Karen A. Doherty

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OBJECTIVE The purpose of this study was to determine the maximum benefit provided by a time-frequency gain-manipulation algorithm for noise-reduction (NR) based on an ideal detector of speech energy. The amount of detected energy necessary to show benefit using this type of NR algorithm was examined, as well as the necessary speed and frequency resolution(More)
OBJECTIVE The purpose of the present study was to evaluate the relationship between cognitive function, listening effort, and speech recognition for a group of younger and older adults with normal hearing and a group of older adults with hearing impairment in various types of background maskers. The authors hypothesize that, as the masker condition becomes(More)
OBJECTIVES The purpose of the present study was to evaluate the effect of a noise-reduction (NR) algorithm on the listening effort hearing-impaired participants expend on a speech in noise task. DESIGN Twelve hearing-impaired listeners fitted with behind-the-ear hearing aids with a fast-acting modulation-based NR algorithm participated in this study. A(More)
PURPOSE To assess experienced hearing aid users' ability to use their hearing aids correctly. METHOD In this study, we developed the Practical Hearing Aid Skills Test (PHAST) to objectively test a hearing aid user's ability to manipulate his or her hearing aids. The PHAST requires hearing aid users to perform 8 hearing aid care and use tasks that are(More)
The purpose of this study was to determine if it is feasible to use the correlational method (Lutfi, 1995; Richards and Zhu, 1994) to estimate how listeners use or weight the information contained within various frequency bands of speech. Three naturally spoken vowel-consonant-vowel (VCV) syllables (/aba/, /aga/, and /ada/) were presented monaurally to(More)
A conditional-on-a-single-stimulus (COSS) analysis procedure [B. G. Berg, J. Acoust. Soc. Am. 86, 1743-1746 (1989)] was used to measure the weight or relative reliance that normal-hearing and hearing-impaired listeners give to different frequencies in the discrimination of the overall level of a multitone complex. On each trial, two multitone-tone complexes(More)
A conditional-on-a-single-stimulus (COSS) analysis procedure [B. G. Berg, J. Acoust. Soc. Am. 86, 1743-1746 (1989)] was used to estimate how well normal-hearing and hearing-impaired listeners selectively attend to individual spectral components of a broadband signal in a level discrimination task. On each trial, two multitone complexes consisting of six(More)
The purpose of this paper is to introduce a new signal-processing strategy, spatiotemporal pattern correction (SPC), that is based on our knowledge of the level-dependent temporal response properties of auditory nerve fibers in normal and impaired ears. In normal-hearing listeners, tuning is sharp for low-level inputs and broadens as input level increases.(More)
Untreated hearing loss can interfere with an individual's cognitive abilities and intellectual function. Specifically, hearing loss has been shown to negatively impact working memory function, which is important for speech understanding, especially in difficult or noisy listening conditions. The purpose of the present study was to assess the effect of(More)
Listeners' ability to understand speech in adverse listening conditions is partially due to the redundant nature of speech. Natural redundancies are often lost or altered when speech is filtered, such as done in AI/SII experiments. It is important to study how listeners recognize speech when the speech signal is unfiltered and the entire broadband spectrum(More)