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Updated: Jun 12, 2026
09:32
Evaluation of Auditory Brainstem Response in Chicken Hatchlings
Published on: April 1, 2022
Peripheral auditory processing changes seasonally in Gambel's white-crowned sparrow
Melissa L Caras1, Eliot Brenowitz, Edwin W Rubel
1Neurobiology and Behavior Graduate Program, University of Washington, Mail Stop 351525, Seattle, WA 98195, USA.
Summary
Seasonal changes and hormones affect songbird hearing. Birds in breeding conditions showed reduced auditory function, indicating hormonal impacts on auditory processing, not just vocal production.
Area of Science:
- Neuroscience
- Animal Behavior
- Auditory Physiology
Background:
- Song learning in oscine birds is crucial for breeding and exhibits seasonal variation.
- Hormones, primarily androgens and estrogens, mediate seasonal changes in song production.
- Limited research exists on seasonal and hormonal effects on peripheral auditory processing in songbirds.
Purpose of the Study:
- To investigate the impact of seasonal changes and hormones on peripheral auditory processing in Gambel's white-crowned sparrows.
- To determine if auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAEs) are affected by simulated breeding and non-breeding conditions.
Main Methods:
- Manipulated photoperiod and hormone levels in laboratory settings to mimic breeding and non-breeding seasons.
- Assessed peripheral auditory function using auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAEs).
- Measured ABR thresholds, peak latencies, and DPOAEs in male and female sparrows under different simulated conditions.
Main Results:
- Birds under breeding-like conditions exhibited elevated ABR thresholds and prolonged peak latencies compared to non-breeding conditions.
- No significant changes were observed in DPOAEs between the two conditions.
- The observed ABR changes are not attributable to alterations in hair cell function.
Conclusions:
- Seasonal factors and hormones influence auditory processing in wild songbirds, similar to their effects on vocal production.
- Peripheral auditory system function is modulated by seasonal hormonal changes.
- This study highlights the broader impact of seasonal plasticity on sensory systems in songbirds.
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