The spatiotemporal characteristics of brain activation during picture naming tasks / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To explore the temporal and spatial changes of the whole brain during the picture naming tasks and the influence of different semantic similarity in the blocked-cyclic paradigm.Methods:Ten healthy right-handed adults were selected.The blocked-cyclic paradigm is divided into two naming tasks consist of related and unrelated pictures.The brain activation of the whole brain in different time windows was recorded by magnetoencephalography(MEG) during the picture naming tasks.Results:In the visual-related time windows, the dominant regions appeared in the related picture naming task, located in left frontal pole (1.421±0.468), right frontal pole (1.431±0.435), left orbitofrontal gyrus(1.601±0.620), right orbitofrontal gyrus (1.567±0.556), left superior frontal gyrus (1.899±0.062), right superior parietal gyrus (5.218±0.678) and left lingual gyrus (5.016±0.088) compared with the unrelated picture naming task (1.038±0.217, 1.131±0.235, 1.312±0.316, 1.253±0.340, 1.710±0.151, 4.538±0.478, 4.275±0.251), the differences were statistically significant ( P<0.05). In the semantic-related time windows, the dominant regions appeared in the unrelated picture naming task, located in left paracentral lobule (3.176±0.392), right cuneus (4.190±0.330), left posterior cingulate (2.430±0.196) and right posterior cingulate (2.405±0.236) compared with the related picture naming task (2.594±0.254, 3.626±0.560, 2.038±0.115, 1.990±0.094), and the differences were statistically significant ( P<0.05). In the phonological-related time windows, the dominant regions appeared in the unrelated picture naming task, located in left superior temporal sulcus (3.709±0.274), left superior temporal gyrus (3.901±0.380), left middle temporal gyrus (3.340±0.380), left transverse temporal gyrus (4.449±0.265), left supramarginal gyrus (3.205±0.308), left insula (3.140±0.204), left anterior cingulate (2.217±0.194) and right anterior cingulate (2.341±0.167) compared with the related picture naming task (2.662±0.300, 2.503±0.342, 2.614±0.324, 2.633±0.281, 2.663±0.278, 2.248±0.284, 1.818±0.315, 2.005±0.437), and the differences were statistically significant ( P<0.05). Conclusion:In different time windows, semantic similarities can lead to differences in brain activation.The related picture naming task can cause the dominant activation of bilateral prefrontal lobe in the visual processing stage, which may be related to sustained attention and category judgment while the unrelated picture naming task can cause dominant activation of the left temporal gyrus, left insula and bilateral limbic system during speech processing, which corresponds to semantic coding and phonology introspection.