Tremblay Annie, Namjoshi Jui, Spinelli Elsa, Broersma Mirjam, Cho Taehong, Kim Sahyang, Martínez-García Maria Teresa, Connell Katrina
Department of Linguistics, University of Kansas, Lawrence, Kansas, United States of America.
Department of French and Italian, University of Illinois, Urbana, Illinois, United States of America.
PLoS One. 2017 Jul 24;12(7):e0181709. doi: 10.1371/journal.pone.0181709. eCollection 2017.
This study investigates whether listeners' experience with a second language learned later in life affects their use of fundamental frequency (F0) as a cue to word boundaries in the segmentation of an artificial language (AL), particularly when the cues to word boundaries conflict between the first language (L1) and second language (L2). F0 signals phrase-final (and thus word-final) boundaries in French but word-initial boundaries in English. Participants were functionally monolingual French listeners, functionally monolingual English listeners, bilingual L1-English L2-French listeners, and bilingual L1-French L2-English listeners. They completed the AL-segmentation task with F0 signaling word-final boundaries or without prosodic cues to word boundaries (monolingual groups only). After listening to the AL, participants completed a forced-choice word-identification task in which the foils were either non-words or part-words. The results show that the monolingual French listeners, but not the monolingual English listeners, performed better in the presence of F0 cues than in the absence of such cues. Moreover, bilingual status modulated listeners' use of F0 cues to word-final boundaries, with bilingual French listeners performing less accurately than monolingual French listeners on both word types but with bilingual English listeners performing more accurately than monolingual English listeners on non-words. These findings not only confirm that speech segmentation is modulated by the L1, but also newly demonstrate that listeners' experience with the L2 (French or English) affects their use of F0 cues in speech segmentation. This suggests that listeners' use of prosodic cues to word boundaries is adaptive and non-selective, and can change as a function of language experience.
本研究调查了人们在晚年学习的第二语言的经历是否会影响他们在人工语言（AL）切分中使用基频（F0）作为单词边界线索的情况，尤其是当第一语言（L1）和第二语言（L2）之间的单词边界线索相互冲突时。F0在法语中表示短语结尾（进而单词结尾）的边界，但在英语中表示单词开头的边界。参与者包括功能上为单语的法语听众、功能上为单语的英语听众、L1为英语L2为法语的双语听众以及L1为法语L2为英语的双语听众。他们完成了AL切分任务，其中F0表示单词结尾的边界，或者没有单词边界的韵律线索（仅单语组）。在听完AL后，参与者完成了一项强制选择单词识别任务，其中干扰项要么是无意义音节，要么是部分单词。结果表明，单语法语听众在有F0线索时的表现比没有此类线索时更好，但单语英语听众并非如此。此外，双语状态调节了听众对单词结尾边界的F0线索的使用，双语法语听众在两种单词类型上的表现都不如单语法语听众准确，但双语英语听众在无意义音节上的表现比单语英语听众更准确。这些发现不仅证实了言语切分受L1调节，还首次表明听众对L2（法语或英语）的体验会影响他们在言语切分中对F0线索的使用。这表明听众对单词边界的韵律线索的使用是适应性的且非选择性的，并且会随着语言体验而变化。
