Can we really understand speech through the skin?

Abstract

The purpose of this presentation is to (1) present longitudinal data on the speech perception abilities of profoundly hearing‐impaired adults and children who use wearable vibrotactile aids, and (2) raise issues relevant to developing improved tactile devices. Data collected to date reveal that most of the profoundly hearing‐impaired subjects in this study perceived speech better when using a seven‐channel vibrotactile aid than when they used a two‐channel device. Even with the seven‐channel instrument, the highest levels of performance were limited largely to discrimination and identification of speech features (segmental and suprasegmental) and enhanced speechreading. Whereas these are clinically significant findings, it is not clear if these results reflect perception of linguistically relevant units of speech or merely perception of acoustic events. Understanding words in sentences without visual clues would provide the most convincing evidence that speech can be understood through the skin. This level of performance has not been realized with current tactile aids. The ability of Tadoma users to understand conversational speech from feeling the articulatory movements of the talker suggests that speech understanding might be possible if devices delivered a richer speech signal to the user. This and other issues related to device development will be discussed.