Study Of Neural Mechanisms Of Chinese Words During The Resting State

Reading is a very important means of information acquisition and social communication. Neuroimaging researches have identified the word processing neural system, which includes distributed cerebral cortexes responding to the various linguistic attributes of word. In the recent years, studies of brain function during the resting state have become a hot point. In the present study, we have investigated the neural mechanisms of Chinese words processing during the resting state. Unlike the alphabetic words, Chinese character is a type of logographic writing word, which is composed of a number of strokes and requires fine-gained visual spatial processing. Chinese words become a valuable research object in cognitive neuroscience. In the present study, we used fMRI technology and employed Chinese words as stimuli to study neural mechanisms of Chinese words during the resting state. The primary work and contributions are listed as follows: First, during the resting state, we compared children (age:10-11) and adults (age:20-25) to investigate the intrinsic organized Chinese words processing network. Functional connectivity (FC) and amplitude of low frequency fluctuations (ALFF) were performed. FC results demonstrated that the Chinese words processing network of children during the resting state were largely similar with the adults’. By the3-4years’ educations, children have developed an adult-like Chinese words processing network. ALFF results illustrated that, compared to adults, children used more reading-irrelevant neural systems. Although children developed an adult-like Chinese words processing network during the resting state, children still need further development.Second, we know that there exists an intrinsic organized Chinese word processing network during the resting state. Then, is there information flows between the brain regions? So, Granger causality approach (GCA) was performed to analyze five brain regions which were related to Chinese words processing. These brain regions were the left superior parietal lobule (SPL), the left supramarginal gyrus, the left middle frontal gyrus (MFG), visual word form area (VWFA), and the right fusiform gyrus. These results demonstrated the intercommunications among the brain regions which responded to the visual processing of Chinese words without any explicit tasks, and further indicated a preparatory brain networks for the highly probable words input during the resting state. Third, we used functional connectivity to study the sex differences within the Chinese words processing network during the resting state. The results demonstrated that when compared females to males, the bilateral lingual gyrus (BA17/18) and the right inferior occipital gyrus (BA17) showed higher functional connectivity, and, when compared males to females, some brain regions showed higher functional connectivity, including the right cingulated gyrus (BA10), the right superior frontal gyrus (BA10), and the right inferior frontal gyrus (BA9/45). FC results revealed that although there are similar Chinese words processing network between females and males during the resting state, some differences existed.In the present study, during the resting state, we studied Chinese words processing neural mechanisms from several aspects. Our findings provide new evidences for the understanding of words processing mechanisms.