Dichotic listening, event-related potentials, and interhemispheric transfer in the elderly.
OBJECTIVE
To determine the basis for the large, age-related asymmetries in dichotic listening performance scores reported by Jerger et al. (1994).


METHODS
Behavioral and electrophysiologic responses to dichotic listening tasks in both verbal and nonverbal paradigms were obtain in four groups of subjects: young adults with normal hearing, elderly persons with presbyacusis, elderly persons with presbyacusis and marked dichotic deficits, and patients with lesions of the corpus callosum.


RESULTS
In comparison with the young group the two elderly groups showed an increasing left-ear deficit on the verbal task, and an increasing right-ear deficit on the nonverbal paradigm. The pattern of results obtained in the elderly persons with marked dichotic deficits was similar to the pattern of results in the group with callosal lesions.


CONCLUSIONS
With age, there may be a significant loss of efficiency of interhemispheric transfer of auditory information through the corpus callosum. Such age-related deficit might have important implications for the effective use of binaural information by elderly person.
Jerger
J
J
Department of Otorhinolaryngology and Communicative Sciences, Baylor College of Medicine, Houston, Texas, USA.
Alford
B
B
Lew
H
H
Rivera
V
V
Chmiel
R
R
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001301:Audiometry, Pure-Tone; D001931:Brain Mapping; D003337:Corpus Callosum / Q000503:physiopathology*; D004007:Dichotic Listening Tests; D005072:Evoked Potentials, Auditory; D005260:Female; D007839:Functional Laterality; D006309:Hearing / Q000502:physiology; D006311:Hearing Disorders / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011930:Reaction Time; D013067:Speech Perception