General adaptation to accented English: Speech intelligibility unaffected by perceived source of non-native accent

Foreign-accented speech commonly incurs a processing cost, but this cost can be offset when listeners are given informative cues to the speaker's purported ethnicity and/or language background. This study investigates mechanism that underlies facilitatory effect of top-down expectation, evaluating between general adaptation (an across-the-board relaxation phonetic categorization criteria) and targeted (tuning in accent-specific phonetics). In experiment 1, native speakers American English completed transcription-in-noise task with Chinese-accented sentences. All heard same voice were randomly assigned one four visual conditions: blank silhouette, European face, an East Asian or South face. Results showed although there was no significant condition, who believed speaker non-natively accented enjoyed significantly improved performance compared those reported hearing accent. Crucially, however, correctly perceived as additional benefit over some other foreign basic pattern held even primed expect congruent face-accent pairings (experiment 2). Overall, these results provide evidence for mechanism, rather than involving adjustments.