Detecting changes in dynamic and complex acoustic environments
Abstract
Natural sounds such as wind or rain, are characterized by the statistical occurrence of their constituents. Despite their complexity, listeners readily detect changes in these contexts. We here address the neural basis of statistical decision-making using a combination of psychophysics, EEG and modelling. In a texture-based, change-detection paradigm, human performance and reaction times improved with longer pre-change exposure, consistent with improved estimation of baseline statistics. Change-locked and decision-related EEG responses were found in a centro-parietal scalp location, whose slope depended on change size, consistent with sensory evidence accumulation. The potential's amplitude scaled with the duration of pre-change exposure, suggesting a time-dependent decision threshold. Auditory cortex-related potentials showed no response to the change. A dual timescale, statistical estimation model accounted for subjects' performance. Furthermore, a decision-augmented auditory cortex model accounted for performance and reaction times, suggesting that the primary cortical representation requires little post-processing to enable change-detection in complex acoustic environments.
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Author details
Funding
Agence Nationale de la Recherche (ANR-10-LABX-0087 IEC)
- Yves Boubenec
- Jennifer Lawlor
- Shihab Shamma
- Bernhard Englitz
Agence Nationale de la Recherche (ANR-10-IDEX-0001-02 PSL*)
- Yves Boubenec
- Jennifer Lawlor
- Shihab Shamma
- Bernhard Englitz
Advanced European Research Council (ERC 295603)
- Yves Boubenec
- Jennifer Lawlor
- Shihab Shamma
- Bernhard Englitz
European Commission's Marie Curie grant (660328)
- Bernhard Englitz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All experiments were performed in accordance with the guidelines of the Helsinki Declaration. The Ethics Committees for Health Sciences at Université Paris Descartes approved the experimental procedures.
Copyright
© 2017, Boubenec et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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