Hemifield Differences in Binocular Fusion

Abstract

Laterality differences in binocular fusion of digits was examined using groups of Ss with either left to right or right to left reading habits. In hemifield presentation, opposing laterality differences were found between the groups when presentation was 8° 30' off center. English readers showed right visual-field preference, while Hebrew readers showed the opposite, but no laterality differences were observed at 3° presentation. In simultaneous presentation to both fields fusion was superior in the right visual field in both groups. The results obtained in hemifield presentation were in accordance with those obtained in conventional tachistoscopic perception of verbal material and can be explained by directional scanning tendencies. The results obtained in simultaneous presentation to both fields can be interpreted as demonstrating left cerebral dominance for perception of verbal stimuli. It is concluded that cerebral dominance in visual perception of verbal material can be demonstrated in situations where different inputs in crossed and uncrossed sensory projections are delivered to both hemispheres simultaneously.