Ludusan Bogdan, Cristia Alejandrina, Martin Andrew, Mazuka Reiko, Dupoux Emmanuel
Laboratoire de Sciences Cognitives et Psycholinguistique, EHESS/École Normale Supérieure-PSL Research University/CNRS, Paris, France.
Laboratory for Language Development, RIKEN Brain Science Institute, Wako-shi, Japan.
J Acoust Soc Am. 2016 Aug;140(2):1239. doi: 10.1121/1.4960576.
This study explores the long-standing hypothesis that the acoustic cues to prosodic boundaries in infant-directed speech (IDS) make those boundaries easier to learn than those in adult-directed speech (ADS). Three cues (pause duration, nucleus duration, and pitch change) were investigated, by means of a systematic review of the literature, statistical analyses of a corpus of Japanese, and machine learning experiments. The review of previous work revealed that the effect of register on boundary cues is less well established than previously thought, and that results often vary across studies for certain cues. Statistical analyses run on a large database of mother-child and mother-interviewer interactions showed that the duration of a pause and the duration of the syllable nucleus preceding the boundary are two cues which are enhanced in IDS, while f0 change is actually degraded in IDS. Supervised and unsupervised machine learning techniques applied to these acoustic cues revealed that IDS boundaries were consistently better classified than ADS ones, regardless of the learning method used. The role of the cues examined in this study and the importance of these findings in the more general context of early linguistic structure acquisition is discussed.
本研究探讨了一个长期存在的假设，即婴儿导向性言语（IDS）中韵律边界的声学线索使这些边界比成人导向性言语（ADS）中的边界更容易学习。通过对文献的系统综述、对日语语料库的统计分析以及机器学习实验，研究了三种线索（停顿时长、核心音节时长和音高变化）。对先前研究的综述表明，语域对边界线索的影响并不像之前认为的那样明确，而且某些线索的研究结果在不同研究中常常存在差异。对一个包含母婴和母亲与访谈者互动的大型数据库进行的统计分析表明，停顿时长以及边界前音节核心的时长是在IDS中增强的两种线索，而f0变化在IDS中实际上有所减弱。应用于这些声学线索的监督式和非监督式机器学习技术表明，无论使用何种学习方法，IDS边界的分类始终比ADS边界更好。本文讨论了本研究中所考察线索的作用以及这些发现在早期语言结构习得更广泛背景下的重要性。
