Remembering kinds: new evidence that categories are privileged in children's thinking

Children's developing ability to recognize deceptive use of true information

The strategic use of deliberate omissions, conveying true but selective information for deceptive purposes, is a prevalent and pernicious disinformation tactic. Crucially, its recognition requires engaging in a sophisticated, multi-part social cognitive reasoning process. In two preregistered studies, we investigated the development of children's ability to engage in this process and successfully recognize this form of deception, finding that children even as young as 5 years are capable of doing so, but only with sufficient scaffolding. This work highlights the key role that social cognition plays in the ability to recognize the manipulation techniques that underpin disinformation. It suggests that the interrelated development of pragmatic competence and epistemic vigilance can be harnessed in the design of tools and strategies to help bolster psychological resistance against disinformation in even our youngest citizens-children at the outset of formal education.

Parents' talk about conceptual categories with infants: stability, variability, and implications for expressive language development

Children's exposure to talk about conceptual categories plays a powerful role in shaping their conceptual development. However, it remains unclear when parents begin to talk about categories with young children and whether such talk relates to children's language skills. This study examines relations between parents' talk about conceptual categories and infants' expressive language development. Forty-seven parent-infant dyads were videotaped playing together at child age 10, 12, 14, and 16 months. Transcripts of interactions were analyzed to identify parents' talk about conceptual categories. Children's expressive language development was assessed at 18 months. Findings indicate that parents indeed talked about conceptual categories with infants and that talk was stable across time, with college-educated parents producing more than non-college-educated parents. Further, parents' talk about conceptual categories between 10 and 16 months predicted children's 18-month expressive language. This study sheds new light on mechanisms through which early experiences may support children's language development.

The influence of language input on 3-year-olds' learning about novel social categories

There is considerable variability in the social categories that children essentialize and the types of expectations children form about these categories, suggesting children's essentialist beliefs are shaped by environmental input. Prior studies have shown that exposure to generic statements about a social category promotes essentialist beliefs in 4.5- to 8-year-old children. However, by this age children form essentialist beliefs quite robustly, and thus it is unclear whether generic statements impact children's expectations about social categories at younger ages when essentialist beliefs first begin to emerge. Moreover, in prior studies the generic statements were delivered by an experimenter and carefully controlled, and thus it is unclear whether these statements would have the same impact if they occurred in a somewhat less constrained setting, such as parents reading a picture book to their child. The current study addressed these open questions by investigating whether generic statements delivered during a picture-book interaction with their parents influenced 3-year-olds' expectations about members of a novel social category. Our results showed that children who heard generic statements during the picture-book interaction used social-group membership to make inferences about the likely behavior of a novel category member, whereas children who were not exposed to generic statements did not. These findings suggest that as early as 3 years of age, children's expectations about social categories are influenced by generic statements that occur during brief parent-child interactions.

Preschoolers' ingroup bias in predicting others' sharing: The role of contexts and theory of mind

The current study investigated preschoolers' ingroup bias in predicting people's sharing across contexts and its relation to second-order theory of mind (ToM) ability. In Experiment 1, 96 5- and 6-year-old children were assigned to one of two groups in a minimal group paradigm. They heard a story about fictional ingroup and outgroup peers sharing in a public or private condition and were asked to predict and evaluate their sharing behavior. Children predicted that ingroup peers would share more than outgroup peers and also showed ingroup bias in evaluation regardless of the equal actual sharing of ingroup and outgroup peers. Moreover, 6-year-olds displayed a flexible ingroup bias in predicting others' sharing across conditions because they held such a bias only in public conditions and did not expect ingroup and outgroup peers to share differently in private conditions. Experiment 2 tested a new sample of 80 6-year-olds with the same sharing story and a second-order false belief task. Results showed that only 6-year-olds who fully passed the false belief task showed a flexible bias in predicting sharing across conditions. Results indicate that children's ingroup bias in predicting others' sharing is becoming flexible across contexts as they grow up and ToM skills contribute to the development of their increasingly sophisticated prosocial reasoning.

