| Objective: To explore the influence of semantic categories during naming task, and study the effects of life and nonlife picture naming tasks on the spatio temporal patterns of healthy brain activity. Methods: Ten healthy adult right handed subjects were enrolled. Twenty pictures from different semantic categories (life and nonlife) were selected, and the brain structure of individuals was obtained by magnetic resonance imaging, while the whole brain activity in the picture naming task was detected by magnetoencephalogram (MEG). Results: In the picture naming tasks, early brain activation started in the bilateral occipital lobes, gradually spread to the temporal and parietal lobes, and finally generated the speech production in the frontal lobes. In the visual related time windows, the activation of nonlife categories picture naming in the right cingulate gyrus was significantly greater than the life (P=0.0475), while the activation of life categories in the bilateral occipital lobes, left parietal lobe and left frontal lobe was significantly greater than the nonlife (all P<0.05). In the semantic related time windows, the activation of life categories in the bilateral frontal lobes was significantly greater than nonlife categories (P<0.05). In the phonological related time windows, the activation of life categories in the bilateral occipital lobes, left parietal lobe and left frontal lobe was significantly greater than nonlife categories (all P<0.05). Conclusion: Compared with the picture naming of nonlife categories, naming of life categories had no significant difference in temporal lobe activity but showed a dominant activation in occipital, parietal and frontal lobes, which suggested that picture naming of life categories can stimulate the related functional regions in the related time windows better. |
