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07:14
A Method to Study Adaptation to Left-Right Reversed Audition
Published on: October 29, 2018
Environmental reverberation affects processing of sound intensity in right temporal cortex
Christian F Altmann1, Kentaro Ono, Akiko Callan
1Graduate School of Medicine, Human Brain Research Center, Kyoto University, Kyoto, Japan; Career-Path Promotion Unit for Young Life Scientists, Kyoto University, Kyoto, Japan.
The European Journal of Neuroscience
|July 23, 2013
Summary
Sound reverberation aids loudness constancy, enabling perception of stable loudness despite changing distances. This study found strong reverberation supports loudness constancy, with brain activity in temporal lobes reflecting this auditory processing.
Area of Science:
- Auditory Neuroscience
- Psychoacoustics
- Human Auditory Perception
Background:
- Sound reverberation is typically viewed as noise in auditory studies.
- However, reverberation may play a role in loudness constancy, maintaining perceived loudness despite variations in sound source distance.
Purpose of the Study:
- To investigate the influence of room reverberation on psychophysical loudness constancy.
- To identify neural correlates of loudness constancy using magnetoencephalography (MEG).
Main Methods:
- Manipulation of room reverberation characteristics.
- Psychophysical testing of loudness perception and sound distance judgment.
- MEG recordings in human subjects during auditory tasks.
Main Results:
- Loudness constancy was observed in strong reverberation but not weak reverberation conditions.
- Sound distance judgments were consistently dependent on actual distance across reverberation conditions.
- MEG data revealed neural activity reflecting loudness constancy (constant evoked magnetic field scaling with distance) in strong reverberation, contrasting with inverse scaling in weak reverberation, from ~210-270 ms post-stimulus onset.
- Source reconstruction localized neural generators to the right middle and inferior anterior temporal lobes.
Conclusions:
- Reverberation cues are directly utilized for constructing loudness constancy, dissociating it from distance perception.
- Auditory association areas in the right temporal cortex are implicated in processing loudness constancy.
- This research highlights a novel role for reverberation in auditory perception.
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