Dichotic listening and the cerebral organization of the phonetic and semantic components of language.

Two words were presented dichoticly and the subject was required to point to visually presented words that either rhymed with or were semantically related to those words. Task demands were varied in terms of the number and type of stimuli which the auditory and visual words actually matched. Performance was superior when either type of stimulus was presented to the Left Hemisphere via the Right Ear, resulting in the standard Right Ear Advantage (REA) for verbal material. The strength of the REA, however, depended both on the type of stimuli and the specific demands of the task. It was concluded that, since language has many components, dichotic listening can be used to investigate the relative contributions of the two cerebral hemispheres to those various components.