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Published on: December 22, 2015
Spectral shape discrimination of narrow-band sounds
The Journal of the Acoustical Society of America
|November 1, 1992
Summary
Detecting signals in narrow-band sounds depends on how the sound
Area of Science:
- Auditory perception
- Psychoacoustics
- Signal detection theory
Background:
- Narrow-band sounds are fundamental in auditory research.
- Understanding signal detectability is crucial for auditory models.
Purpose of the Study:
- To investigate the detectability of various signals added to narrow-band sounds.
- To explore the acoustic cues listeners use for signal detection.
- To propose and test a model for signal detection in narrow-band auditory stimuli.
Main Methods:
- Experiments involved presenting narrow-band sounds (20 Hz bandwidth) with added sinusoidal signals.
- Signals created symmetric or asymmetric spectral changes.
- Sound levels were randomly varied to decouple signal presence from absolute level.
- Computer simulations were used to test a proposed detection model.
Main Results:
- Symmetric signals were detected based on changes in the envelope power spectrum, perceived as altered sound roughness.
- Asymmetric signals were primarily detected through pitch changes.
- Model predictions aligned with experimental findings.
Conclusions:
- Listener detection strategies differ for symmetric and asymmetric spectral changes in narrow-band sounds.
- Envelope power spectrum changes and pitch shifts are key auditory cues.
- The proposed model effectively predicts detection performance for symmetric signals.
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