Schacht Annekathrin, Sommer Werner
Humboldt University at Berlin, Berlin, Germany.
Cogn Affect Behav Neurosci. 2009 Mar;9(1):28-43. doi: 10.3758/CABN.9.1.28.
The emotional content of stimuli influences cognitive performance. In two experiments, we investigated the time course and mechanisms of emotional influences on visual word processing in various tasks by recording event-related brain potentials (ERPs). The stimuli were verbs of positive, negative, and neutral valence. In Experiment 1, where lexical decisions had to be performed on single verbs, both positive and negative verbs were processed more quickly than neutral verbs and elicited a distinct ERP component, starting around 370 msec. In Experiment 2, the verbs were embedded in a semantic context provided by single nouns. Likewise, structural, lexical, and semantic decisions for positive verbs were accelerated, and an ERP effect with a scalp distribution comparable to that in Experiment 1 now started about 200 msec earlier. These effects may signal an automatic allocation of attentional resources to emotionally arousing words, since they were not modulated by different task demands. In contrast, a later ERP effect of emotion was restricted to lexical and semantic decisions and, thus, appears to indicate more elaborated, task-dependent processing of emotional words.
刺激的情感内容会影响认知表现。在两项实验中，我们通过记录事件相关脑电位（ERP），研究了情感在各种任务中对视觉单词处理产生影响的时间进程和机制。刺激物是具有正性、负性和中性效价的动词。在实验1中，需要对单个动词进行词汇判断，结果发现正性和负性动词的处理速度都比中性动词更快，并且引发了一个独特的ERP成分，大约在370毫秒左右开始出现。在实验2中，动词被嵌入到由单个名词提供的语义情境中。同样，对正性动词的结构、词汇和语义判断也加快了，并且现在一个头皮分布与实验1中类似的ERP效应大约提前200毫秒开始出现。这些效应可能表明注意力资源会自动分配到引起情感反应的单词上，因为它们不受不同任务要求的调节。相比之下，后期的情感ERP效应仅限于词汇和语义判断，因此似乎表明对情感单词的处理更加精细、依赖于任务。
