Acoustic analyses and perceptual data on anticipatory labial coarticulation in adults and children

Abstract

The present study investigated anticipatory labial coarticulation in the speech of adults and children. CV syllables, [s], [t], and [d] before [i] and [u], were produced by an adult male speaker and a female child speaker age 3 years 6 months. Each syllable was computer‐edited to include only the noise‐excited portion of fricative‐vowel stimuli and only the aperiodic portion of stop‐vowel stimuli. LPC spectra were computed for each excised segment. Analyses of the effect of the following vowel on the spectral peak associated with the second formant frequency and on the characteristic spectral prominence for each consonant were performed. Perceptual data were obtained by presenting the aperiodic consonantal segments to subjects who were instructed to identify in a forced choice paradigm the following vowel [i] or [u]. Both the acoustic and perceptual data show strong coarticulatory effects for adults and the absence of such coarticulations in the speech stimuli of the child. The results are discussed in terms of the articulatory and perceptual aspects of coarticulation in language learning.