Character Voice Processing Lateralization Of Brain Function And Its Integration

Objective: The study was to investigate the cerebral functional lateralization and integration of different handedness in processing different phonetic components of Chinese characters and the phonetics associated with semantics.Methods: Twenty-six right-handers and twenty-four left-handers were examined using two pairs of one group dichotic listening (DL) test of the phonetics of Chinese characters by presenting the information matched under different within-ear and inter-ear conditions to investigate the relationships of Chinese handedness and the cerebral functional lateralization and integration. Utilizing perceptive match tasks, Experiment 1 was to investigate the cerebral functional lateralization and integration when subjects were processing rhyme, tone and consonant of Chinese characters under different attention(pre-attention and post-attention)conditions. Utilizing semantic category tasks, experiment 2 was to investigate the cerebral functional lateralization and integration in processing the phonetics of Chinese characters associated with semantics.Results:The results of expreriment 1 indicated that,under pre-attention condition, there was within-ear(within-hemisphere) dominance for the perception of the whole syllable, consonant and ryhme of Chinese characters, but inter-ear(interhemisphere) dominance for the perception of the tone; Under post-attention condition, there was within-hemisphere dominance for the perception of the whole syllable and consonant, but no significant differences between within-hemisphere and interhemisphere for the perception of the ryhme and tone. For the cerebral functional lateralization, subjects showed significant left hemispheric dominance, especially for the perception of the rhyme and tone. For cerebral functional integration, the results indicated left hemisphere advantage for the perception of the whole syllable, ryhme and tone. In the consonant of Chinese characters tasks, the tendency was the same. Right-handers responded more quickly than left-handers,especially in the perception the tone. For the cerebral functional lateralization and integration, there was no significant differences between right-handers and left-handers.The results of expreriment 2 showed right hemispheric lateralization dominance and left hemispheric integration dominance in processing the phonetics of Chinese characters associated with semantics.The response of right-handers were more quickly than that of left-handers.The right hemispheric dominance was more significant when the response hand was handedness.Conclusions: (1) Under pre-attention condition,there was within-hemispheric dominance for the perception of the whole syllable,consonant and ryhme of Chinese characters, but interhemispheric dominance for the perception of the tone; Under post-attention condition, there was within-hemispheric dominance for the perception of the whole syllable and consonant, but no significant difference between within-hemisphere and interhemisphere for the perception of the ryhme and tone. In processing the phonetics of Chinese characters associated with semantics, subjects showed within-hemispheric dominance.These may be related with task properties and task complexity levels which was aroused by different attention conditions.(2) For the cerebral functional lateralization, they showed left hemispheric dominance tendency when subjects were in processing different components of Chinese character syllable, but right hemispheric dominance tendency in processing the phonetics of Chinese characters associated with semantics. For cerebral functional integration, the results indicated left hemispheric advantages tedency for the perception of different components of Chinese character syllable and there was no significant differences between hemispheres in processing the phonetics of Chinese characters associated with semantics.(3) For the perception of different components of Chinese character syllables, there were no differences in the cerebral functional lateralization and integration between right-handers and left-handers. The reason may be that most left-handers were non-familial left-handers and the task was perceptive distinguishment.(4)In processing the phonetics of Chinese characters associated with semantics, the right hemispheric dominance was more significant when the response hand was handedness. The reason may be that handedness was so proficient that needed less brain resources.