The Role Of The Left Middle Frontal Gyrus In Reading Chinese Characters

The writing system of Chinese characters is different from the pinyin writing system in its special properties.Different from the linear arrangement of pinyin characters,Chinese characters have complex spatial structure,which requires more processing of visual spatial working memory in the reading of Chinese characters.In contrast,reading Chinese characters requires more activation of the left middle frontal gyrus(MFG)region of the brain,which is thought to be a reading mechanism specific to Chinese characters,than reading pinyin.However,with the discovery of more studies,the function of MFG in Chinese character reading has been questioned,mainly because some researchers found that its function may be related to phonetic and semantic processing.Thus,whether the unique activation of MFG in Chinese reading corresponds to the spatial working memory of glyphs has not been unified.In this study,functional near-infrared brain imaging(fNIRS)technology was used to reveal the role of MFG in Chinese character reading,aiming at the activation of MFG on the left side of the brain.The experiment manipulated both the stimulus material and the working memory load.The repeated measurement experiment design of 2(materials:Chinese characters and pictures)×2(working memory load:1-back,2-back)was used.Meanwhile,the behavioral data and fNIRS data of 30 college students whose native language was Chinese were collected to explore the role of the left middle frontal gyrus in the reading of Chinese characters.The results showed that the subjects' response time had significant main effects on both the stimulus material and the task type.The subjects' response time on the Chinese material was significantly slower than that on the picture material,and the response time on the 2-back task with greater working memory load was slower than that on the low-load 1-back task.The results of fNIRS found that the activation intensity of the left MFG to Chinese characters was stronger than the picture,indicating that the left MFG was involved in the processing of Chinese characters.Moreover,the activation of MFG showed significant interaction between material type and task type,because the activation intensity of MFG on Chinese material was greater than that of picture material under the low-load 1-back task,indicating that working memory load affected the role of left middle frontal gyrus in Chinese reading.Therefore,in this study,it was found from the behavioral results and the activation results of fNIRS brain area that the activation of MFG was indeed different from that of picture materials for Chinese character processing,and this activation was affected by the working memory load,indicating that the function of this brain area in Chinese character reading may be related to the processing of glyph working memory.