Dominance of recognition of words presented on right or left eye —Comparison of Kanji and Hiragana—

Abstract

This chapter presents the nineteen-channel event-related potentials (ERPs) recorded during recognition of two types of Japanese characters—Kanji (Chinese characters) and Hiragana. By field-sequential stereoscopic 3D display with liquid crystal shutter, a word and a nonword were simultaneously and independently presented to the left (right) eye and right (left) one, respectively. Each word consisted of two Kanji or three Hiragana characters. Three subjects were instructed to press a button when understanding the meaning of the visual stimuli after 3000 ms poststimulus. Equivalent current dipole source localization (ECDL) with three unconstrained ECD was applied to the ERPs. For both Kanji and Hiragana, the ECDs were localized to the occipital, lingual, and inferior temporal gyri at 200–350 ms, and those at Wernicke's area at 350–600 ms. The latter ECD for one left-handed subject was located at Wernicke's homologue. The Kanji recognition revealed the activation of the fusiform and supramarginal gyri, which might reflect binocular rivalry and spatial working memory. During the Hiragana recognition task, one of the ECDs was located at the angular gyrus, which was related to phonological processing. For one left-handed subject, the inferior parietal ECDs were localized contralaterally to those of right-handed subjects.