Development of Prosodic Aspects of Speech in Early Infancy

通过声学实验和知觉实验，探讨了幼儿情感语音表达的发育变化。分析在母亲/婴儿或不熟悉的成人/婴儿的声音互动中记录的声音样本，得到以下假设。非常小的婴儿，甚至只有6到9个月大，就能发出各种各样的声音，其基本频率和强度范围都很广。2)婴儿在8 ~ 10月龄时开始出现受周围语言影响的韵律模式。然而，甚至在这几个月之前，他们就会发出各种各样的声音，这些声音可能会被成年听众视为情感表达。3)婴儿的发声可能会因与谁互动以及如何互动而发生变化。通过知觉实验分析了母婴互动中记录的婴儿发声的情感方面的细节。哭泣不包括在内。结果表明，6 - 9个月大的婴儿对表达积极情绪的词汇评分较高，如“快乐”和“快乐”。另一方面，11 - 17个月大的婴儿不仅在“快乐”和“快乐”等积极情绪词汇上得分很高，而且在“拒绝”和“愤怒”等消极情绪词汇上得分也很高。这些结果表明，婴儿在很早的年龄或咿呀学语阶段的发声包含了各种各样的声音特征，这些声音特征可能传达了各种各样的情绪表达，但那些传达负面情绪方面的声音特征可能至少在9/11月龄时仍在发展。婴儿发声的情感方面与语言组织之间的关系目前正在研究中。

Developmental changes in infants' vocal expressions of emotion were investigated via acoustical and perceptual experiments. Analyzing voice samples recorded at mother/infant or unfamiliar-adult/infant vocal interactions, the following hypotheses were obtained. 1)Very young infants, even of 6 to 9 month of age, can produce various qualities of voice with wide ranges of fundamental frequency and intensity. 2)Infants tend to emerge prosodic patterns which are influenced by their ambient language at about 8 to 10 month of age. Even before those months of age, however, they produce various voice qualities which carvmay be perceived by adult listeners as emotional expressions. 3)Infants' vocalization may change due to by whom and how they are interacted. Details of emotional aspects of infants' vocalizations recorded at mother/infant interactions were analyzed through perceptual experiments. Crying was not included. Results showed that ratings for most vocalizations recorded at 6/9 months of age were high mainly for the terms expressing positive emotions such as "amaeru" and "pleasure". On the other hand, ratings for those recorded at 11/17 months of age were high not only for positive emotional terms like "happy" and "pleasure", but also for negative emotional terms such as "refusal" and "anger. " These results indicate that infants' vocalizations at very early of age or the babbling stage contain wide variety of acoustic characteristics which may convey various emotional expressions, but those conveying negative emotional aspects without crying might still be developing at least during 9/11 months of age. Relationships between emotional aspects and linguistic organization of infants' vocalization are now being investigated.