Temporal aspects of dichotic listening in brain-damaged subjects

Thirteen cortically injured subjects were tested in a dichotic temporal order judgment task using speech and nonspeech stimuli. Subjects were required only to judge which ear was stimulated first on each trial. All were young men and neurologically normal before receiving missile wounds. Subjects with injuries outside the temporal and frontal lobes performed the dichotic tasks at levels comparable to that of neurologically normal subjects. In contrast, subjects with temporal lobe lesions performed at near chance levels on all of the conditions. Individuals with frontal lobe damage showed moderate impairment on the dichotic tasks.