Effect of noise on foreign-accent adaptation

Abstract

Previous work indicates that listeners are able to adapt quickly to changes in accent [Clarke & Garrett, 2004; Bradlow & Bent, 2008] and that adaptation is faster for familiar accents [Witteman et al., 2013; Blanco et al., 2014]. The present study examines how listeners adapt to more and less familiar accents presented in noise as compared to quiet, since noisy listening environments are more perceptually challenging [Vaden et al., 2013; Gilbert et al., 2014] but also more closely represent typical listening conditions. Native English listeners heard blocks of sentences produced by native- or foreign-accented talkers (Korean, Spanish) and responded to a visual probe. Listener accuracy and reaction times were compared across accent and speaker blocks. Results showed that, unlike in quiet, listeners were unable to adapt to the less-familiar Korean accent. Processing of the familiar Spanish accent was successful in noise and quiet. Adaptation in noise was furthermore correlated with talker intelligibility: less intelligible talkers elicited lower accuracy and slower response; in quiet, there was no talker effect. The results revealed that the ability to adapt to a novel foreign accent is disrupted, as the extra perceptual effort in noise prevents listeners from generalizing about systematic variability of foreign-accented features.