Nagy M E, Rugg M D
Psychophysiology. 1989 Jul;26(4):431-6. doi: 10.1111/j.1469-8986.1989.tb01946.x.
The modulation of event-related potentials by word repetition was investigated in two experiments. In both experiments, subjects responded to occasional nonwords interspersed among a series of words. A proportion of the words were repetitions of previously presented items. Words were repeated after 0 or 6 intervening items in Experiment 1 and after 6 or 19 items in Experiment 2. Event-related potentials to repeated words were characterised by a sustained, widespread positive-going shift with an onset of approximately 300 ms. This effect did not vary significantly as a function of lag in either experiment. When words were repeated immediately, this repetition-evoked positive shift was preceded by a transient negative deflection (onset ca. 200 ms) which was absent in event-related potentials to words repeated at longer lags. These results suggest that the modulation of event-related potentials by word repetition is influenced by at least two processes. One of these processes acts relatively early during the processing of a repeated word, but subsides rapidly as inter-item lag between first and second presentations increases. The second process occurs later in time, but is considerably more robust over variations in inter-item lag.
在两个实验中研究了词重复对事件相关电位的调节作用。在两个实验中，受试者对穿插在一系列单词中的偶尔出现的非单词做出反应。一部分单词是先前呈现项目的重复。在实验1中，单词在0个或6个间隔项目后重复，在实验2中，单词在6个或19个项目后重复。对重复单词的事件相关电位的特征是持续的、广泛的正向偏移，起始时间约为300毫秒。在两个实验中，这种效应作为间隔时间的函数没有显著变化。当单词立即重复时，这种重复诱发的正向偏移之前有一个短暂的负向偏转（起始时间约为200毫秒），而在较长间隔时间重复的单词的事件相关电位中不存在这种负向偏转。这些结果表明，词重复对事件相关电位的调节至少受两个过程的影响。其中一个过程在重复单词的处理过程中相对较早起作用，但随着第一次和第二次呈现之间的项目间隔增加而迅速消退。第二个过程在时间上较晚出现，但在项目间隔变化方面更稳健。
