Objective: To determine the relation of age-related auditory processing dysfunction and executive functioning.
Background: Central auditory dysfunction is common in Alzheimer dementia, but the mechanism is not established.
Method: A total of 313 volunteers from the Adult Changes in Thought surveillance cohort with adequate peripheral hearing were included in the study. Outcome measures such as (1) peripheral audition; (2) auditory-evoked potentials; (3) central auditory tests (Synthetic Sentence Identification with Ipsilateral Competing Message, Dichotic Sentence Identification, Dichotic Digits); (4) Executive Functioning: Trail Making; Clock Drawing, Stroop Color and Word, and subtests from the Cognitive Abilities Screening Instrument were used to measuring the mental concentration. A composite executive functioning score was created using item response theory.
Results: The composite executive functioning score was significantly associated with each central auditory measure, explaining 8% to 21% of the variance. Trails B test was most strongly associated with the auditory outcomes, explaining 8% to 14% of the variance. The relation between executive functioning and central auditory function was still significant when participants diagnosed with memory impairment or dementia were excluded.
Conclusions: In elderly persons, reduced executive functioning is associated with central auditory processing, but not with primary auditory function. This suggests that central presbycusis and executive dysfunction may result from similar neurodegenerative processes.
*Department of Otolaryngology—Head Neck Surgery
†Department of General Internal Medicine
‡Department of Psychosocial and Community Health, University of Washington
§Group Health Center for Health Studies, Seattle, WA
Supported by DC01525 from the National Institute for Deafness and Other Communication Disorders and ADPR AG06781 and P50AG05136 from the National Institute of Aging.
Reprints: George A. Gates, MD, Virginia Merrill Bloedel Hearing Research Center, University of Washington, Box 357923, CHDD Bldg. RM CD176, Seattle, WA 98195-7923 (e-mail: firstname.lastname@example.org).
Received July 9, 2009
Accepted January 31, 2010