Irimia Cristina, Wiskerke Joost, Natividad Luis A, Polis Ilham Y, de Vries Taco J, Pattij Tommy, Parsons Loren H
Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, USA.
Addict Biol. 2015 Mar;20(2):263-74. doi: 10.1111/adb.12119. Epub 2013 Dec 17.
Impulsivity is a risk factor for alcoholism, and long-term alcohol exposure may further impair impulse control in a manner that propels problematic alcohol use. The present study employed the rat 5-choice serial reaction time task (5-CSRTT) to measure behavioral inhibition and attentional capacity during abstinence from repeated 5-day cycles of alcohol liquid diet consumption. Task performance was not disrupted following the first cycle of alcohol exposure; however, evidence of impaired behavioral inhibition emerged following the third cycle of alcohol exposure. In comparison with controls, alcoholic rats exhibited deficits in inhibitory control during cognitively challenging 5-CSRTT tests employing variable intertrial interval (varITI). This behavioral disruption was not present during early abstinence (3 days) but was evident by 7 days of abstinence and persisted for at least 34 days. Interestingly, renewed alcohol consumption ameliorated these disruptions in impulse control, although deficient behavioral inhibition re-emerged during subsequent abstinence. Indices of increased impulsivity were no longer present in tests conducted after 49 days of abstinence. Alcohol-related impairments in impulse control were not evident in sessions employing highly familiar task parameters regardless of the abstinence period, and control experiments confirmed that performance deficits during the challenge sessions were unlikely to result from alcohol-related disruption in the adaptation to repeated varITI testing. Together, the current findings demonstrate that chronic intermittent alcohol consumption results in decreased behavioral inhibition in rats that is temporally similar to clinical observations of disrupted impulsive control in abstinent alcoholics performing tasks of behavioral inhibition.
冲动性是酒精中毒的一个风险因素，长期接触酒精可能会进一步损害冲动控制，从而促使出现有问题的饮酒行为。本研究采用大鼠5选择连续反应时任务（5-CSRTT）来测量在经历5天周期的酒精液体饮食消费的重复过程后戒酒期间的行为抑制和注意力容量。在首次接触酒精的周期后，任务表现并未受到干扰；然而，在第三次接触酒精的周期后，出现了行为抑制受损的证据。与对照组相比，酒精成瘾大鼠在采用可变试次间隔（varITI）的具有认知挑战性的5-CSRTT测试中表现出抑制控制缺陷。这种行为干扰在早期戒酒（3天）期间不存在，但在戒酒7天时明显出现，并持续至少34天。有趣的是，重新饮酒改善了这些冲动控制方面的干扰，尽管在随后的戒酒期间又重新出现了行为抑制不足的情况。在戒酒49天后进行的测试中，冲动性增加的指标不再出现。无论戒酒期如何，在采用高度熟悉的任务参数的实验环节中，与酒精相关的冲动控制损害并不明显，对照实验证实，在具有挑战性的实验环节中的表现缺陷不太可能是由于适应重复的varITI测试过程中与酒精相关的干扰所致。总之，目前的研究结果表明，慢性间歇性酒精消费会导致大鼠行为抑制能力下降，这在时间上与临床观察到的戒酒酒精成瘾者在执行行为抑制任务时冲动控制受到干扰的情况相似。
