Bailey Kira, Amlung Michael T, Morris David H, Price Mason H, Von Gunten Curtis, McCarthy Denis M, Bartholow Bruce D
Department of Psychological Sciences, University of Missouri, 210 McAlester Hall, Columbia, MO, 65211, USA.
Midwest Alcoholism Research Center, Columbia, MO, USA.
Psychopharmacology (Berl). 2016 Apr;233(7):1245-55. doi: 10.1007/s00213-016-4208-y. Epub 2016 Jan 27.
Caffeine is commonly believed to offset the acute effects of alcohol, but some evidence suggests that cognitive processes remain impaired when caffeine and alcohol are coadministered.
No previous study has investigated the separate and joint effects of alcohol and caffeine on conflict monitoring and adaptation, processes thought to be critical for self-regulation. This was the purpose of the current study.
Healthy, young adult social drinkers recruited from the community completed a flanker task after consuming one of four beverages in a 2 × 2 experimental design: Alcohol + caffeine, alcohol + placebo caffeine, placebo alcohol + caffeine, or placebo alcohol + placebo caffeine. Accuracy, response time, and the amplitude of the N2 component of the event-related potential (ERP), a neural index of conflict monitoring, were examined as a function of whether or not conflict was present (i.e., whether or not flankers were compatible with the target) on both the previous trial and the current trial.
Alcohol did not abolish conflict monitoring or adaptation. Caffeine eliminated conflict adaptation in sequential trials but also enhanced neural conflict monitoring. The combined effect of alcohol and caffeine was apparent only in how previous conflict affected the neural conflict monitoring response.
Together, the findings suggest that caffeine leads to exaggeration of attentional resource utilization, which could provide short-term benefits but lead to problems conserving resources for when they are most needed.
人们普遍认为咖啡因可以抵消酒精的急性影响，但一些证据表明，同时摄入咖啡因和酒精时认知过程仍会受损。
此前尚无研究调查酒精和咖啡因对冲突监测与适应的单独及联合影响，而冲突监测与适应被认为是自我调节的关键过程。本研究旨在探究此问题。
从社区招募健康的年轻成年社交饮酒者，采用2×2实验设计，让他们在饮用四种饮料之一后完成一项侧翼任务：酒精+咖啡因、酒精+安慰剂咖啡因、安慰剂酒精+咖啡因或安慰剂酒精+安慰剂咖啡因。根据前一次试验和当前试验中是否存在冲突（即侧翼刺激与目标是否一致），检查准确性、反应时间以及事件相关电位（ERP）中N2成分的幅值（冲突监测的神经指标）。
酒精并未消除冲突监测或适应。咖啡因消除了连续试验中的冲突适应，但也增强了神经冲突监测。酒精和咖啡因的联合效应仅在先前冲突如何影响神经冲突监测反应方面明显。
这些研究结果共同表明，咖啡因会导致注意力资源利用过度，这可能带来短期益处，但在最需要资源时会导致资源保存问题。
