Reduction of formant bandwidth improves vowel identification with sensorineural impairment

Accurate identification of front‐back vowels depends on the ability to locate the peak of F2. Since hearing impairment reduces frequency resolution, sensorineural hearing impaired listeners often have difficulty with certain vowel distinctions. Espinoza‐Varas, Jamieson, and Wahn [J. Acoust. Soc. Am. Suppl. 1 76, S80 (1984)] showed that (a) for normal listeners, equal changes in F2 frequency in critical‐band units produce equal changes in the judged “goodness” of vowels on front‐back vowel continua, cued by changes in F2; and (b) sensorineural impaired listeners are less sensitive to these F2 changes and less accurate in their identification of vowels. The present paper continues this work, examining whether vowel sounds can be altered to reduce masking between adjacent spectral frequencies, while preserving vowel quality. Following Assmann [J. Acoust. Soc. Am. Suppl. 1 76, S81 (1984)] we examined identification for synthesized vowels with normal versus narrow formant bandwidths. We also examined vowel ide...