McCarthy G, Nobre A C
Neuropsychology Laboratory, VA Medical Center, West Haven, CT 06516.
Electroencephalogr Clin Neurophysiol. 1993 May-Jun;88(3):210-9. doi: 10.1016/0168-5597(93)90005-a.
The effects of spatial selective attention upon ERPs associated with the processing of word stimuli were investigated. While subjects maintained central eye fixation, ERPs were recorded to words presented to the left and right visual fields. In each of 6 runs, subjects focussed attention to alternate fields to perform a category-detection task. Pairs of semantically related and repeated words were embedded in the word lists presented to the attended and unattended visual fields. Consistent with prior studies, the P1-N1 visual ERP was larger when elicited by words in attended spatial locations. A large negative slow wave identified as N400 was elicited by attended, but not unattended, words. For attended words, N400 was smaller for semantically primed or repeated words. We concluded that spatial selective attention can modulate the degree to which words are processed, and that the cognitive processes associated with N400 are not automatic.
研究了空间选择性注意对与单词刺激处理相关的事件相关电位（ERP）的影响。当受试者保持中央注视时，记录呈现给左、右视野单词的ERP。在6次试验的每次试验中，受试者将注意力集中在交替的视野上以执行类别检测任务。语义相关和重复的单词对被嵌入到呈现给被注意和未被注意视野的单词列表中。与先前的研究一致，当由被注意空间位置的单词引发时，P1-N1视觉ERP更大。一个被识别为N400的大的负向慢波由被注意的单词而非未被注意的单词引发。对于被注意的单词，语义启动或重复的单词引发的N400较小。我们得出结论，空间选择性注意可以调节单词的处理程度，并且与N400相关的认知过程不是自动的。
