Emerging Deictic Systems Shaped by Language, Modality, and Social Interaction

To achieve social actions and coordination, we communicate different types of meanings that vary in how they relate to the world. Some form-meaning mappings are arbitrarily linked to the world, but other types of communicative forms need to be interpreted within context. This dissertation examines how we learn to integrate these various representations, focusing on deixis. The first part of this dissertation attempts to understand a long-standing theoretical question of whether pointing in signed languages has similar forms and functions as deixis in spoken languages. In Chapter 1, using naturalistic corpus data involving children communicating in spoken and signed languages, I compare the form and function of pointing and spoken pronouns over development from ages 1;06 to 4;02. Signers apply a functional analysis to their pointing in a similar way that speakers do with their deictic systems, showing similar distributions of 1) displaced references, 2) referentiality, and 3) productive combinations of deictic expressions with words. Crucially, signers' use of pointing closely resembles speakers' deictic system as a whole, encompassing both speech and gesture. Chapter 2 focuses on modality and linguistic factors influencing pointing. In sign, pointing forms are more reduced and are more likely to be slotted in the utterance compared to speech. There is no clear evidence for formational contrasts according to distinct pragmatic functions in either groups. In Chapter 3, I ask how the presence of a shared linguistic system shapes deixis by studying homesigners, deaf children who do not share a linguistic system with their parents. They develop a sophisticated system, however, a partial one relative to signers, which reveals that linguistic input may be essential for some properties of deixis to develop and not for others. Taken together, this work demonstrates that some aspects of deixis universally develop within a wide range of environments, while other functions may be linguistically mediated systems that emerge early in ontogeny.