Inter- and Intra-Subject Variability: A Palatometric Study Inter- and Intra-Subject Variability: A Palatometric Study

by Sanders, Marybeth Corey

Electropalatometry (EPM) has proven to be a useful clinical and research tool for measuring tongue-to-palate contact. The goal of this study was to determine whether the development of a database of standardized palatometric articulation files is feasible by examining the variability which exists within and between speakers. Twenty standard American English dialect speakers were fitted with palatometer pseudopalates. Test stimuli were VCV nonsense words using a schwa in the initial position, the 15 palatal consonants, and three corner vowels, /a/, /i/, /u/. From these palatometric recordings a variability index was created to examine intra- and interspeaker variability.

Different aspects of articulation (i.e., place, manner, voicing, coarticulation) were considered. Significant findings for variability were found for place of articulation in the /i/ vowel context and for manner of articulation in the /?/ vowel context. Also in the /a/ vowel context, significant findings were found between the commonly misarticulated /l/, /r/, and /s/. Consonants coarticulated with /a/ were found to be significantly less variable than consonants coarticulated with /u/. Also, speakers who were more variable in one vowel context, tended to be more variable in other vowel contexts. These quantitative findings, as well as qualitative observations, are discussed from theoretical and clinical perspectives. Directions for future research are outlined.