X‐ray microbeam study of velic movement

Abstract

A radio‐opaque pellet attached to the surface of an articulator and tracked with a computerized x‐ray microbeam allows generally accurate observation of the coordination of several vocal organs during speech. In cases where specific details about a single articulator are sought, the possibility of artifacts in the signal cannot be neglected. As a case in point, the movement of the velum is studied in detail. A number of minor artifacts are identified. As one example, some movement in the pellet most likely results from contact between the pellet and the posterior pharyngeal wall, not from movement of the velum per se. The magnitude of the movements attributable to artifacts is small relative to the total range of movement. Removing the effects of the artifacts allows conclusions to be drawn about the movement of the velum. As one example, descending and ascending paths of the velum appear to be slightly different. [The work reported here was performed at Bell Laboratories, Murray Hill, NJ 07974.]