Controlling signal-to-noise ratio effects in the measurement of speech intelligibility in fluctuating maskers

Authors

  • Joshua G. W. Bernstein Audiology and Speech Center, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA

Abstract

The measurement of speech intelligibility in noise is often complicated by floor and ceiling effects. Because of this, adaptive methods are often used to determine the signal-to-noise ratio (SNR) required for a fixed performance level. Unfortunately, such methods relinquish control of the test SNR, confounding data interpretation when the effect of interest is SNRdependent. For example, the intelligibility improvement afforded by glimpsing the target speech during brief dips in the level of a fluctuating masker is highly SNR-dependent. Thus, comparisons of performance in stationary and fluctuating maskers are susceptible to SNR confounds. Various methods of controlling SNR differences in the measurement of speech intelligibility are discussed, including the development and validation of a standardized intelligibility testing procedure that uses a variable response set size to control SNR differences. The application of these techniques to studies of hearing loss or simulated hearing loss demonstrate that impaired listeners may retain the ability to listen in the dips of a fluctuating masker to a much greater extent than previously thought.

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Published

2011-12-15

How to Cite

Bernstein, J. G. W. (2011). Controlling signal-to-noise ratio effects in the measurement of speech intelligibility in fluctuating maskers. Proceedings of the International Symposium on Auditory and Audiological Research, 3, 33–44. Retrieved from http://proceedings.isaar.eu/index.php/isaarproc/article/view/2011-04

Issue

Section

2011/1. Indicators of hearing impairment and measures of speech perception