Sysoeva Olga V, Ilyuchenok Inna R, Ivanitsky Alexey M
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 5a Butlerova street, Moscow 117485, Russia.
Int J Psychophysiol. 2007 Sep;65(3):272-83. doi: 10.1016/j.ijpsycho.2007.05.003. Epub 2007 May 17.
Previous studies have repeatedly found that late (300-800 ms) components of event-related potentials (ERP) reflected semantic analysis, i.e. the differentiation between abstract and concrete words. However, the human brain may detect the meaning of the words much earlier. This study investigated the brain mechanisms of the processing of abstract and concrete written words in four experimental conditions: i) Simple Reading, during which volunteers were required to silently read words; ii) Simple Classification, during which volunteers were required to classify the presented word into the abstract and concrete categories; and iii) Cued and iv) Uncued Selective Classification conditions, during which subjects had to classify only the words typed in a particular colour. 19-channel EEG was recorded during the experiment from 13 subjects. The ERP to abstract and concrete words differed not only at the late but also at early (40-100 ms) latencies in the Simple Reading and Classification conditions, as well as for the words that should not be explicitly classified in the Cued Selective Classification condition. This means that semantic analysis can occur in a manner which is both very rapid and implicit. Moreover, increasing task demands can even suppress this rapid semantic analysis. The functional microstate analysis revealed a topographical difference in response to abstract and concrete words, which indicated that at least partly distinct brain networks are involved in the processing of words during both early (implicit differentiation) and late (explicit classification) latencies.
以往的研究反复发现，事件相关电位（ERP）的晚期成分（300 - 800毫秒）反映语义分析，即抽象词与具体词之间的区分。然而，人类大脑可能更早就能察觉到词语的含义。本研究在四种实验条件下探究了处理抽象和具体书面词语的脑机制：i）简单阅读，在此期间志愿者需默读词语；ii）简单分类，在此期间志愿者需将呈现的词语分类为抽象和具体类别；iii）提示性和iv）非提示性选择性分类条件，在此期间受试者必须仅对特定颜色输入的词语进行分类。实验期间从13名受试者记录了19通道脑电图。在简单阅读和分类条件下，以及在提示性选择性分类条件下不应明确分类的词语方面，抽象词和具体词的ERP不仅在晚期，而且在早期（40 - 100毫秒）潜伏期也存在差异。这意味着语义分析可以以非常快速且隐含的方式发生。此外，增加任务要求甚至可能抑制这种快速语义分析。功能微状态分析揭示了对抽象词和具体词反应的地形差异，这表明在早期（隐含区分）和晚期（明确分类）潜伏期处理词语时，至少部分不同的脑网络参与其中。
