Effects of typicality and interstimulus interval on the discrimination of speech stimuli
Minoru Tsuzaki, Jorge A. Gurlekian · The Journal of the Acoustical Society of America · 1991
To investigate the effects of processing time and retention interval on the perceptual judgment for speech sounds, Japanese listeners were tested with the AX discrimination task in various interstimulus intervals. Speech stimuli were synthesized to comprise both typical and stypical stimulus sets. In the typical set, the standard stimulus had characteristics of the typical Japanese /aba/ sound. In the atypical set, the standard was not a good exemplar of the Japanese /aba/ sound although it was usually recognized as /aba/. The performance of the subjects was analyzed in terms of both the center and width of discriminal processes. At relatively short intervals, there was a slight tendency for the typical standard to have a smaller width score than the atypical standard. At long intervals, there was no effect of the standard stimulus. Although the center shifted to the direction of more plosive counterparts at longer intervals, there was no effect of the standard on the center of discriminal process. The results suggest that the typical standard is represented with less noise, but this advantage decreases with increases in the interstimulus interval.