Fundamental frequency variation in sustained vowel productions of 6‐ to 8‐year‐old children

Abstract

The purpose of this study was to determined the inherent variability of children's vocal fold vibration during sustained phonation of [a], [i], and [u]. Numerous studies (Koike, 1973; Horii, 1979) have provided normative values for the period‐to‐period variation in fundamental frequency (jitter or perturbation) in adults; however, little valid data are available for children's voices. The present investigation, unlike previous work, studied live voice productions, an approach that reduces signal distortion and measurement error. Thirty children, aged 6 through 8 years, and ten adult females participated in individual experimental sessions. Accelerometer measures (vibrometer model 501m601) of fundamental frequency (F0) and either F0 perturbation or jitter were calculated using both the Kay Elementrics Visipitch (model 6095) and cspeech software analysis program (Milenkovic, 1989). The following variables were studied: (1) vital capacity, height, weight, and gender compared to acoustic measures for children and (2) the amount of jitter (and F0 perturbation) for children versus adults. Additionally, Visipitch and CSpeech measures were correlated to observe their similarity. Results clarify whether developmental differences in the vocal fold structure of children are reflected in measures of F0 variability. Initial data will be provided for future comparison to measures from children with voice disorders.