Lexical Development in Human Infants

921064本研究旨在揭示正常婴儿在出生后六个月内的词汇再认能力。研究的重点是在发声开始年龄之前，从流利的母亲语音中切分和提取单词(或词长单位)所需的知觉和记忆能力。一种新的熟悉-偏好(F-Pref)技术被用来评估婴儿对单词的敏感性。这项技术包括一个短暂的熟悉期(30-45秒)，在此期间，婴儿被呈现在句子中的目标词(或非词)，然后与不熟悉的词相比，测试对这些词的孤立识别。熟习后的再认表现为对熟悉的单词比不熟悉的单词听得时间更长。这项技术将被用来进一步探索7至8个月大的婴儿在周围声学、语音和语言特定语境变化、语速改变以及在熟悉期间控制停顿频率时能够从流利的语音中提取单词的条件。除了这些主要问题外，我们还将尝试将F-Pref技术扩展到出生后六个月的婴儿(使用简化的程序)和较大的婴儿，试图揭示婴儿时期语义启动的出现。由于对流利语音中嵌入的单词的切分、提取和记忆是形成词汇的必要先导，这些实验应该揭示出婴儿在语言习得的早期阶段的基本能力，当时人们认为理解优于产生。

921064 The purpose of this research is to reveal the lexical-recognition competencies of normal human infants during the second six months of postnatal development. The focus of the research is on the perceptual and memory abilities required for the segmentation and extraction of words (or wordlength units) from fluent maternal speech prior to the onset-age of vocal production. A new familiarization-preference (F-Pref) technique has been developed to assess infants' sensitivities to words. This technique involves a brief familiarization period (30-45 seconds) during which infants are presented with target words (or non-words) embedded in sentences and subsequently tested for recognition of those words in isolation compared to non-familiar words. Postfamiliarization recognition is revealed by longer listening times to familiar over non-familiar words. This technique will be used to explore further the conditions under which 7 to 8 month old infants are able to extract words from fluent speech when the surrounding acoustic, phonetic, and language-specific contexts are varied, when speaking rate is altered, and when the frequency of pauses is manipulated during the familiarization period. In addition to these primary questions, we will also attempt to extend the F-Pref technique to infants in the first six months of postnatal development (using simplified procedures), and to older infants in an attempt to reveal the emergence of semantic priming in infancy. Because the segmentation, extraction, and memory for words embedded in fluent speech is a necessary precursor to the formation of a lexicon, these experiments should reveal a fundamental capacity of infants in the early stage of language acquisition when comprehension is thought to be superior to production.