Abstract: The laterality of hemispheric function was tested by using Chinesecharacters which were two sets of word pairs that had same phoneme orlooked alike. The reaction time of the right field-left hemisphere wassuperior for the word pairs of the same phoneme but the left field-righthemisphere was superior for the looking alike. word pairs The ERPamplitude, especially P300, was significant smaller for left hemispherecomparring to right hemisphere under same phoneme condition. TheERP had no clear difference between left and right hemisphere for thewords pairs that looked alike. The latency of ERP also had no differen-ce between the left and right hemispheres under the two kinds of materialconditions. The results indicate that the left hemisphere relates to phone-mic coding of Chinese words and ERP (P300) seems to be its effectiveindex.

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