The role of visual cues on word recognition in noise in monolingual and bilingual toddlers

Aims and objectives/purpose/research questions: The purpose of this study was to examine how visual speech cues impact the ability to recognize words in the presence of background noise in toddlers who vary in language exposure (i.e., being raised bilingual or monolingual). Design/methodology/approach: Seventy-two children (36 monolinguals and 36 bilinguals) between the ages of 24 and 35 months completed an online Preferential Looking task where they saw picture-pairs of familiar objects (e.g., balloon and apple) on a screen and heard sentences instructing them to locate one of the objects (e.g., look at the apple!). Speech was heard in quiet and in the presence of competing noise, and with or without visual speech cues. Data and analysis: Children’s eye movements were coded offline. We then identified the proportion of time they fixated on the correct object on the screen. Performance within and between groups was compared using linear mixed effects models. Findings/conclusions: Bilinguals performed worse than monolinguals when there was both noise and no visual speech cues present. Within group differences showed that monolinguals performed similarly in every condition while bilinguals had significantly lower accuracy in every condition compared to the easiest condition (i.e., visual speech cues present without noise). Originality: This is the first study to examine how the presence of visual speech cues impacts word recognition in noise in both monolingual and bilingual infants. Significance/implications: High noise levels are present in everyday environments and children might not always have access to visual speech cues while hearing speech. Thus, this work has implications for learning and education practices with young bilinguals. Limitations (optional): We used an indirect measure of noise in the home to explore how this related to processing in noise in a laboratory task. Future work should use a direct measure of noise in the home to further explore this.