Contextually-relevant enhancement of non-native phonetic contrasts

Abstract

One important factor that contributes to successful speech communication is an individual’s ability to speak more clearly when their listeners have difficulty understanding their speech. Though previous studies have demonstrated that native talkers implement acoustic–phonetic speech enhancements to ensure that their speech is understood by listeners, how non-native talkers employ goal-oriented enhancements is less well-understood. Here, we examine acoustic characteristics of speech enhancements produced by native and non-native English talkers of varying proficiency. Specifically, we investigate native Mandarin learners of English. The results show that non-native talkers’ ability to enhance a specific sound contrast differed depending on their familiarity with the target English contrast from their native language experience (Mandarin), as well as their English proficiency level. These results highlight that talkers are able to enhance their speech in native and non-native languages, but also suggest that this flexibility is shaped by the talkers’ target language proficiency and the type of acoustic manipulation involved in the adaptation.