Marinkovic Ksenija, Halgren Eric, Maltzman Irving
Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA.
Alcohol Clin Exp Res. 2004 Mar;28(3):415-23. doi: 10.1097/01.alc.0000117828.88597.80.
Behavioral studies suggest that alcohol intoxication impairs the speed and accuracy of word recognition and categorization, but alcohol's effects on the brain during verbal cognitive processing are not adequately understood. Using event-related potentials (ERP) and a word-recognition paradigm, this study investigated the effects of alcohol intoxication on prelexical, semantic, and mnemonic aspects of verbal processing.
Concurrent measures of ERPs and skin conductance responses were obtained in a word-repetition priming task and permitted a comparison of the effects of alcohol on the central and autonomic physiologic systems. Social drinkers participated in all four cells of the within-subjects balanced placebo design, in which the effects of alcohol and information as to the beverage content (expectancy) were manipulated. The average peak blood alcohol level peaked at 0.045%.
None of the manipulations affected behavioral performance, and expectancy had no effect on any of the measures. In contrast, alcohol ingestion attenuated the temporoparietal N180, suggesting an impairment in prelexical pattern-recognition processes. Alcohol significantly increased the amplitude of N450 and the latency of P580, particularly on trials evoking sympathetic arousal as measured with skin conductance responses.
Although behavioral measures were unaffected, ERPs showed that a moderately low alcohol dose affected verbal processing during both early, prelexical and late, semantic stages. Alcohol significantly increased the difficulty of semantic access and integration, as reflected in larger N450 amplitude and longer P580 latency. This effect was particularly prominent on arousal-related trials, suggesting that alcohol impairs processes that modulate cognitive functioning. The lack of an interaction between the factors of repetition and beverage suggests that a moderately low alcohol dose exerts these effects via the semantic and integration systems rather than via memory processes.
行为学研究表明，酒精中毒会损害单词识别和分类的速度与准确性，但人们对酒精在言语认知加工过程中对大脑的影响尚未有充分的了解。本研究采用事件相关电位（ERP）和单词识别范式，探究了酒精中毒对言语加工的词前、语义和记忆方面的影响。
在单词重复启动任务中同步测量ERP和皮肤电导率反应，从而比较酒精对中枢和自主生理系统的影响。社交饮酒者参与了被试内平衡安慰剂设计的所有四个单元格，其中对酒精的影响以及关于饮料成分的信息（预期）进行了操控。平均血酒精浓度峰值为0.045%。
所有操控均未影响行为表现，预期对任何测量指标均无影响。相比之下，摄入酒精会减弱颞顶叶N180，表明词前模式识别过程受损。酒精显著增加了N450的波幅和P580的潜伏期，尤其是在通过皮肤电导率反应测量出诱发交感神经兴奋的试验中。
尽管行为测量未受影响，但ERP显示，适度低剂量的酒精会在早期词前和晚期语义阶段影响言语加工。酒精显著增加了语义通达和整合的难度，这体现在更大的N450波幅和更长的P580潜伏期上。这种效应在与兴奋相关的试验中尤为突出，表明酒精会损害调节认知功能的过程。重复因素与饮料因素之间缺乏交互作用，表明适度低剂量的酒精是通过语义和整合系统而非记忆过程产生这些影响的。
