Katayama J, Polich J
Faculty of Education, Hokkaido University, Sapporo, Japan.
Psychophysiology. 1998 Jan;35(1):23-33.
P300 differences for target (.10), nontarget (.10), and standard tones (.80) were assessed using a three-stimulus oddball paradigm in which participants responded only to the target (n = 12). Target/standard (easy or difficult) and nontarget/standard (large or small) pitch differences were manipulated orthogonally. In all conditions, target tones elicited a parietal P300, which was affected only by the target/standard discrimination ease. Nontarget in the easy/large and difficult/small conditions elicited a parietal but smaller P300 than the target but in the easy/small condition elicited similar ERPs to the standard. However, nontarget stimuli in the difficult/large condition elicited an anterior maximum and earlier P300 (P3a) component. The findings suggest that target P300s are not influenced by the nontarget stimulus configuration, whereas the nontarget P300 outcomes are determined directly by the stimulus context. The theoretical implications are discussed.
使用三刺激Oddball范式评估目标音（.10）、非目标音（.10）和标准音（.80）的P300差异，其中参与者仅对目标音做出反应（n = 12）。目标音/标准音（容易或困难）和非目标音/标准音（大或小）的音高差异被正交操纵。在所有条件下，目标音诱发顶叶P300，其仅受目标音/标准音辨别难易程度的影响。在容易/大差异和困难/小差异条件下的非目标音诱发顶叶P300，但比目标音诱发的P300小，而在容易/小差异条件下诱发的事件相关电位与标准音相似。然而，在困难/大差异条件下的非目标刺激诱发了前部最大且更早的P300（P3a）成分。研究结果表明，目标P300不受非目标刺激配置的影响，而非目标P300结果直接由刺激背景决定。讨论了其理论意义。
