Related Experiment Videos
The auditory brainstem response of aged guinea pigs
N J Ingham1, S K Thornton, S D Comis
1Department of Physiology, Worsley Medical and Dental Building, University of Leeds, UK. n.j.ingham@leeds.ac.uk
Acta Oto-Laryngologica
|December 5, 1998
Summary
Aging in guinea pigs causes significant hearing threshold elevations, primarily due to conductive hearing loss, not brainstem dysfunction. Some older animals experienced severe sensorineural hearing loss.
Area of Science:
- Auditory Neuroscience
- Gerontology
- Comparative Physiology
Background:
- Biological aging can affect sensory systems, including hearing.
- The auditory brainstem response (ABR) is a valuable tool for assessing auditory pathway function.
- Understanding age-related hearing changes in animal models aids human research.
Purpose of the Study:
- To investigate age-related changes in the auditory brainstem using ABR in guinea pigs.
- To differentiate between conductive and sensorineural hearing loss in aging animals.
Main Methods:
- Auditory brainstem responses (ABR) were recorded in guinea pigs across a wide age range (58 days to over 4 years).
- Stimulation intensities varied from -10 dB HL to 85 dB HL.
- Auditory thresholds, wave latencies, and inter-peak intervals were analyzed.
Main Results:
- Auditory thresholds significantly elevated in older guinea pigs (average 32 dB).
- Latency/intensity functions shifted rightward in older animals, indicating conductive hearing loss.
- No significant age-related changes in wave latencies or inter-peak intervals were found.
- 24% of older animals showed no ABR, suggesting severe sensorineural hearing loss.
Conclusions:
- Age-related hearing threshold elevations in guinea pigs are primarily due to conductive hearing loss, likely in the middle ear.
- The auditory brainstem itself shows no significant age-related dysfunction.
- Severe sensorineural hearing loss occurs in a subset of aging guinea pigs.