One reason that word learning presents a challenge for children is because pairings between word forms and meanings are arbitrary conventions that children must learn via observation - e.g., the fact that "shovel" labels shovels. The present studies explore cases in which children might bypass observational learning and spontaneously infer new word meanings: By exploiting the fact that many words are flexible and systematically encode multiple, related meanings. For example, words like shovel and hammer are nouns for instruments, and verbs for activities involving those instruments. The present studies explored whether 3- to 5-year-old children possess semantic generalizations about lexical flexibility, and can use these generalizations to infer new word meanings: Upon learning that dax labels an activity involving an instrument, do children spontaneously infer that dax can also label the instrument itself? Across four studies, we show that at least by age four, children spontaneously generalize instrument-activity flexibility to new words. Together, our findings point to a powerful way in which children may build their vocabulary, by leveraging the fact that words are linked to multiple meanings in systematic ways.

The CEGA Working Paper Series showcases ongoing and completed research by faculty affiliates of the Center. CEGA Working Papers employ rigorous evaluation techniques to measure the impact of large-scale social and eco-nomic development programs, and are intended to encourage discussion and feedback from the global development community.

Empirical audit and review is an approach to assessing the evidentiary value of a research area. It involves identifying a topic and selecting a cross-section of studies for replication. We apply the method to research on the psychological consequences of scarcity. Starting with the papers citing a seminal publication in the field, we conducted replications of 20 studies that evaluate the role of scarcity priming in pain sensitivity, resource allocation, materialism, and many other domains. There was considerable variability in the replicability, with some strong successes and other undeniable failures. Empirical audit and review does not attempt to assign an overall replication rate for a heterogeneous field, but rather facilitates researchers seeking to incorporate strength of evidence as they refine theories and plan new investigations in the research area. This method allows for an integration of qualitative and quantitative approaches to review and enables the growth of a cumulative science.

Belief in supernatural beings is widespread across cultures, but the properties of those beings vary from one culture to another. The supernatural beings that are part of Hinduism, for instance, are represented as human-like, whereas those that are part of Islam are represented more abstractly. Here, we explore how children exposed to both types of representations conceptualize the relevant beings. We administered several measures of anthropomorphism to Hindu and Muslim children (n = 124) from a religiously-diverse community in India. Participants consistently anthropomorphized fictional beings (ghosts and fairies) and Hindu beings (Ganesha and Krishna) but varied in their anthropomorphization of Islamic beings (Muhammad, Allah). Younger participants (aged 8 to 11) anthropomorphized Islamic beings more than older participants (aged 12 to 15), and Hindu participants anthropomorphized them more than Muslim participants. These findings suggest that children initially anthropomorphize supernatural beings but can learn to conceptualize them more abstractly if encouraged by cultural input. They also suggest that abstract conceptions of divine agents are not a universal endpoint in the development of religious cognition.

Three studies investigated preschoolers' self-directed learning ability in a naturalistic context: learning from overheard speech. In Experiment 1, 4.5-to 6-year-olds were exposed to 4 novel words and 6 arbitrary facts corresponding to a set of copresent toys; in Experiment 2, 3-to 4.5-year-olds heard 5 nouns and 3 facts. In the Pedagogical conditions, children were taught the information with the aid of multiple pedagogical cues, but in the Overhearing conditions, children had to listen in to one side of a phone call to learn the information. Older preschoolers (Experiment 1) learned all items above chance in both conditions. Younger preschoolers (Experiment 2) learned words and facts above chance in the Pedagogical condition but were at chance at learning words in the Overhearing condition, despite reliably learning facts from overhearing. Experiment 3 demonstrated that younger children's difficulty at learning new words from overhearing could not be explained by only being able to hear one side of the phone conversation, as they similarly struggled when the phone call took place over speakerphone. Measures of children's touch behavior suggest that older children were better able to coordinate their attention between the overheard speech and objects, though even younger children showed evidence of attention to the overheard speech. Together, our results demonstrate that by age 5, children can learn multiple new words and facts via overhearing. This self-directed learning ability depends on being able to coordinate attention between speech and the surrounding environment, a capacity that develops throughout preschool.

Parents with fewer educational and economic resources (low socioeconomic-status, SES) tend to speak less to their children, with consequences for children’s later life outcomes. Despite this well-established and highly popularized link, surprisingly little research addresses why the SES “word gap” exists. Moreover, existing research focuses on individual-level explanations with little attention to structural constraints with which parents must contend. In two pre-registered studies, we test whether experiencing financial scarcity itself can suppress caregivers’ speech to their children. Study 1 suggests that caregivers who are prompted to reflect on scarcity—particularly those who reflect on financial scarcity—speak to their 3-year-olds less than a control group in a subsequent play session. Study 2 finds that caregivers speak less to their children at the end of the month—when they are more likely to be experiencing financial hardship—than the rest of the month. Thus, above and beyond the individual characteristics of parents, structural constraints may affect how much parents speak to their children.

Linguistic alignment—the contingent reuse of our interlocutors' language at all levels of linguistic structure—pervades human dialogue. Here, we design unique measures to capture the degree of linguistic alignment between interlocutors' linguistic representations at three levels of structure: lexical, syntactic, and semantic. We track these measures in a longitudinal dataset of early conversations between caregivers and children with and without perinatal brain injury. Specifically, we test the predictions of the well-known Interactive Alignment Model, taking advantage of the variability within our sample in terms of the strength of interlocutors' linguistic representations, whether owed to age or injury. Ultimately, we find inconsistent support for the (largely untested) predictions of the Interactive Alignment Model, pointing to a need for new quantitative accounts of the mechanisms underlying linguistic alignment. Our results regarding the trajectory of interactive alignment broadly replicate developmental trends documented by other researchers, though analyses linking concurrent vocabulary and child alignment, as well as caregiver alignment and later child vocabulary—defy predictions from previous work. Our goal with these analyses is to start a conversation regarding the mechanisms underlying linguistic alignment, and to inform theories of how interactive linguistic experience supports language development.

Recent evidence suggests that children play an active role in their own learning in many domains, yet the study of language development has typically cast children as passive recipients of adult guidance. We argue that this approach overlooks language learning as a fruitful domain in which to explore children’s active, self-directed learning — specifically, instances where children seize language learning opportunities and/or select the linguistic information they want to receive, thereby enhancing their own learning. We suggest that reframing the child as an active language learner introduces novel explanations for key phenomena in language development, and offers researchers complex, ecologically valid tests of rational learning accounts.