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Published on: September 7, 2022
Sound stimulus qualities and severe auditory neglect.
J Michael Williams1, A Rand Coleman
1Drexel University, Philadelphia, PA 19102, USA. jw37@drexel.edu
Neurocase
|July 9, 2008
Summary
Severe auditory neglect after a stroke was not improved by cues or increased sound volume. This suggests brain processing of sound volume differs from simple neural firing rates.
Area of Science:
- Neuroscience
- Audiology
- Neurology
Background:
- Auditory neglect is a deficit in processing auditory information from the contralateral ear.
- Cerebral vascular accidents (CVAs) can cause various neurological deficits, including neglect syndromes.
Observation:
- A patient with a right hemisphere CVA developed severe left auditory neglect.
- Auditory neglect severity was assessed using pure tones, speech, and environmental stimuli via binaural and dichotic presentation.
- A dichotic word test evaluated implicit and explicit cuing effects on auditory perception.
Findings:
- Implicit semantic cues did not reduce auditory neglect.
- Increasing sound volume in the neglected ear did not improve perception of left-sided stimuli.
- Explicit commands to attend to the left ear were ineffective in enhancing perception.
Implications:
- Some auditory neglect symptoms are independent of stimulus attributes like volume.
- Findings challenge the notion of sound volume being a simple analogue representation, suggesting it's processed as encoded information.
- This case provides insights into the neural processing of auditory information and neglect syndromes.
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