Voice perturbations of children with perceived nasality and hoarseness.

Cycle-to-cycle variations in voice fundamental frequency (jitter) and amplitude (shimmer) were derived by electroglottography for 10 children with velopharyngeal insufficiency (VPI). Jitter was found to be positively correlated with ratings of perceived nasality, whereas shimmer was found to be positively correlated with ratings of perceived hoarseness. Theoretic implications for a regulatory model of speech aerodynamics are discussed. Additionally, clinical applications, in terms of using electroglottography as a supplemental assessment procedure, are suggested.