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Updated: May 10, 2026
07:52
An Automated System for Sound Localization Testing in Hearing-Impaired Listeners
Published on: March 13, 2026
Sound localization in noise and sensitivity to spectral shape
Guillaume Andéol1, Ewan A Macpherson, Andrew T Sabin
1Institut de Recherche Biomédicale des Armées, Département Action et Cognition en Situation Opérationnelle, BP 73, 91223 Brétigny sur Orge Cedex, France.
Hearing Research
|June 18, 2013
Summary
Individual differences in sound localization performance are linked to perceptual abilities, not acoustic factors. Listeners with better sensitivity to spectral shape, particularly at low modulation frequencies, exhibit superior sound localization skills.
Area of Science:
- Auditory Neuroscience
- Psychoacoustics
- Human Perception
Background:
- Individual variations in sound localization performance are evident even in individuals with normal hearing.
- These differences may stem from acoustic variations in head-related transfer functions (HRTFs) or perceptual factors.
Purpose of the Study:
- To investigate the influence of spectral strength (acoustic factor) and spectral shape sensitivity (perceptual factor) on individual differences in sound localization.
- To determine whether acoustic or perceptual factors are more critical in explaining these performance variations.
Main Methods:
- Calculated spectral strength from HRTF magnitude spectra.
- Assessed listener sensitivity to spectral shape using spectral-modulation thresholds across different carrier frequencies and modulation frequencies.
- Correlated these acoustic and perceptual measures with sound localization performance in 19 young normal-hearing listeners.
Main Results:
- Lower spectral-modulation thresholds with high-frequency carriers below 1 cycle/octave correlated with better sound localization performance.
- No significant correlation was found between sound localization performance and the spectral strength of HRTFs.
- Perceptual sensitivity to spectral shape emerged as a key factor in individual localization differences.
Conclusions:
- Individual differences in sound localization performance are primarily driven by perceptual factors, specifically sensitivity to spectral shape.
- Acoustic properties of the head-related transfer functions (HRTFs) do not appear to be the main source of these individual variations.
- Enhanced perceptual abilities in processing spectral information contribute to more accurate sound localization in noise.
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