The developmental precedency of spectral and temporal cues in the perception of the /r-w/ phonemic contrast.

Abstract

The present study examined acoustical and developmental influences on the categorical perception of /r/ and /w/. One group of adults, and three groups of normally developing preschool children, aged 3, 4, and 5 years, respectively, participated in three experimental conditions. These conditions involved performing a video-game identification task employing three different synthetic ‘‘rock-walk’’ continua. In condition I, the acoustic tokens varied according to both spectral and temporal cues; in condition II, the acoustic tokens varied only with respect to spectral cues; in condition III, the acoustic tokens varied only with respect to temporal cues. As hypothesized, changes in perceptual responses were seen as a function of both age and acoustical cue availability. Temporal cues, relative to spectral cues appeared to be the more salient cue for 3 yr olds, whereas for the 4 yr olds, 5 yr olds, and adults the two types of cues appeared to be equally salient. Other developmental trends evidenced included findings that children, relative to adults, demonstrate greater /r/ perceptual categories, more variable perceptual performance, and a tendency to base their phonemic categorizations on primarily only one cue.