Fundamental frequency and intensity variability in young children’s speech produced at comfortable effort level

Abstract

Experiments to study speech production and clinical evaluation of speech often require that participants phonate or produce speech at a comfortable level of effort. It is necessary to know the degree of variability in fundamental frequency (F0) and intensity (SPL) across multiple test-sessions when speech is elicited in such a manner. If the intersession variability in these measures is too large, the experimental task may need to be appropriately modified. Although the variability in F0 and SPL produced at comfortable effort level across multiple sessions has been reported for normal adult speakers, no such data is available for young children. A vowel, a sentence, and four words were produced at a comfortable level by 15 males and 14 females between the ages of 3 and 4 years, on three separate days, one week apart. The F0 and SPL for these tasks were compared across the three test sessions. Results show that there were no significant differences in F0 and SPL and suggest that normal-speaking children between the ages of 3 and 4 years show the same degree of variability in their F0 and SPL as adults when asked to set their own level of comfort.