLD-response analyses of group differences, corrected for multiple comparisons. During decision-making ASD boys showed hypoactivation in numerous brain regions robustly activated by controls, including orbitofrontal and dorsolateral prefrontal cortices, anterior cingulate, basal ganglia, insula, amygdala, hippocampus, and cerebellum. While experiencing wins, ASD boys had significantly less activity than controls in anterior cingulate, temporal regions, and cerebellum, with more activity nowhere. During losses ASD boys had significantly more activity than controls in orbitofrontal cortex, dorsolateral prefrontal cortex, brain stem, and cerebellum, with less activity nowhere.
CONCLUSIONS/SIGNIFICANCE: Adolescent boys with ASD had extensive neural hypoactivity during risky decision-making, coupled with decreased activity during reward and increased activity during loss. These neural patterns may underlie the dangerous, excessive, sustained risk-taking of such boys. The findings suggest that the dysphoria, reward insensitivity, and suppressed neural activity observed among older addicted persons also characterize youths early in the development of substance use disorders.
有行为和物质问题的青少年(“反社会物质障碍”(ASD))反复从事危险的反社会和吸毒行为。我们假设,在处理风险决策以及由此产生的奖励和惩罚时,禁欲 ASD 男孩和对照组男孩的大脑激活会有所不同。
方法/主要发现:我们比较了 20 名接受 ASD 治疗的禁欲青少年男性患者和 20 名社区对照组,检查了功能磁共振成像过程中快速事件相关血氧水平依赖(BOLD)反应。在 90 次决策试验中,参与者选择做出谨慎反应,赚取一分钱,或者冒险反应,赚取五分或损失 10 分钱;随着游戏的进行,损失的几率增加。我们还检查了受试者从冒险选择中获得收益或分别损失的那些时间。我们使用全脑 BOLD 反应分析,对群体差异进行比较,以校正多次比较,将决策试验与不需要决策的非常相似的对照试验进行对比。在决策过程中,ASD 男孩表现出许多大脑区域的活动不足,这些区域被对照组强烈激活,包括眶额和背外侧前额叶皮层、前扣带、基底神经节、岛叶、杏仁核、海马体和小脑。当体验到收益时,与对照组相比,ASD 男孩的前扣带、颞叶区域和小脑的活动明显减少,而无处增加活动。在损失期间,与对照组相比,ASD 男孩的眶额皮层、背外侧前额叶皮层、脑干和小脑的活动明显增加,而无处减少活动。
结论/意义:患有 ASD 的青少年在进行冒险决策时大脑活动广泛不足,同时在奖励时活动减少,在损失时活动增加。这些神经模式可能是这些男孩危险、过度、持续冒险行为的基础。这些发现表明,在老年成瘾者中观察到的抑郁、奖励不敏感和抑制性神经活动也存在于物质使用障碍早期发展的青少年中。