DEVELOPMENT OF LAUGHTER AND PROTOPHONES IN THEIR COMPLEXITY IN FORM AND FUNCTION

早期发育包括在语言中起关键作用的发声，即笑声和原声（语言前的发声）。笑是一种重要的交流工具，在生命的几个月后出现（Ruch & Ekman, 2001），后来，它将在日常对话中使用（Vettin & todt, 2004）。就像语言一样，随着时间的推移，它从原始形式演变而来（Kret et al., 2021）。在成人中，它与言语是协调的，因为它不是随机出现在句子中间，而是标点符号。原音素被认为是言语的先驱，因为它们的发育阶段导致更精细的类似言语的声音（Nathani, et al. 2006）。此外，这种模式的任何剧变通常会导致未来的语言障碍（Oller et al., 1999）。有趣的是，没有研究调查婴儿是如何开始用原始音素协调笑声的，也没有研究调查这些发声形式的复杂性是否与它们功能的复杂性同时进化。本项目旨在研究不同文化和年龄群体的原音和笑声在形式和功能上的复杂性。第一个目的是通过传统的声学分析来研究笑声和原音的声学形式，并测试它们在发展过程中的共性和差异。第二个目的是研究这些发声发生和共同发生的行为和情感背景，以及它们的个体发生在多大程度上可能发生变化。我假设笑声在形式和功能上的变化在开始与原音素协调时被重塑。

Early development includes vocalizations that play a key role in language, i.e., laughter and protophones(pre-linguistic vocalizations). Laughter is an important communicative tool which appears after a fewmonths of life (Ruch & Ekman, 2001), and which, later, will be daily used within conversations (Vettin &Todt, 2004). Just as language, it evolves over time from a primal form (Kret et al., 2021). In adults, it iscoordinated with speech as it does not occur randomly in the middle of sentences, but punctuatesspeech (Provine, 1993). Protophones are considered to be the precursors to speech since they followdevelopmental phases leading to more refined speech-like sounds (Nathani, et al. 2006). In addition, anyupheaval of this pattern usually causes future language disorders (Oller et al., 1999). Interestingly, nostudies examined how infants start to coordinate laughter with protophones nor whether the complexityin form of these vocalisations evolves concurrently as their complexity in function.This project aims to study the complexity of protophones and laughter in both the form and function,across cultural and age groups. The first aim is to examine the acoustic form of laughter andprotophones with traditional acoustic analyses and to test for commonalities and differences in theirdevelopment. The second aim is to examine in which behavioural and emotional contexts thesevocalizations occur and co-occur and to what extent there may be changes in their ontogeny. Ihypothesize that laughter variation in both form and function becomes reshaped when starting to becoordinated with protophones.