The rise and fall of the soft palate: The Velotrace

The Velotrace is a mechanical device that makes possible the collection of analog data on velar position [S. Horiguchi and F. Bell-Berti, Clin. Pal. J. 24, 104–111 (1987)]. The device consists of two levers connected through a push rod, carried on a support rod. The Velotrace is positioned with the support rod resting on the floor of the nasal cavity, with one lever resting on the nasal surface of the velum. When this internal lever is deflected upward, the second (or external) lever is deflected toward the speaker; i.e., changes in the position of the lever resting on the velum are directly reflected in the changes in position of the external lever. The position of an LED fixed to the end of the external lever is monitored with an optoelectric camera, and recorded with an FM tape recorder. [Supported by NIDCD Grant No. DC-00121 to the Haskins Labs.]