Different activities on chinese character and figure processing by a Visual fMRI study involving literates and illiterates

Functional magnetic resonance imaging (fMRI) or positron emission tomography (PET) proved different brain activation patterns in processing Chinese and alphabetic languages. Previous studies that have compared performance between alphabetic literate and illiterate subjects, indicate that the literates surpass die illiterates especially in tasks involving phonological processing and that different activation regions in fMRI locate between Broca's area and the inferior parietal cortex as well as the posteriormidinsula bridge between Wernicke's and Broca's area. Few such studies were about Chinese-speaking individuals except one which showed different activation patterns between Chinese illiterates and literates in silent word recognition task (the left inferior/middle frontal gyrus and bilateral superior temporal gyri) and in silent picture-naming task (the bilateral inferior/middle fontal gyri and left limbic cingulated gyrus). However, sheer residual activations after direct comparison of literates to illiterates through different tasks remain to be further clarified. In this study, we used fMRI to examine the comparative difference of brain activations by simple visual character and figure tasks in 26 healthy right-handed Chinese subjects (13 illiterates and 13 literates). After comparison of the literate group to the illiterate, we observed: different activation regions in the Chinese character discrimination task involve the bilateral superior temporal gyrus (BA39/40), the left middle frontal gyrus (BA9/10), the left middle temporal gyrus (BA20), the bilateral middle temporal gyrus (BA21), the bilateral superior temporal gyrus (BA22), dorsal posterior cingualte (BA23/31) and cerebellum; in the simple figure discrimination task, different activations occur in the left percuneus (BA7), the bilateral superior gyrus (BA39), the left inferior frontal gyrus (BA44), the left middle temporal gyrus (BA21), the left middle occipital gyrus (BA19), the left superior longitudinal fascicule (BA4), dorsal posterior cingualte (BA23/31) and cerebellum. We conclude that literates, compared to illiterates, have intenser activations when discriminating Chinese characters and figures by a visual input modality.