A Cineradiographic Investigations of Velar Movement Variables in Two Normals

Abstract

The purpose of this investigation was to study certain aspects of velar dynamics among normals. Two adult subjects, one male and one female, were filmed using high—speed (100 fps) lateral-view Cineradiog-raphy. Small radiopaque cups were attached to the surface of the soft palate and other articulators for tracking purposes. Trajectories of the velar fleshpoint in the midsagittal plane were demonstrated. Measures of velar velocity, velar displacement, and duration of tran— sitional movements were studied in relation to the effects of phonetic context and speaking rate variation and were compared to the activity of other articulators. Velar positioning also was studied during nasal consonant production in relation to the effects of vowel context. A familiar question asked in the cleft palate clinic is whether or not a particu— lar patient achieves velopharyngeal closure for speech and, if not, how large is the space during palatal elevation. If a patient exhibits a large velopharyn-geal space during palatal elevation, it is likely that this patient will produce speech that is characterized by hypernasality and excessive nasal emission of air. On the other hand, as suggested previously (Yules and Chase, 1968), if a speaker exhibits little or no velopharyngeal space during palatal elevation as determined by lateral-view x-rays, for example, this speaker may not necessarily be perceived as a normal speaker. Carney and Morris (1971) have shown that adult speakers judged to be hypernasal frequently exhibit velopharyngeal closure at least in the midsagittal plane during vowel production. Such closure was also reported by McWilliams, et al, (1968); but they noted loss of contact when certain patients were placed in an extended position. The results of these studies suggest that factors other than lack of velopharyn-geal closure in the midsagittal plane may be related to hypernasality in some cases. One possible factor may be that, in some patients, velopharyngeal open-Dr. Kuehn is Research Scientist with the