24-Month-Olds' Selective Learning Is Not an All-or-None Phenomenon

Preschoolers modulate contrastive inferences during online language comprehension

This study examined 4- and 5-year-olds' incremental interpretation of size adjectives, focusing on whether contrastive inferences are modulated by speaker behavior. Children (N = 120, 59 females, mostly White, tested between July, 2018 and August, 2019) encountered either a conventional or unconventional speaker who labeled objects in a correspondingly typical or atypical way. Critical utterances contained size adjectives (e.g., "Look at the big duck"). With conventional speakers, gaze measures indicated that children rapidly used the adjective to differentiate members of a contrasting pair, indicating that even 4-year-olds derive contrastive inferences. With unconventional speakers, contrastive inferences were delayed in processing. The findings demonstrate that preschoolers adjust their use of pragmatic cues when presented with evidence disconfirming their default assumptions about a speaker.

20-month-olds selectively generalize newly learned word meanings based on cues to linguistic community membership

A growing body of work suggests that speaker-race influences how infants and toddlers interpret the meanings of words. In two experiments, we explored the role of speaker-race on whether newly learned word-object pairs are generalized to new speakers. Seventy-two 20-month-olds were taught two word-object pairs from a familiar race speaker, and two different word-object pairs from an unfamiliar race speaker (4 new pairs total). Using an intermodal preferential looking procedure, their interpretation of these new word-object pairs was tested using an unpictured novel speaker. We found that toddlers did not generalize word meanings taught by an unfamiliar race speaker to a new speaker (Experiment 1), unless given evidence that the unfamiliar race speaker was a member of the child's linguistic community through affiliative behaviour and linguistic competence (Experiment 2). In both experiments, generalization was observed for the word-object pairs taught by the familiar race speaker. These experiments indicate that children attend to speakers' non-linguistic properties, and this in turn can influence the perceived relevance of speakers' labels. This article is protected by copyright. All rights reserved.

Infants preferentially help individuals who label objects conventionally

Recent evidence suggests that infants engage in selective prosocial behavior toward some individuals over others; the ways in which infants are selective can illuminate the origins of prosocial behaviors. Here, we explored selective helping behavior, investigating whether a target recipient's prior adherence to, or defiance of, social conventions affects infants' subsequent likelihood of helping the target individual. 19-month-old infants (N = 120) participated in an interaction with an experimenter who correctly labeled common objects, incorrectly labeled objects, or labeled objects with nonsense English-like labels. Infants' rates of helping were higher when the experimenter adhered to labeling conventions than when she defied labeling conventions by either labeling objects incorrectly or using unfamiliar nonsense labels. The current study provides evidence that infants use information about adhering to conventions to guide their helping behavior. These findings help to document the ways in which infants are selective in their helping behavior as well as possible origins of prosocial obligations toward ingroup members.

(In)Sensitivity to Accuracy? Children's and Adults' Decisions About Who to Trust: The Teacher or the Internet

Recent research has challenged the extended idea that when presented with conflicting information provided by different sources, children, as do adults, make epistemic judgments based on the past accuracy of each source. Instead, individuals may use relatively simple, but adaptive non-epistemic strategies. Here we examined how primary-school children (N = 114) and undergraduate students (N = 57) deal with conflicting information provided by two key sources of information in their day-to-day lives: their teacher and the Internet. In order to study whether the inaccuracy of a source generated a decline in trust, we manipulated this variable between participants: teacher-wrong and Internet-wrong conditions. For this, we first presented two baseline trials, followed by the accuracy manipulation, and finally, two post-test trials. Analyses were performed on group performance as well as on individual performance, to explore the individual patterns of responses. Results revealed that most participants showed no preference for any source during baseline, with no age differences in their overall choices. Crucially, when a given source provided inaccurate information about a familiar issue, most children and adults did not lose trust on this source. We propose tentative explanations for these findings considering potential differences in the participants’ strategies to approach the task, whether or not epistemic.

I don't believe what you said before: Preschoolers retrospectively discount information from inaccurate speakers

Children use speakers' past accuracy to make inferences about novel word meanings those individuals provide in the future. An open question is whether children can retrospectively reevaluate information after learning that the source was inaccurate. We addressed this question in two experiments where a speaker first introduced labels for novel objects and then revealed that she is either accurate or inaccurate in naming familiar objects. Experiment 1 showed that 3.5- to 6.5-year-olds displayed enhanced performance on a word knowledge test when they had learned novel words from a speaker who then showed herself to be an accurate labeler as opposed to an inaccurate labeler. Experiment 2 replicated this procedure but had a different speaker provide inaccurate label information. This manipulation did not affect learning, suggesting that children discount speakers and are not simply influenced by the demands of processing inaccurate information. Together, these results indicate that 3.5- to 6.5-year-olds continue to monitor the speakers' accuracy after learning new words from them, update their beliefs as accuracy data become available, and selectively retain words learned from speakers who they deem to be epistemically competent.

