Foreigner directed speech. From speech adaptation to cortical tracking of the speech register directed to non-native listeners.

Abstract

Foreigner Directed Speech (FDS) is the result of speech accommodation produced by native speakers of a certain language while addressing non-native listeners of that language. By studying FDS, we aimed to explore the intricate dynamics of native and non-native communication and its implications for effective communication and teaching. In the first chapter, we identified the FDS acoustic features, such as vowel hyperarticulation and low speech rate. Also, we observed that FDS is adjusted to meet non-native listeners¿ linguistic needs. In the second chapter, we shed light on whether FDS speech adaptations vary depending on the speaker's communicative goals and the listeners' profiles (i.e., native vs. non-native). We measure acoustic features of speakers addressing a native and a non-native listener while teaching them to write, pronounce and recognize novel words. We found that speakers adjusted acoustic features to communicative goals depending on the listener's profile. This suggests that speakers adjust speech for teaching purposes. In chapter 3, we explored whether FDS facilitates L2 word learning as compared to NDS. participants were asked to learn L2 novel words either pronounced in FDS or Native directed speech (NDS). Results showed that the FDS group learned the words better than the NDS group. These findings supported the didactic assumption of FDS. In chapter 4, we investigated the effects of exposure to FDS on continuous speech perception. EEG, namely cortical tracking of speech, allows for real-time analysis of language processing. The results suggest that FDS supports the perception of L2 speech in (and only in) non-native listeners. Also, the study highlights the importance of considering the speech register's target audience. Through this thesis, we found that speakers adjust FDS to support learning of specific L2 skills to learn, that FDS promotes L2 novel word learning, both in recognition and production. Finally, we found that FDS also promotes perception of continuous speech, as cortical tracking results suggested.