Cue weighting of static and dynamic vowel properties in children versus adults

Abstract

The purpose of this study was to determine whether children give more perceptual weight than do adults to dynamic spectral cues versus static cues, when identifying vowel sounds. Three experimental stimulus sets were presented, each with 30-ms stimuli. The first consisted of unchanging formant onset frequencies ranging in value from frequencies for [i] to those for [ɑ], corresponding to a bilabial stop consonant. The second two consisted of either an [i] or [ɑ] onset frequency with a 25-ms portion of a formant transition whose trajectory was toward one of a series of target frequencies ranging from those for [i] to those for [ɑ]. Ten children between the ages of 3;8 and 4;1 and a control group of 10 adults identified each stimulus as [bi] or [bɑ]. The results showed developmental effects: the children relied more heavily than the adults did on the static formant onset frequency cue to identify the vowels, while the adults appeared to give more equal weight to both static and dynamic cues than the children did. These findings contradict the Developmental Perceptual Weighting Shift theory and are discussed in relation to this theory and other current research on the development of vowel perception.