Children’s Judgments of Epistemic and Moral Agents: From Situations to Intentions

Children’s evaluations of moral and epistemic agents crucially depend on their discerning that an agent’s actions were performed intentionally. Here we argue that children’s epistemic and moral judgments reveal practices of forgiveness and blame, trust and mistrust, and objection or disapproval and that such practices are supported by children’s monitoring of the situational constraints on agents. Inherent in such practices is the understanding that agents are responsible for actions performed under certain conditions but not others. We discuss a range of situational constraints on children’s early epistemic and moral evaluations and clarify how these situational constraints serve to support children’s identification of intentional actions. By monitoring the situation, children distinguish intentional from less intentional action and selectively hold epistemic and moral agents accountable. We argue that these findings inform psychological and philosophical theorizing about attributions of moral and epistemic agency and responsibility.

Eighteen-month-olds selectively generalize words from accurate speakers to novel contexts

The present studies examine whether and how 18-month-olds use informants' accuracy to acquire novel labels for novel objects and generalize them to a new context. In Experiment 1, two speakers made statements about the labels of familiar objects. One used accurate labels and the other used inaccurate labels. One of these speakers then introduced novel labels for two novel objects. At test, toddlers saw those two novel objects and heard an unfamiliar voice say one of the labels provided by the speaker. Only toddlers who had heard the novel labels introduced by the accurate speaker looked at the appropriate novel object above chance. Experiment 2 explored possible mechanisms underlying this difference in generalization. Rather than making statements about familiar objects' labels, both speakers asked questions about the objects' labels, with one speaker using accurate labels and the other using inaccurate labels. Toddlers' generalization of novel labels for novel objects was at chance for both speakers, suggesting that toddlers do not simply associate hearing the accurate label with the reliability of the speaker. We discuss these results in terms of potential mechanisms by which children learn and generalize novel labels across contexts from speaker reliability.

Intersecting Constraints on Label Learning: Effects of Age, Label Properties, and Referential Context

This research investigates the development of constraints in word learning. Previous experiments have shown that as infants gain more knowledge of native language structure, they become more selective about the forms that they accept as labels. However, the developmental pattern exhibited depends greatly on the way that infants are introduced to the labels and tested. In a series of experiments, we examined how providing referential context in the form of familiar objects and familiar object names affects how infants learn labels that they would otherwise reject, nonspeech sounds. We found evidence of the development of intersecting constraints: Younger infants (14-month-olds) were more open to learning nonspeech tone labels than older infants (19-month-olds), and younger infants were more open to the influence of referential context. These findings suggest that infants form expectations about labels and labeling contexts as they become more sophisticated learners.

Cognitive Foundations of Learning from Testimony

Humans acquire much of their knowledge from the testimony of other people. An understanding of the way that information can be conveyed via gesture and vocalization is present in infancy. Thus, infants seek information from well-informed interlocutors, supply information to the ignorant, and make sense of communicative acts that they observe from a third-party perspective. This basic understanding is refined in the course of development. As they age, children's reasoning about testimony increasingly reflects an ability not just to detect imperfect or inaccurate claims but also to assess what inferences may or may not be drawn about informants given their particular situation. Children also attend to the broader characteristics of particular informants-their group membership, personality characteristics, and agreement or disagreement with other potential informants. When presented with unexpected or counterintuitive testimony, children are prone to set aside their own prior convictions, but they may sometimes defer to informants for inherently social reasons.

Infants' acceptance of phonotactically illegal word forms as object labels

We investigated 16- and 20-month-olds' flexibility in mapping phonotactically illegal words to objects. Using an associative word-learning task, infants were presented with a training phase that either highlighted or did not highlight the referential status of a novel label. Infants were then habituated to two novel objects, each paired with a phonotactically illegal Czech word. When referential cues were provided, 16-, but not 20-month-olds, formed word-object mappings. In the absence of referential cues, infants of both ages failed to map the novel words. These findings illustrate the complex interplay between infants' developing sound system and their word learning abilities.

Reasoning about knowledge: Children's evaluations of generality and verifiability

In a series of experiments, we examined 3- to 8-year-old children's (N=223) and adults' (N=32) use of two properties of testimony to estimate a speaker's knowledge: generality and verifiability. Participants were presented with a "Generic speaker" who made a series of 4 general claims about "pangolins" (a novel animal kind), and a "Specific speaker" who made a series of 4 specific claims about "this pangolin" as an individual. To investigate the role of verifiability, we systematically varied whether the claim referred to a perceptually-obvious feature visible in a picture (e.g., "has a pointy nose") or a non-evident feature that was not visible (e.g., "sleeps in a hollow tree"). Three main findings emerged: (1) young children showed a pronounced reliance on verifiability that decreased with age. Three-year-old children were especially prone to credit knowledge to speakers who made verifiable claims, whereas 7- to 8-year-olds and adults credited knowledge to generic speakers regardless of whether the claims were verifiable; (2) children's attributions of knowledge to generic speakers was not detectable until age 5, and only when those claims were also verifiable; (3) children often generalized speakers' knowledge outside of the pangolin domain, indicating a belief that a person's knowledge about pangolins likely extends to new facts. Findings indicate that young children may be inclined to doubt speakers who make claims they cannot verify themselves, as well as a developmentally increasing appreciation for speakers who make general claims.