The Unintended Consequences of the Things We Say: What Generic Statements Communicate to Children About Unmentioned Categories

Adults frequently use generic language (e.g., "Boys play sports") to communicate information about social groups to children. Whereas previous research speaks to how children often interpret information about the groups described by generic statements, less is known about what generic claims may implicitly communicate about unmentioned groups (e.g., the possibility that "Boys play sports" implies that girls do not). Study 1 (287 four- to six-year-olds, 56 adults) and Study 2 (84 four- to six-year-olds) found that children as young as 4.5 years draw inferences about unmentioned categories from generic claims (but not matched specific statements)-and that the tendency to make these inferences strengthens with age. Study 3 (181 four- to seven-year-olds, 65 adults) provides evidence that pragmatic reasoning serves as a mechanism underlying these inferences. We conclude by discussing the role that generic language may play in inadvertently communicating social stereotypes to young children.

Are category labels primary? Children use similarities to reason about social groups

While interpersonal similarities impact young children's peer judgments, little work has assessed whether they also guide group-based reasoning. A common assumption has been that category labels rather than 'mere' similarities are unique constituents of such reasoning; the present work challenges this. Children (ages 3-9) viewed groups defined by category labels or shared preferences, and their social inferences were assessed. By age 5, children used both types of information to licence predictions about preferences (Study 1, n = 129) and richer forms of coalitional structure (Study 2, n = 205). Low-level explanations could not account for this pattern (Study 3, n = 72). Finally, older but not younger children privileged labelled categories when they were pitted against similarity (Study 4, n = 51). These studies show that young children use shared preferences to reason about relationships and coalitional structure, suggesting that similarities are central to the emergence of group representations.

A formal model of fuzzy-trace theory: Variations on framing effects and the Allais paradox

Fuzzy-trace theory assumes that decision-makers process qualitative "gist" representations and quantitative "verbatim" representations in parallel. We develop a lattice model of fuzzy-trace theory that explains both processes. Specifically, the model provides a novel formalization of how: 1) decision-makers encode multiple representations of options in parallel; 2) representations compete or combine so that choices often turn on the simplest representation of encoded gists; and 3) choices between representations are made based on positive vs. negative valences associated with social and moral principles stored in long-term memory (e.g., saving lives is good). The model integrates effects of individual differences in numeracy, metacognitive monitoring and editing, and sensation seeking. We conducted a systematic review of variations on framing effects and the Allais Paradox, both core phenomena of risky decision-making, and tested whether our model could predict observed choices: The model successfully predicted 82 out of 88 (93%) pairs of studies (comparing gain to loss conditions) demonstrating 16 variations on effects, theoretically critical manipulations that eliminate or exaggerate framing effects. When examining these conditions individually, the model successfully predicted 153 (90%) out of 170 eligible studies. Parameters of the model varied in theoretically meaningful ways with differences in numeracy, metacognitive monitoring, and sensation seeking, accounting for risk preferences at the group level. New experiments show similar results at the individual level. The model is also shown to be scientifically parsimonious using standard measures. Relations to current theories, such as Cumulative Prospect Theory, and potential extensions are discussed.

Group presence, category labels, and generic statements influence children to treat descriptive group regularities as prescriptive

Children use descriptive regularities of social groups (what is) to generate prescriptive judgments (what should be). We examined whether this tendency held when the regularities were introduced through group presence, category labels, or generic statements. Children (ages 4-9years, N=203) were randomly assigned to one of four conditions that manipulated how descriptive group regularities were presented: group presence (e.g., "These ones [a group of three individuals] eat this kind of berry"), category labels (e.g., "This [individual] Hibble eats this kind of berry"), generic statements (e.g., [showing an individual] "Hibbles eat this kind of berry"), or control (e.g., "This one [individual] eats this kind of berry"). Then, children saw conforming and non-conforming individuals and were asked to evaluate their behavior. As predicted, children evaluated non-conformity negatively in all conditions except the control condition. Together, these results suggest that minimal perceptual and linguistic cues provoke children to treat social groups as having normative force.

