| Abstrakt: |
Perceptual units for category identification of infant cries have been studied. Three cry categories discussed in this paper are the hunger cry, the call cry (i.e., cry calling for infant-mother interaction), and the anger cry. The original samples have been classified into these three categories. In order to generate stimuli to be used in the perceptual experiments, each of the cry samples is first segmented into single-segment units according to breath groups of the cry samples. Next, the single-segment units are combined with each other in temporal order to generate two-, three-, five-, and seven-segment unit stimuli. In addition to the multisegment unit stimuli thus obtained, the single-segment units and the three original samples are used as one-segment unit stimuli and full-segment unit stimuli, respectively, in the perceptual experiments. In identifying the cry stimuli, subjects are instructed to make a forced choice among the three cry categories. The experimental results show that category identification rates are greatly dependent upon the number of segments making up each stimulus. However, the identification rates are temporarily saturated at two-segment units in the call cry and at three- to five-segment units in the hunger and anger cries. This fact indicates that the units with two to five segments are the perceptual units. Temporal duration of the perceptual units across all three categories is similar (i.e., about 6-8 s). [ABSTRACT FROM AUTHOR] |
