Neural Correlates of the Perception of Lexical Levels in English

다국어 초록 (Multilingual Abstract)

The primary aim of the present study is to explore the relationship between derivation levels and neural patterns by investigating how level 1 and level 2 derivational forms are processed in the brain using functional Magnetic Resonance Imaging (fMRI) technology. During an auditory discrimination task, more of the left inferior frontal gyrus (IFG) and the left posterior superior temporal gyrus (STG) were involved in the perception of level 2 words relative to level 1 words, with none of the areas activated for the level 1 vs. level 2 contrast
although the left STG was activated for the level 1 vs. nonspeech comparison. These results show that level 2 words are perceived through a morphological/rule-based analysis of their stem + affix structure, whereas level 1 words are stored and retrieved as a whole, consistent with the “dual-system” (DS) theory postulating two distinct systems in charge of the perception of regular and irregular inflections. Additionally, the contrast analysis of each speech condition relative to nonspeech baseline elicits stronger effects in the left posterior STG, the left premotor area, the left supramarginal gyrus, and the bilateral middle temporal gyrus, which confirms a common speech perception network as revealed by previous neuroimaging studies on speech perception.