Laryngeal‐oral coordination in the production of obstruents by hearing impaired speakers

Abstract

The study examines the organization of laryngeal control and inter‐articulator timing in the production of voiceless obstruents by hearing impaired speakers. Three severe‐profoundly deaf adults served as subjects. Laryngeal activity was monitored by trans‐illumination; temporal patterns of oral articulation (lips and tongue‐palate) were recorded using an electrical transconductance technique. For each of the deaf speakers, an inappropriate abduction gesture immediately preceded production of the test word, a pattern never observed for hearing speakers. However, the deaf speakers differed from each other with respect to type of errors, variability, and interarticulator coordination. For the more intelligible deaf speaker, the timing of glottal opening with respect to oral articulation was most like that observed for normals. The second deaf speaker often failed to observe voicing contrasts with respect to glottal opening; that is, he failed to produce an opening gesture for voiceless obstruents as normals. For the third deaf speaker, the pattern of errors appears to be more complex including both missing and inappropriate glottal opening gestures. Data will be discussed with respect to listener judgments. [Work supported by NINCDS and BRSG.]