Doctoral Dissertation Research: Child Production and Comprehension of Counterfactual Wishes and Conditionals

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。诸如“如果猪有翅膀，它们就能飞”或“我希望猪能飞”之类的话语表达了一种可能性（会飞的猪），这与我们在现实世界中所知道的事实（猪没有翅膀）相反。本论文项目研究儿童如何学会产生和理解这种“反事实”的话语。为了成熟地使用反事实表达，儿童需要发展复杂的推理和复杂的语言能力。本项目旨在通过研究在推理要求相同的情况下，反事实表达的复杂性是否会影响儿童开始使用和理解反事实语言的年龄，从而理清推理和语言发展的轨迹。拟议的研究将促进我们对反事实推理的典型发展的理解，这对于高级类型的批判性思维至关重要，例如对比可能性和评估过去的事件。从这项研究中获得的知识和方法可用于进一步开发诊断工具，以识别患有发育迟缓的儿童，如自闭症谱系障碍。更具体地说，本论文研究比较了用于表达反事实意义的结构（如英语中的愿望）和不用于表达反事实意义的结构（如英语中的if/then条件句）的习得轨迹，并研究了反事实中过去时标记表达的是现在的非现实性而不是过去的时间取向这一事实所带来的习得挑战。本项目包括对儿童自发反事实产生的跨语言语料库研究（比较英语和汉语）、4- 5岁儿童反事实理解的图片选择任务和2- 3岁儿童对简单反事实话语的内隐理解的眼动追踪研究。因此，本论文通过提出语言学习中的形式-意义映射问题，补充了先前对儿童反事实推理的研究，并介绍了适用于在繁重的任务需求可能掩盖潜在能力的人群中研究反事实理解的方法。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Utterances such as "If pigs had wings, they could fly" or "I wish pigs could fly", express a possibility (flying pigs) that is in contrast with what we know to be true in the actual world (pigs don't have wings). This dissertation project investigates how children learn to produce and understand such 'counterfactual' utterances. To use counterfactual expressions in a mature manner, children need to develop both complex reasoning and complex language abilities. This project aims to disentangle the trajectories of reasoning and language development by investigating whether complexity of the counterfactual expression affects the age at which children start using and understanding counterfactual language when reasoning demands are the same. The proposed research will advance our understanding of the typical development of counterfactual reasoning, which is essential for advanced types of critical thinking such as contrasting possibilities and evaluating past events. The knowledge and methodologies obtained from this research can be used to further develop diagnostic tools to identify children with developmental delays, like autism-spectrum-disorder.More specifically, this dissertation research compares the acquisition trajectory of constructions dedicated to express counterfactual meaning (e.g. wishes in English) against constructions that are not (e.g. if/then-conditionals in English), and investigates the acquisition challenge posed by the fact that the past tense marker in counterfactuals expresses present non-actuality rather than past temporal orientation. This project consists of cross-linguistic (comparing English and Mandarin-Chinese) corpus research on children's spontaneous counterfactual productions, a picture-selection task to investigate counterfactual comprehension in 4- and 5-year-olds, and an eye tracking study to investigate 2- and 3-year-olds' implicit comprehension of simple counterfactual utterances. This dissertation thus complements prior research on children's counterfactual reasoning by raising the issue of form-to-meaning mapping in language learning and introduces methodology suitable to investigate counterfactual comprehension in populations where heavy task demands may mask underlying abilities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.