Auditory perpetual dysfunction in patients with CCI, with implications for therapy.

Injury to the head, as from impact, can result in damaged function of the auditory receptive (peripheral) or perceptual (central) system, or both. The altered function may be clearly apparent, as in a loss of hearing, or may be exposed only through specially devised tests. At the Loewenstein Rehabilitation Hospital tests were designed or adapted to evaluate processing in the auditory periphery, the brain stem and the cortex. With speech as the the stimulus the tasks explore binaural interaction, cerebral hemisphere dominance and suppression, and cognitive efficiency in understanding degraded speech messages. Other stimuli, such as pure tones and musical patterns are employed to reveal dysfunction on various levels of the system. This report concentrates on tests which require the cerebral hemispheres to listen competitively. Results are given for earphone listening and for two new types of selective listening tasks in the sound field (loudspeaker) mode.