Finn P R, Justus A, Mazas C, Steinmetz J E
Department of Psychology, Indiana University, 1101 E. 10th Street, Bloomington, IN 47405-7007, USA.
Psychopharmacology (Berl). 1999 Oct;146(4):465-72. doi: 10.1007/pl00005492.
Impulsivity is associated with increased risk for alcoholism. Alcohol also may increase impulsive behavior, although little is known about the processes underlying this effect.
This study tested a model proposing that the executive processes of working memory (WM) and conditional associative learning (CAL) modulate behavioral inhibition. Subjects had either a positive (FHP) or a negative (FHN) family history of alcoholism. Hypotheses were that alcohol would increase Go/No-Go impulsive responding but only in subjects with low working memory capacity (low-WM), low-CAL ability, or FHP for alcoholism. The model also predicted that WM and CAL modulate inhibitory responses to contingency reversal on a Go/No-Go task.
A Go/No-Go learning task with a midway contingency reversal was administered to 71 FHP and 78 FHN subjects when sober and after drinking one of two moderate doses of alcohol. WM (digits backward) and CAL (conditional spatial association task) were also assessed when sober.
Alcohol resulted in more false alarms but only in low-WM subjects. Both WM and CAL modulated learning to inhibit behavior after contingency reversal, suggesting separate modulation mechanisms for WM and CAL. Subjects with low- capacity WM and subjects with low-capacity CAL ability had more difficulty learning response inhibition after contingency reversal. FHPs and FHNs did not differ in their response to alcohol.
The results support our model of the modulatory role of WM and CAL in the ongoing regulation of behavioral inhibitory systems. The results also suggest that individuals with low capacity WM are more susceptible to alcohol's effect of increasing impulsive behavior, suggesting that alcohol reduces the capacity of working memory to modulate response inhibition.
冲动性与酒精成瘾风险增加有关。酒精也可能会增加冲动行为，尽管对这种效应背后的机制知之甚少。
本研究测试了一个模型，该模型提出工作记忆（WM）和条件联想学习（CAL）的执行过程调节行为抑制。受试者有酒精成瘾的阳性（FHP）或阴性（FHN）家族史。假设是酒精会增加“去/不去”冲动反应，但仅在工作记忆容量低（低WM）、CAL能力低或有酒精成瘾FHP的受试者中如此。该模型还预测，WM和CAL调节对“去/不去”任务中意外逆转的抑制反应。
对71名FHP和7名FHN受试者在清醒时以及饮用两种中等剂量酒精之一后，进行了带有中途意外逆转的“去/不去”学习任务。还在清醒时评估了WM（倒背数字）和CAL（条件空间联想任务）。
酒精导致更多误报，但仅在低WM受试者中如此。WM和CAL都调节了意外逆转后抑制行为的学习，表明WM和CAL有单独的调节机制。WM容量低的受试者和CAL能力低的受试者在意外逆转后学习反应抑制更困难。FHP和FHN对酒精的反应没有差异。
结果支持我们关于WM和CAL在行为抑制系统持续调节中的调节作用的模型。结果还表明，WM容量低的个体更容易受到酒精增加冲动行为效应的影响，这表明酒精降低了工作记忆调节反应抑制的能力。
