Pitch and amplitude perturbations in 10 years old children

Abstract

Variations in pitch and amplitude is an essential aspect of normal voice. This normal variations (perturbations) in the voice can be grouped into voluntary perturbations (intonational) and involuntary perturbations(pitch perturbation-jitter and amplitude perturbation-shimmer). These involuntary perturbation measurements are quantified by different parameters such as absolute jitter, jitter factor, jitter ratio, directional jitter and similarly shimmer (dB), directional shimmer and amplitude perturbation quotient etc.