Sideways look at dichotic listening

The present experiment investigates the possibility that performance on the dichotic listening task is systematically influenced by variables unrelated to the linguistic or auditory character of the stimuli employed. Subjects sat in a lighted room with head position fixed and listened to a standard dichotic CV tape. Binocular Risley prisms were used to displace the subjects' visual environment either 13° to the left, 13° to the right, or not at all. A right ear advantage was obtained in the no‐displacement condition (percentage of correct responses contributed by the right ear—POC—was 55.5%). This advantage was decreased in the left‐displacement condition (POC = 51.8%) and was increased in the right‐displacement condition (POC = 57.1%). This result indicates that subjects' performance on the dichotic listening task may reflect a number of psychological and physiological factors, in addition to a possible cortical hemispheric specialization for language. Among the factors considered are attention (of an involuntary sort) and spatial orientation mechanisms normally involved in sound localization and binaural fusion.