Asymmetries for the categorization of kanji nouns, adjectives, and verbs presented to the left and right visual fields

Kanji is one form of written Japanese in which the symbolic/analytic characteristics of language are dissociated from systematic phonetic characteristics; as such, it makes possible a more careful test of which aspect of language is responsible for the frequently observed superior left-hemisphere performance. In this study, subjects were asked to categorize tachistoscopically presented kanji as nouns, adjectives, or verbs. The previously reported (Hatta 1977, Neuropsychologia, 15, 685–688) left-visual-field advantage for kanji was found only in the case of nouns. Adjectives and verbs were processed more rapidly and correctly in the right visual field.