Discrimination of Complex Sounds by Hearing-Impaired Listeners
Threshold measures such as the pure-tone audiogram might tell us how well a person
hears but they cannot
tell us how well a person listens. How might reduced sensitivity for particular
frequencies affect the
distribution of attention across frequency? In this project we apply a recently developed
analytical
techniques to assess how normal-hearing and sensorineural hearing-impaired listener's
attend to the
information contained in the individual frequencies of suprathreshold sounds. The result
is an information
weighting function of frequency, what we refer to as a pure-tone infogram. Our early
studies indicate that
listeners with high-frequency sensorineural hearing loss make greater use of high-
frequency information
than low even though this strategy is nonoptimal. It is as if the hearing-impaired listeners
somehow attempt
to compensate for their loss by attending more to information in a region of reduced
sensitivity. The results
cannot be explained by a general tendency to listen at high frequencies since the normal-
hearing listeners
do not show such a trend. We are currently experimenting with ways of improving the
performance of
hearing-impaired listeners in these tasks by modifying their weighting function or by
'repackaging' the
information so as to match their weighting function.
Selected Publications
Lutfi, R. A. (1987). Masking additivity in the hearing-impaired. Hearing Research, 25, 3-10. *
Doherty, K. A., and Lutfi, R. A. (1992). Pure-tone infograms measured in listeners with
sensorineural hearing loss. Abstracts of the 15th Midwinter Research Meeting, ARO, Edited by D. J. Lim. *
Doherty, K.A., and Lutfi, R. A. (1993). Spectral weighting functions in hearing-impaired listeners using COSS analysis. American Speech-Language-Hearing Association, Fall Conference, Los Angeles, CA. *
Lutfi, R. A. (1994). Correlation coefficients and correlation ratios as estimates of
observer weights in multiple-observation tasks. Journal of the Acoustical Society of
America 97, 1333-1334. *
Doherty, K. A., and Lutfi, R. A. (1994). Spectral weights for level discrimination in
listeners with sensorineural hearing loss. Journal of the Acoustical Society of America 99, 1053-1058. *
Lutfi, R.A., and Doherty, K.A. (1996). Modeling level discrimination of broadband signals by listeners
with sensorineural hearing loss. Chapter in
Modeling Sensorineural Hearing Loss. Editor: Jesteadt, W., Erlbaum Press: New York, pp. 235-245