Infants who are rarely spoken to nevertheless understand many words

Abstract

Theories of language development---informed largely by studies of Western, middle-class infants---have highlighted the language that caregivers direct to children as a key driver of language learning. However, some have argued that language development unfolds similarly across environmental contexts, including those in which child-directed language is scarce. This raises the possibility that children adapt their learning strategies to the language available in their environments, such that some children come to rely on speech that they overhear. We explore this hypothesis with infants in an indigenous Tseltal-speaking community in Southern Mexico, who are rarely spoken to, yet overhear a great deal of other-directed language by virtue of being carried on their mothers' backs. Adapting a previously-established gaze-tracking method for detecting early word knowledge to our field setting, we find that, like Western infants, Tseltal infants exhibit implicit knowledge of high-frequency nouns (Exp. 1). Moreover, they exhibit comprehension of Tseltal honorific terms used to greet adults in the community (Exp. 2). Notably, these honorific terms represent language that could only have been acquired through overhearing, and infants' task performance demonstrates an ability to discriminate highly similar stimuli at an earlier age than has been shown among Western children. Together, these results suggest that for some infants, learning from overhearing may be an important path toward developing language.

Embracing the hidden potential: The contribution of majority world research to developmental science

“…Moreover, emic research can challenge long‐held beliefs about developmental mechanisms and provide evidence for alternative or multiple mechanisms. For example, research conducted with Tseltal families in the south of México demonstrated that infants can acquire language skills through overhearing conversations, challenging the dominant notion of child‐directed speech as a critical driver for language acquisition (Foushee & Srinivasan, 2023). In the same vein, research in collectivistic countries in the Majority World challenges the typical characteristics associated with adolescence in the more individualistic contexts in the Global North (Wang et al., 2020).…”