Effects of speaking rate on temporal patterns of English

Individual subjects have been found to show considerable variation in the extent to which they manifest certain temporal patterns of English in their speech. Because at least some differences across speakers appear to be related to the fact that some subjects typically talk faster/slower than others, the present investigation examined variability in temporal patterns by having subjects produce target stimuli in sentences spoken at normal and fast rates. The results from these manipulations of speaking rate generally supported previous findings related to temporal patterns as a function of 'natural' variations in rate of speech. That is, there was considerable variability among the 15 subjects in the normal speaking rate condition in the extent to which temporal parameters such as final-syllable vowel lengthening occurred. In addition, there was substantial variation in these parameters in the fast speaking rate condition, and some systematic changes in certain patterns also occurred as a function of the rate change. For example, vowel lengthening preceding voiced obstruents tended to decrease when subjects spoke at a fast versus a normal rate, whereas phrase-final vowel lengthening was typically greater when they spoke at a faster rate.