Trading relations in the perception of speech by 5-year-old children.

Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the "say-stay" distinction. Identification functions were obtained for two synthetic "say-stay" continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an "ay-day" continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to "cooperate" or "conflict" phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.