van Turennout M, Hagoort P, Brown C M
Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
J Exp Psychol Learn Mem Cogn. 1997 Jul;23(4):787-806. doi: 10.1037//0278-7393.23.4.787.
The temporal properties of semantic and phonological processes in speech production were investigated in a new experimental paradigm using movement-related brain potentials. The main experimental task was picture naming. In addition, a 2-choice reaction go/no-go procedure was included, involving a semantic and a phonological categorization of the picture name. Lateralized readiness potentials (LRPs) were derived to test whether semantic and phonological information activated motor processes at separate moments in time. An LRP was only observed on no-go trials when the semantic (not the phonological) decision determined the response hand. Varying the position of the critical phoneme in the picture name did not affect the onset of the LRP but rather influenced when the LRP began to differ on go and no-go trials and allowed the duration of phonological encoding of a word to be estimated. These results provide electrophysiological evidence for early semantic activation and later phonological encoding.
利用与运动相关的脑电活动，在一种新的实验范式中研究了言语产生中语义和语音过程的时间特性。主要实验任务是图片命名。此外，还纳入了一个二选一反应的执行/不执行程序，涉及图片名称的语义和语音分类。通过提取侧化准备电位（LRP）来测试语义和语音信息是否在不同时刻激活运动过程。仅在不执行试验中，当语义（而非语音）决策决定反应手时才观察到LRP。改变图片名称中关键音素的位置并不影响LRP的起始，但会影响LRP在执行和不执行试验中开始出现差异的时间，并可据此估计一个单词的语音编码持续时间。这些结果为早期语义激活和后期语音编码提供了电生理证据。
