ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2pPP37. Efficiency of selective listening by normal-hearing and hearing-impaired listeners.

Karen A. Doherty

Commun. Sci. and Disorders, Syracuse Univ., 805 S. Crouse Ave., NY 13244

Robert A. Lutfi

Univ. of Wisconsin, Madison, WI 53705

A COSS analysis procedure [B. G. J. Berg, J. Acoust. Soc. Am. 88, 149--158 (1990)] was used to estimate the efficiency with which 15 normal-hearing and 15 hearing-impaired listeners detected a level increment in a target tone embedded in a multitone complex. The complex was comprised of 6 oct frequencies from 250--8000 Hz and the target tone was selected as either the 250-, 1000-, or 4000-Hz tone. The hearing-impaired listeners had moderate, sloping, high-frequency sensorineural hearing impairments. Two efficiency measures were used to account for the listeners' less than ideal performance on the task; weighting efficiency ((eta)[sub wgt]), which measures how well the listener attends to or weighs the target, and noise efficiency ((eta)[sub noise]), which accounts for all other factors unrelated to weights. Weighting efficiencies were significantly higher for hearing-impaired listeners than normal-hearing listeners for the 4000-Hz target, which was in the region of hearing loss. No significant (eta)[sub wgt] differences between normal-hearing and hearing-impaired listeners were observed for the other two target tones. Even though hearing-impaired listeners sometimes weighted information more efficiently than normal-hearing listeners their overall performance on the task was significantly poorer as was reflected by smaller values of (eta)[sub noise].