Effects of Aging and Gender on Interhemispheric Function The ability of the two hemispheres of the brain to communicate with one another via the corpus callosum is important for a wide variety of sensory, motor, and cognitive functions, many of them communication related. Anatomical evidence suggests that aging results in structural changes in the corpus callosum and that ... Research Article
Research Article  |   April 01, 2001
Effects of Aging and Gender on Interhemispheric Function
 
Author Affiliations & Notes
  • Teri James Bellis
    Department of Communication Disorders University of South Dakota Vermillion, SD
  • Laura Ann Wilber
    Department of Communication Sciences and Disorders Northwestern University Evanston, IL
  • Corresponding author: e-mail: tbellis@usd.edu
Article Information
Special Populations / Older Adults & Aging / Hearing / Research Articles
Research Article   |   April 01, 2001
Effects of Aging and Gender on Interhemispheric Function
Journal of Speech, Language, and Hearing Research, April 2001, Vol. 44, 246-263. doi:10.1044/1092-4388(2001/021)
History: Received May 4, 2000 , Accepted November 2, 2000
 
Journal of Speech, Language, and Hearing Research, April 2001, Vol. 44, 246-263. doi:10.1044/1092-4388(2001/021)
History: Received May 4, 2000; Accepted November 2, 2000
Web of Science® Times Cited: 45

The ability of the two hemispheres of the brain to communicate with one another via the corpus callosum is important for a wide variety of sensory, motor, and cognitive functions, many of them communication related. Anatomical evidence suggests that aging results in structural changes in the corpus callosum and that the course over time of age-related changes in corpus callosum structure may depend on the gender of the individual. Further, it has been hypothesized that age- and gender-related changes in corpus callosum structure may result in concomitant decreased performance on tasks that are reliant on interhemispheric integrity. The purpose of this study was to investigate the effects of age and gender on auditory behavioral and visuomotor temporal indices of interhemispheric function across the life span of the normal adult. Results from 120 consistently right-handed adults from age 20 to 75 years revealed that interhemispheric integrity, as measured by dichotic listening, auditory temporal patterning, and visuomotor interhemispheric transfer time tasks, decreases relatively early in the adult life span (i.e., between the ages of 40 and 55 years) and shows no further decrease thereafter. In addition, the course over time of interhemispheric decline is different for men compared to women for some tasks. These findings suggest that decreased interhemispheric function may be a possible factor contributing to auditory and communication difficulties experienced by aging adults. In addition, results of this study hold implications for the clinical assessment of interhemispheric function in aging adults and for future research into the functional ramifications of decreased multimodality interhemispheric transfer.

Acknowledgments
This research was supported in part by a Dissertation Year Grant from Northwestern University, Evanston, IL. The authors gratefully acknowledge the assistance provided by Dean Garstecki, Nina Kraus, Frank Musiek, and Steve Zecker.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access