Strijkers Kristof, Bertrand Daisy, Grainger Jonathan
CNRS, Aix-en-Provence, France.
Université d'Aix-Marseille, Marseille, France.
J Cogn Neurosci. 2015 Aug;27(8):1542-51. doi: 10.1162/jocn_a_00797. Epub 2015 Mar 11.
We investigated how linguistic intention affects the time course of visual word recognition by comparing the brain's electrophysiological response to a word's lexical frequency, a well-established psycholinguistic marker of lexical access, when participants actively retrieve the meaning of the written input (semantic categorization) versus a situation where no language processing is necessary (ink color categorization). In the semantic task, the ERPs elicited by high-frequency words started to diverge from those elicited by low-frequency words as early as 120 msec after stimulus onset. On the other hand, when categorizing the colored font of the very same words in the color task, word frequency did not modulate ERPs until some 100 msec later (220 msec poststimulus onset) and did so for a shorter period and with a smaller scalp distribution. The results demonstrate that, although written words indeed elicit automatic recognition processes in the brain, the speed and quality of lexical processing critically depends on the top-down intention to engage in a linguistic task.
我们通过比较大脑对单词词频（一种公认的词汇通达心理语言学指标）的电生理反应，研究了语言意图如何影响视觉单词识别的时间进程。当参与者积极检索书面输入的含义（语义分类）时，与不需要语言处理的情况（墨水颜色分类）相比。在语义任务中，高频词引发的事件相关电位（ERP）在刺激开始后120毫秒就开始与低频词引发的ERP出现差异。另一方面，在颜色任务中对相同单词的彩色字体进行分类时，词频直到大约100毫秒后（刺激开始后220毫秒）才调节ERP，并且调节的时间较短，头皮分布范围较小。结果表明，虽然书面单词确实会在大脑中引发自动识别过程，但词汇处理的速度和质量关键取决于参与语言任务的自上而下的意图。
