Variations in relationship between fundamental frequency and intensity in speech of children during development

Abstract

Prosody development provides insight into the development of a highly specialized system that is unique to humans. Prosody is mainly encoded by regulating the fundamental frequency, intensity and duration of various tokens during discourse construction. Interplay between the fundamental frequency and the intensity plays a crucial role in formulating prosody and adult speakers modulate these parameters to produce rhythmic sentences. However, it is not known, how this relationship between these two parameters evolve with age in the children. The present study tries to fill this gap partially by investigating the statistical nature of the correlation between fundamental frequency and intensity in the speech of 42 children and 25 adults between the ages of 4–25 years. Statistically significant differences were found in the distributions of correlations between children and adults. The difference can be attributed to evolving skills of children in encoding prosodic cues through modulation of intensity by alterations in flow of air from the lungs and controlling the vibrations of vocal folds.