Deaf Children's Use of Mutual Exclusivity and Eye Gaze to Determine Word Meanings in American Sign Language

When determining the meaning of new words, young children have a variety of cues available to them. Two types of such cues are referential attention (e.g., gaze and point cues), and lexical constraints, such as mutual exclusivity biases. This is likely also true for deaf children acquiring American Sign Language (ASL), however, the visual modality of the language and the variation in individual early language experience may affect the extent to which they prioritize these cues in ways that are different from hearing children acquiring spoken language. In the current study, we examined the relative use of gaze following and mutual exclusivity to learn new signs in a sample of young deaf children (ages 20-60 months) acquiring ASL. In a behavioral two alternative forced-choice paradigm, children were asked to choose between two objects (one familiar, one novel) using a prompt with a gaze cue, a novel sign, or both cues in conflict. Our findings demonstrate that young deaf children recruit mutual exclusivity in determining referent labels if their early language experience is primarily monolingual in ASL, while those who were bimodal bilingual in ASL and spoken English showed less clear preferences. Children did not show a clear preference for gaze cues or mutual exclusivity when the two cues were presented in conflict. This study informs our understanding of the language acquisition process in ASL and provides further evidence for accounts of how children learning language across modalities recruit referential versus lexical cues to support word learning. SUMMARY: Deaf children acquiring American Sign Language demonstrated a mutual exclusivity bias when mapping novel signs to novel objects. Bimodal bilingual children (acquiring ASL and English) were not as clear in their use of mutual exclusivity relative to monolingual (acquiring ASL only) peers. Children relied on adult gaze as a reliable referential cue, particularly in the monolingual group, and this strengthened with age. Children did not show a clear preference for gaze or linguistic cues when the two were presented in conflict.