To investigate the nature of the task-stimulus interaction in tachistoscopic recognition of kana and kanji, right-handed normal subjects performed two phonological tasks and two visual tasks. In the phonological tasks, the subjects compared the members of a pair of kana or kanji appearing in the right or left visual field on the basis of phonological identity; while in the visual tasks, they compared the members of a pair of kana or kanji on the basis of visual identity. The results showed a significant Visual Field × Task interaction as well as a significant Task × Stimulus interaction, indicating that both the type of stimuli and the nature of task demands contribute importantly to the determination of visual field asymmetry and hence the relative participation of each hemisphere.