Development of Speech Perception and Brain Plasticity

描述（申请人提供）：语言是人类的标志。在过去的50年里，关于语言的争论已经让位于一种关于人类习得语言过程的新观点。对婴儿的实证研究是理论变革的催化剂之一。在过去的十年里，研究人员不仅绘制了婴儿何时获得母语知识的图表，还绘制了他们如何获得母语知识的图表，这引起了语言学和心理学理论的修订。新的研究集中在语音的语音单位，即构成单词的辅音和元音。该实验室的主要进展是跨语言数据，显示婴儿在发育的早期阶段通过接触语言来学习，这改变了语言感知以帮助语言学习。此外，我们的研究表明，早期的语言预示着后来的语言，母亲对婴儿定向语言的清晰程度与婴儿的语言感知能力有关。最后，对婴儿和成人听语言的大脑测量表明，在早期发育过程中，婴儿的大脑“神经上承诺”母语语言的模式，这既促进了未来的语言学习，也促进了在生命第一年末发生的非母语语言感知的下降。这项关于早期语言感知的工作正在影响儿童发展、神经科学、神经生物学和计算建模。作为这个项目的一部分，早期语言测量被用于包括自闭症在内的发育性残疾的研究，并可能提供残疾的早期标志。这些数据促进了母语磁铁模型的扩展，将神经承诺作为发展变化的机制。这一理论立场为本文的研究提供了背景和框架。为了验证这一理论，进一步提高我们对婴儿语言发展的认识，我们提出了四条研究方向：(a)语音感知发展及其对语言的影响；(b)大脑与早期言语和语言发展的关系，(c)语言输入对儿童的作用，以及(d)大脑可塑性和语言习得的“关键期”。这项研究将提供数据，以解决语音和语言发展的理论，以及生物学和文化之间界面的更一般的理论。

DESCRIPTION (provided by applicant): Language is a hallmark of human beings. In the last 50 years, debates on language have given way to a new view of the process by which humans acquire language. One catalyst for theoretical change has been empirical studies on infants. In the last decade, researchers have not only charted when infants acquire knowledge about the properties of their native language, but how they do so, and this has caused a revision in linguistic and psychological theories. New research focuses on the phonetic units of speech, the consonants and vowels that form building blocks for words. Key advances from this laboratory are cross- language data showing that infants learn from exposure to language in the earliest periods of development and that this alters speech perception to assist language learning. Moreover, our studies show that early speech predicts later language, and that the clarity of mothers' infant-directed speech is linked to infants' speech perception abilities. Finally, brain measures on infants and adults listening to language suggest that, during early development, the infant brain "neurally commits" to the patterns of native language speech and that this both promotes future language learning as well as the decline in nonnative speech perception that occurs at the end of the first year of life. This work on early speech perception is impacting child development, neuroscience, neurobiology, and computational modeling. The early speech measures developed as a part of this project are being used in the study of developmental disabilities including autism, and may provide an early marker of the disability. The data prompted an extension of the Native Language Magnet model to incorporate neural commitment as the mechanism for developmental change. This theoretical position provides the background and framework for the studies in this proposal. Four converging lines of research are proposed to test the theory and further advance our knowledge of infant speech development: (a) speech perception development and its impact on language; (b) the brain correlates of early speech and language development, (c) the role of language input to children, and (d) brain plasticity and the "critical period" for language acquisition. The research will produce data that address theories of speech and language development and more general theories of the interface between biology and culture.