Auditory free classification of nonnative speech by nonnative listeners

Abstract

Nonnative listeners are less accurate than native listeners at classifying talkers by regional dialect [Clopper and Bradlow (2009)]. This decrement may be due to less robust knowledge about the underlying sound structure of the target language or less extensive experience with socio-cultural phonetic variation in the target language. To disentangle the contribution of these two factors, this study examined native and nonnative listeners’ abilities to classify talkers who varied on another sociophonetic dimension: foreign accent. Unlike regional dialect variation, nonnative listeners typically have more experience with nonnative speech than native listeners, particularly for talkers with the same native language background. Using auditory free classification, native listeners of English and native Korean listeners classified talkers by perceived native language. Talkers consisted of nonnative talkers from six native language backgrounds and native talkers. Results demonstrated that native listeners were nearly perfect at grouping the native talkers together, but Korean listeners were much less accurate. Further, Korean listeners did not show an advantage for grouping Korean-accented talkers together. These results suggest that nonnative listeners’ less robust linguistic representations of the target language can hinder their abilities to attend to the acoustic-phonetic features that index dialect and accent categories. [Work supported by NIH-NIDCD Grant R21DC010027.]