Impact of Speech Input on Speech Production Learning

本研究项目关注的是发现在发育的早期阶段出现语音运动控制的机制，特别关注对可变输入的适应。长期以来，人们一直认为，由于语言运动控制的严重限制，所有的婴儿都以同样的方式咿呀学语。在nserc资助的过去十年的研究中，我们确定，学习英语、法语或阿拉伯语的婴儿在声学测量时，会发展出具有明显元音特征的咿呀学语。在这个项目中，我的目的是阐明由成人的语音输入影响婴儿的声音输出的机制。在一系列研究中，母亲和婴儿之间的声音交流将在6、8、10、12和14个月时被纵向记录下来。母亲和婴儿讲话中的元音将被声学描述，声学特征的分布将被详细绘制出来，以揭示随着时间的推移，二联体内部的收敛模式和跨语言群体的分化模式。将描述婴儿和母亲发声的瞬间到瞬间时间模式的各个方面。在第二个系列的研究中，元音输入的时间模式将相对于婴儿的声音输出进行操纵。这些研究将允许我们测试关于潜在机制的替代假设，这些机制可能解释婴儿语音发育中对语音输入声学特征的适应。这些研究将进一步加深我们对婴儿适应语言环境的正常过程的理解，也将对我们对延迟语言习得的理解产生影响。

This research program is concerned with discovering the mechanisms that underly the emergence of speech motor control in the earliest stages of development, with a particular focus on adaptation to variable inputs. It has long been thought that all infants babbled in the same way due to severe constraints on speech motor control. Over the past ten years of NSERC-funded research we established that infants learning English, French or Arabic develop babbling with distinct vowel characteristics when measured acoustically. In this project I aim to illuminate the mechanism by which the speech input from adults influences the infant's vocal output. In one series of studies, vocal exchanges between mothers and infants will be recorded longitudinally at 6, 8, 10, 12 and 14 months. The vowel sounds in the mothers' and infants' speech will be described acoustically and the distributions of acoustic characteristics will be plotted in detail to reveal patterns of convergence within dyads and divergence across language groups as they emerge over time. Aspects of the moment-to-moment temporal patterning of infant and maternal vocalizations will be described. In a second series of studies the temporal pattern of vowel inputs will be manipulated relative to infant vocal outputs. These studies will allow us to test alternative hypotheses regarding potential mechanisms that might explain adaptation to acoustic characteristics of the speech input in infant vocal development. These studies will further our understanding of the normal processes by which the infant adapts their speech production to the ambient language environment and will also have implications for our understanding of delayed speech acquisition.