Second Biennial Hearing Aid Research and Development Conference
September 22-24, 1997
National Institutes of Health
Hearing-Impaired Listeners' Auditory and Audiovisual Word Recognition Speed: Effects of Audiological Factors
Philip F. Seitz, (Army Audiology and Speech Center, Walter Reed Army Medical Center, Washington, D.C.
The speed with which listeners recognize spoken words is potentially a measure of the attentional demands of speech listening, and might have implications for understanding individual differences in perceiving fast versus slow fluent speech. Previous research compared word recognition speed in hearing-impaired (HI) and normal-hearing (NH) subjects listening at the soft and loud extremes of their functional dynamic ranges. Irrespective of loudness level, the HI group recognized words significantly more slowly than the NH group did. The present study addressed the effects of age, pure-tone average audiometric threshold, and clinically tested word recognition on auditory and audiovisual spoken word recognition speed in 26 HI subjects. Using a set of ten different spoken words, subjects made speeded same-different classification responses to pairs of auditory and audiovisual words presented monotically at MCL, with no spectrum shaping. The dependent variable was reaction-time (RT); accuracy was nearly perfect. The most striking result was that all subjects showed faster RTs to audiovisual than to auditory stimuli. None of the audiological factors was significantly correlated with RT in either the auditory or audiovisual modality. However, amount of "audiovisual benefit"--i.e., speed-up afforded by visual speech information--showed a significant positive correlation with word recognition. These results suggest that improving a HI listener's word recognition accuracy might not lead directly to faster auditory word recognition, but could potentiate a speed-up in audiovisual word recognition.
[Research supported by the NIDCD]
Return to Conference Abstracts List