Coarticulation Effects on the Nasalization of Vowels Using Nasal/Voice Amplitude Ration Instrumentation

Abstract

This nasal accelerometric technique shows promise for clinical assessment of articulatory details of velar function. Noninvasive techniques for quantifying the effects of velar function in speech are of special interest for clinical applications such as biofeed-back in rehabilitation and documenting the results of treatment. One promising method, using an accelerometer to detect nasalization, has been utilized by a number of investigators. In 1975, Stevens, Kalikow, and Willemain described the use of a miniature accelerometer to detect nasali— zation during speech. Subsequently, Stevens et a1 (1976) published data on peak nasal ac— celerometer signal measurements for vowels in normal and deaf speakers. They found that a small accelerometer signal could be received during non—nasalized vowel productions, but that vowels adjacent to nasal consonants had 11 to 20-dB larger peak accelerometer signal ampli— tudes than the non-nasalized vowels.