Multidimensional voice program analysis in profoundly deaf children: quantifying frequency and amplitude control

Characterization of the vocal profile of profoundly deaf children using an objective voice analysis was carried out in a university-based pediatric otolaryngology clinic. 21 persons ages 3.5 to 18 years were assessed. From each sustained phonation of the vowel /a/ the following acoustic variables were extracted: fundamental frequency (F0), jitter percentage, shimmer percentage, fundamental frequency variation (vF0), peak amplitude variation (vAM), and first, second, and third formant frequencies (F1, F2, F3). Mean F0 was 267.8 Hz and consistent with established normative data. Mean measurements of jitter (0.88%) and shimmer (3.5%) were also within normal limits. The notable feature of the acoustic analysis was a statistically significant elevation in vF0 (2.81%) and vAM (23.58%). With the exception of one subject, the F1, F2, and F3 formant frequencies were comparable to those for normal hearing children. Auditory deprivation results in poor long-term control of frequency and amplitude during sustained phonation. The inability to maintain a sustained phonation may represent the partial collapse of an internal model of voice and speech.