Effects of stimulus range on the identification of distorted “R” sounds in synthesized adult and child /r-w/ confirms
Donald J. Sharf, Ralph N. Ohde · The Journal of the Acoustical Society of America · 1983
Although the perceptual reality of a distorted “R” sound has been assumed by speech pathologists, recent research using full range /r-w/ continua contradicts this assumption [D. J. Sharf and R. N. Ohde, J. Acoust. Soc. Am. Suppl. 1 72, S65 (1982)]. It is known that varying the range of stimuli in speech continua affects the perceptual categories of normally produced sounds, but it is unclear if this perceptual factor affects judgments of sounds that vary from normal to distorted production. In order to extend our knowledge of the parameters which influence the perception of distorted R, we examined the effect of varying the range of sounds in /r-w/ continua modeled after adult and child vocal tracts. In several tests, which included three repetitions of each truncated continuum and two repetitions of the full range continua, subjects identified the stimuli as R, W or distorted R. The results indicate poor identification of the ambiguous stimuli as distorted R in the full range conditions, and a decrease in their identification as distorted R in the truncated range conditions. Along with previous findings, these results cast considerable doubt on the assumption that distorted R can be distinguished from the R sound that it is intended to represent. [Work supported in part by NINCDS.]