Learning to Accommodate Variation in Speech Input

为了成为流利的母语说话者和听者，孩子们最终必须感知并产生与当地方言一致的语音。例如，加拿大卡尔加里的英语发音与宾夕法尼亚州匹兹堡的英语发音略有不同。这两种英语环境中的差异是有规律的，在学习语言的过程中，孩子们必须掌握这些规律。似乎与此不一致的是，儿童还必须保持一定的灵活性，将语音映射到意义上。例如，婴儿有时会遇到说话的人，他们的讲话严重偏离了他们所在社区的方言规范，就像来自意大利的非母语人士用英语讲话时一样。因此，在学习当地方言的规范模式的同时，儿童还必须保持足够的认知灵活性，以适应不属于这些规范的说话者。婴幼儿如何在语言学习中完成这些看似相互竞争的任务？回答这个问题将揭示儿童在多个时间尺度上学习的一般特征：从对短暂语音的自发解释，到短期适应，到偏离预期，再到对当地方言规律的长期学习。这项研究绘制了婴儿在与成年人的不同社会互动中暴露在母语语言环境中的声学可变性范围。它将创建一个详细的有声语音生成语料库，用来了解幼儿语言学习者面临的挑战。该研究还将研究婴幼儿的言语知觉如何受到当地方言规律的影响，揭示对方言规范的长期敏感性和对偏离方言规范的短期适应的机制。它还将调查幼儿不断增长的词汇量如何影响对口语变化的适应。这项研究采用了一种创新的跨学科方法来解决这些问题。了解英语语音结构知识的早期发展及其与发展中词汇的相互作用，将有助于我们理解典型的语言发展。它还将加深我们对多语言学习环境中口音发展和早期交际缺陷的理解。该项目的一个重要成果将是传播语音语料库，为其他研究人员提供丰富的语音样本用于研究英语方言。

To become fluent native speakers and listeners, children ultimately must perceive and produce speech that is consistent with the local dialect. For example, English spoken in Calgary, Canada sounds slightly different than English spoken in Pittsburgh, Pennsylvania. The variation in these two English environments is patterned and, in learning language, children must acquire these regularities. Seemingly at odds with this, children must also maintain some flexibility in mapping speech sounds to meaning. For example, infants sometimes encounter talkers whose speech deviates quite drastically from their community's dialectal norms, as when addressed in English by a non-native speaker from Italy. Thus, while learning the normative patterns of their local dialect, children also must maintain enough cognitive flexibility to accommodate talkers who do not fall within these norms. How do infants and toddlers accomplish these seemingly competing tasks in language learning? Answering this question will reveal general characteristics of children's learning at multiple time scales: from spontaneous interpretation of fleeting speech sounds, to short-term adaptation to deviations from expectation, to longer-term learning of the regularities of the local dialect. This research maps the range of acoustic variability to which infants are exposed in their native speech environment in different social interactions with adults. It will create a detailed acoustic speech production corpus with which to understand the challenges confronting infant language learners. The research will also study how infants' and toddlers' speech perception is shaped by regularities of the local dialect, revealing the mechanisms of long-term sensitivity to dialect norms and short-term adaptation to deviations from dialect norms. It will also investigate how toddlers' growing vocabularies influence adaptation to variability in spoken language.The research takes an innovative cross-disciplinary approach to these questions. Understanding early development of the knowledge of the sound structure of English and its interaction with developing vocabularies will contribute to our understanding of typical language development. It will also further our understanding of accent development in multilingual learning situations and early communicative deficits. An important outcome of the project will be the dissemination of a speech corpus, providing a rich acoustic sample of speech for other researchers to use in studying English dialects.