Abstract
Perception of emotional aspects of infants' vocalizations, i. e., "comfort vs. discomfort" and "calm vs. surprised," were studied in a sample of young children in Japan (N=64). Based on perceptual experiments on adults, 10 typical voice samples were selected to represent each of 4 emotional categories. A typical picture of an infant face was prepared corresponding to each emotional category. Testing for vocal perception of "comfort vs. discomfort," for instance, only the "comfort" and "discomfort" pictures were presented. After listening to ten voice stimuli for "comfort" or "discomfort," children were asked to point to the face they thought mached the stimuli. The same procedure was followed for "calm" vs. "surprised" stimuli. Even 2-year-olds could consistently make the "comfort vs. discomfort" contrast in the same way as adults, and the proportion of matches increased with age. For the "calm vs. surprised" contrast, however, only 2-year-old children could consistently make judgments in the same way as adults, while 3-and 4 year-olds could not. These findings suggest that perception of "comfort vs. discomfort" in infants' vocalizations are easy even for 2-years-old children, while perception of the "calm vs. surprised" contrast is not fully developed in early childhood.
