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The Effect of Cochlear Damage on the Sensitivity to Harmonicity.
Damien Bonnard1, René Dauman, Catherine Semal
11Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, CNRS and Université de Bordeaux (UMR 5287), Bordeaux, France; 2Centre Hospitalier Universitaire Pellegrin, Université de Bordeaux, Bordeaux, France; and 3Institut Polytechnique de Bordeaux, Bordeaux, France.
Ear and Hearing
|December 20, 2016
Summary
Sensitivity to harmonicity is generally robust but can be reduced by mild or moderate cochlear hearing loss. Listeners with hearing loss may also detect inharmonicity differently than normal-hearing individuals.
Area of Science:
- Auditory perception
- Psychoacoustics
- Hearing science
Background:
- Harmonic fusion allows perception of simultaneous pure tones as a single sound.
- This phenomenon is crucial for auditory scene analysis, enabling segregation of complex sounds.
- Cochlear hearing loss may impact the ability to perceive harmonic relationships.
Purpose of the Study:
- To investigate the effects of mild to moderate cochlear hearing loss on sensitivity to harmonicity.
- To examine how hearing loss influences the detection of inharmonicity.
Main Methods:
- 12 normal-hearing (NH) and 8 hearing-impaired (HI) listeners participated.
- Thresholds for detecting changes in frequency ratios (harmonic vs. inharmonic) were measured.
- Stimuli were presented within broadband noise at low sensation levels, with randomized frequency registers.
Main Results:
- Both NH and HI listeners showed sensitivity to harmonicity, though it was weaker in some HI listeners.
- NH listeners detected inharmonicity asymmetrically (better detection of frequency ratio compression).
- HI listeners showed symmetric inharmonicity detection, regardless of deviation direction.
Conclusions:
- Sensitivity to harmonicity is largely preserved but can be diminished by cochlear damage.
- Cochlear hearing loss may alter the mechanisms of inharmonicity detection, leading to symmetric perception.
- Listeners with cochlear damage might not process inharmonic sounds in the same way as NH listeners.
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