Formant movement and duration in second-language vowel learning

Abstract

This study tested native speakers of Norwegian, German, French, and Spanish on their recognition and production of L2 English vowels. A goodness-optimization method was used to construct phonetically detailed perceptual vowel space maps for each listener’s L1 and L2 (English). These maps comprised best exemplar locations in a multidimensional stimulus space that included F1 and F2 target frequencies, F1 and F2 movement, and duration. The maps were then compared to assessments of each individual’s recognition accuracy for naturally spoken English vowels and their degree of accent for spoken English. The results demonstrated that all four language groups used phonetic detail to recognize English vowels; individuals had higher recognition accuracy for natural English vowels when their best exemplars had formant movement and duration contrast that were more like those of L1 English speakers. However, their use of phonetic detail was not entirely predictable by their L1 background. It thus appears that individuals with a range of L1 backgrounds form phonetically detailed category representations during L2 learning, and that their representation of phonetic detail has practical implications for recognizing natural L2 speech.