Objective: The objective of this study was to implement convenient, fast, and accurate Mandarin task paradigms for functional MRI, and to locate the Chinese language functional areas in frontal and temporal lobes.
Materials and methods: Nineteen healthy Chinese volunteers participated in this study, which utilized a block design with four language tasks: auditory naming (AN), picture naming (PN), verbal fluency-character (VFC), and verbal fluency-letter (VFL). All functional images were preprocessed by SPM 8, followed by first- and second-level analyses and lateralization index calculation.
Results: Group analyses showed that for AN and PN, maximal responses were located in the right superior temporal gyrus. The picture naming-scrambled pictures and faces contrast gave maximal responses in the left fusiform gyrus; VFC in the left middle frontal gyrus and the left superior frontal gyrus. For VFL the maximal response was in the left superior temporal gyrus. There was some inconsistency of activations for individual subjects. At a threshold of Z > 2.5, 10 voxels extent, activations were seen in >50% subjects for AN in the right superior temporal gyrus, the right middle frontal gyrus, and the left middle temporal gyrus, for PN in the right superior temporal gyrus and for picture naming-scrambled pictures and faces in left inferior frontal gyrus. As a group, the lateralization index of all contrasts were left hemisphere dominant in the frontal lobes. In the temporal lobe, the hemispheric dominance differed for different contrasts.
Conclusion: These Chinese language stimulus paradigms activated language areas, and the functional regions of brain in different language tasks, and can now be piloted in clinical studies.
Keywords: Chinese; bold fMRI; brain function; language stimulus pattern; lateralization index.