This study examines cross-generational changes in the vowel systems in central Ohio, southeastern Wisconsin and western North Carolina. Speech samples from 239 speakers, males and females, were divided into three age groups: grandparents (66-91 years old), parents (35-51) and children (8-12). Acoustic analysis of vowel dynamics (i.e., formant movement) was undertaken to explore variation in the amount of spectral change for each vowel. A robust set of cross-generational changes in /ɪ, ε, æ, ɑ/ was found within each dialect-specific vowel system, involving both their positions and dynamics. With each successive generation, /ɪ, ε, æ/ become increasingly monophthongized and /ɑ/ is diphthongized in children. These changes correspond to a general anticlockwise parallel rotation of vowels (with some exceptions in /ɪ/ and /ε/). Given the widespread occurrence of these parallel chain-like changes, we term this development the "North American Shift" which conforms to the general principles of chain shifting formulated by Labov (1994) and others.

The understanding of sociolinguistic variation is growing rapidly, but basic gaps still remain. Whether some languages or dialects are spoken faster or slower than others constitutes such a gap. Speech tempo is interconnected with social, physical and psychological markings of speech. This study examines regional variation in articulation rate and its manifestations across speaker age, gender and speaking situations (reading vs. free conversation). The results of an experimental investigation show that articulation rate differs significantly between two regional varieties of American English examined here. A group of Northern speakers (from Wisconsin) spoke significantly faster than a group of Southern speakers (from North Carolina). With regard to age and gender, young adults read faster than older adults in both regions; in free speech, only Northern young adults spoke faster than older adults. Effects of gender were smaller and less consistent; men generally spoke slightly faster than women. As the body of work on the sociophonetics of American English continues to grow in scope and depth, we argue that it is important to include fundamental phonetic information as part of our catalog of regional differences and patterns of change in American English.

Recent findings have shown that listeners' region of origin and geographic mobility affect their perception of dialect-specific properties of speech in vowel identification and dialect categorization tasks. The present study examined the perceptual dialect classification performance of four groups of listeners using a six-alternative forced-choice categorization task. The residential history of the listeners was manipulated so that the four groups of listeners differed in terms of region of origin (Northern or Midland United States) and geographic mobility (Mobile or Non-Mobile). Although residential history did not significantly affect accuracy in the categorization task, both region of origin and geographic mobility were found to affect the underlying perceptual similarity structure of the different regional varieties. Geographically local dialects tended to be confused more often than nonlocal dialects, although this effect was attenuated by geographic mobility.

Early linguistic experience has been shown to affect speech perception in a variety of ways. The present experiment investigated the effects of early linguistic experience on dialect perception. Two groups of participants listened to sentences read by talkers from six American English dialects and were asked to identify where they thought the talkers were from using a forced-choice categorization task. We found that "army brats," who had lived in at least three different states, performed better than "homebodies," who had lived only in Indiana, in terms of overall categorization accuracy. Army brats who had lived in a given region also categorized talkers from that region more accurately than army brats who had not lived there. Clustering analyses on the stimulus-response confusion matrices revealed significant differences in the perceptual similarity spaces for the two listener groups. These results suggest that early exposure to linguistic variation affects how well listeners can identify where unfamiliar talkers are from.