James J. Mahshie
Dept. of Audiol. and Speech-Language Pathol., Gallaudet Univ., 800 Florida Ave., NE, Washington, DC 20002
Recent research suggests that deaf speakers often exhibit context-dependent changes in speech articulation [for example, Mahshie et al., ASHA 32 (10), 183 (1990)]. However the coarticulatory patterns of deaf speakers are not always comparable to those of normal-hearing speakers. Furthermore, it is likely that deaf individuals exhibit differences among themselves in both the nature and extent of coarticulation--differences that may affect intelligibility. The purpose of the present study was to examine and compare lingua-palatal coarticulation evidenced by normal-hearing speakers and by deaf speakers differing in overall speech intelligibility. Three normal-hearing subjects, one intelligible deaf subject, and one semi-intelligible deaf subject produced multiple iterations of bisyllabic and trisyllabic words. Test words contained the lingua-alveolar target segments /t/ or /n/ followed by either the neutral vowel /(schwa)/ (e.g., ``tana'') or the velar consonant /k/ (e.g., ``tancat''). Palatometric measures were used to compare lingua-palatal contact patterns during production of the target consonants in the vowel and consonant contexts. Results showed that the intelligible deaf speaker, like the three normal-hearing subjects, exhibited context-dependent changes in articulation of the target segments, while the semi-intelligible deaf subject showed little evidence of anticipatory coarticulation. Possible motor organization strategies employed by the deaf subjects will be discussed.