Effects of dialect exposure on allophonic processing

Dialects contain different allophonic systems, potentially influencing listeners’ cognitive representations of speech sounds. I am interested in what speech perception and processing data can reveal about the nature of phonological innovation and change in allophonic systems. I report on data from two laboratory phonological studies that examine how dialect exposure to dialect-specific allophonic variation affects listeners’ perception and processing of these variants. Both studies focused on dialect-specific allophonic variation in two vowels, /æ ai/. I contrast listeners from northeastern Ohio in the Northern dialect region, a region with less /æ/ allophony (due to trap raising) and more /ai/ allophony (due to Canadian raising), with listeners from central and southwestern Ohio in the Midland dialect region, a region with more /æ/ allophony and less /ai/ allophony. The first study employed a perceptual similarity ratings task to investigate how exposure affects listeners’ cognitive representations of allophonic categories, with results revealing that listeners with more exposure to dialect-specific allophonic variation for a vowel perceived mismatching allophones to be more like mismatching phonemes than listeners with less exposure. The second study used a visual-world eye-tracking task to investigate how exposure affects lexical processing, with results revealing that exposure confers a processing advantage by reducing lexical competition among words containing different allophones. Exposure affects how listeners develop and apply phonological and lexical contrasts during speech perception.