The effect of basilar-membrane nonlinearity on the shapes of masking period patterns in normal and impaired hearing.

Abstract

Masking period patterns (MPPs) were measured in listeners with normal and impaired hearing using amplitude-modulated tonal maskers and short tonal probes. The frequency of the masker was either the same as the frequency of the probe (on-frequency masking) or was one octave below the frequency of the probe (off-frequency masking). In experiment 1, MPPs were measured for listeners with normal hearing using different masker levels. Carrier frequencies of 3 and 6 kHz were used for the masker. The probe had a frequency of 6 kHz. For all masker levels, the off-frequency MPPs exhibited deeper and longer valleys compared with the on-frequency MPPs. Hearing-impaired listeners were tested in experiment 2. For some hearing-impaired subjects, masker frequencies of 1.5 kHz and 3 kHz were paired with a probe frequency of 3 kHz. MPPs measured for listeners with hearing loss had similar shapes for on- and off-frequency maskers. It was hypothesized that the shapes of MPPs reflect nonlinear processing at the level of the basilar membrane in normal hearing and more linear processing in impaired hearing. A model assuming different cochlear gains for normal versus impaired hearing and similar parameters of the temporal integrator for both groups of listeners successfully predicted the MPPs.

• Authors: M Wojtczak, A C Schroder, Y Y Kong, D A Nelson
• Journal: The Journal of the Acoustical Society of America (J Acoust Soc Am) Vol. 109 Issue 4 Pg. 1571-86 (Apr 2001) ISSN: 0001-4966 [Print] United States
• PMID: 11325128 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Topics

• Auditory Perception (physiology)
• Auditory Threshold (physiology)
• Basilar Membrane (physiology)
• Hearing (physiology)
• Hearing Loss, High-Frequency (diagnosis)
• Hearing Loss, Sensorineural (diagnosis)
• Humans
• Models, Biological
• Perceptual Masking
• Time Factors