Synthetic speech audiometry
Corine A. Bickley, Gerald D. Kidd · The Journal of the Acoustical Society of America · 1989
A new hearing test is being developed that is based on presenting to listeners sets of synthesized words with well-defined acoustics properties. The test is based in part on work by Gòsy et al. [Proc. 11th ICPS, Tallinn (1987)], and its aim is to estimate a listener's hearing sensitivity from errors in word discrimination. Sets of words have been synthesized (using the Klatt synthesizer) that differ from each other by one of two phonemes (e.g., sit sat fat fit). The synthesis was guided by two goals. (1) Each word should differ from another word in a set by only one acoustic feature; the primary difference must be limited to a specific frequency band (e.g., sit versus sat differ by the frequency of the first formant). (2) The synthesized words should be highly intelligible to normally hearing listeners in a quiet environment. Initial results were obtained by presenting the synthesized words combined with white noise of various levels in a forced-choice paradigm to normally hearing subjects,. As expected, word discriminability was correlated with the salience of the acoustic feature that distinguishes the word relative to the added noise. The feasibility of using synthesized word sets of this type to detect and estimate the severity of hearing impairment will be discussed. [Work supported by a grant from NIH.]