So It Is, So It Shall Be: Group Regularities License Children's Prescriptive Judgments

When do descriptive regularities (what characteristics individuals have) become prescriptive norms (what characteristics individuals should have)? We examined children's (4-13 years) and adults' use of group regularities to make prescriptive judgments, employing novel groups (Hibbles and Glerks) that engaged in morally neutral behaviors (e.g., eating different kinds of berries). Participants were introduced to conforming or non-conforming individuals (e.g., a Hibble who ate berries more typical of a Glerk). Children negatively evaluated non-conformity, with negative evaluations declining with age (Study 1). These effects were replicable across competitive and cooperative intergroup contexts (Study 2) and stemmed from reasoning about group regularities rather than reasoning about individual regularities (Study 3). These data provide new insights into children's group concepts and have important implications for understanding the development of stereotyping and norm enforcement.

Memory for generic and quantified sentences in Spanish-speaking children and adults

Generic language ( Owls eat at night) expresses knowledge about categories and may represent a cognitively default mode of generalization. English-speaking children and adults more accurately recall generic than quantified sentences ( All owls eat at night) and tend to recall quantified sentences as generic. However, generics in English are shorter than quantified sentences, and may be better recalled for this reason. The present study provided a new test of the issue in Spanish, where generics are expressed with an additional linguistic element not found in certain quantified sentences ( Los búhos comen de noche 'Owls eat at night' [generic] vs. Muchos búhos comen de noche 'Many owls eat at night' [quantified]). Both preschoolers and adults recalled generics more accurately than quantified sentences, and quantified sentences were more often recalled as generic than the reverse. These findings provide strong additional evidence for generics as a cognitive default, in an understudied cultural context.

Generics license 30-month-olds' inferences about the atypical properties of novel kinds

We examined whether the distinction between generic and nongeneric language provides toddlers with a rapid and efficient means to learn about kinds. In Experiment 1, we examined 30-month-olds' willingness to extend atypical properties to members of an unfamiliar category when the properties were introduced in 1 of 3 ways: (a) using a generic noun phrase ("Blicks drink ketchup"); (b) using a nongeneric noun phrase ("These blicks drink ketchup"); and (c) using an attentional phrase ("Look at this"). Hearing a generic noun phrase boosted toddlers' extension of properties to both the model exemplars and to novel members of the same category, relative to when a property had been introduced with a nongeneric noun phrase or an attentional phrase. In Experiment 2, properties were introduced with a generic noun phrase, and toddlers extended novel properties to members of the same-category, but not to an out-of-category object. Taken together, these findings demonstrate that generics highlight the stability of a feature and foster generalization of the property to novel within-category exemplars. (PsycINFO Database Record

How do generic statements impact performance? Evidence for entity beliefs

Generic statements about the abilities of children's social groups (e.g. 'Girls/Boys are good at this game') negatively impact children's performance - even if the statements are favorable towards children's own social groups. We explored the mechanism by which generic language impairs children's performance. Across three studies, our findings suggest that generic statements influence children's performance by creating an entity belief (i.e. a belief that a fixed ability determines performance). Children who were exposed to a generic statement about their social group's ability performed worse than children in control conditions. This effect hurt children's performance even when the person who made the generic statement was no longer present and a new person not privy to the statement replaced them. However, when children heard a generic statement paired with an effort explanation (i.e. 'Girls/Boys are good at this game because they try really hard when they draw') they performed better than children who heard the generic statement with no explanation (i.e. just 'Girls/Boys are good at this game') and children who heard the generic statement paired with a trait explanation (i.e. 'Girls/Boys are good at this game because they are smart and really good at drawing'). This work uncovers when and how generic statements that refer to the ability of one's social group hinder performance, informing the development of practices to improve student motivation and learning.

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.

Leave Her out of It: Person-Presentation of Strategies is Harmful for Transfer

A common practice in textbooks is to introduce concepts or strategies in association with specific people. This practice aligns with research suggesting that using "real-world" contexts in textbooks increases students' motivation and engagement. However, other research suggests this practice may interfere with transfer by distracting students or leading them to tie new knowledge too closely to the original learning context. The current study investigates the effects on learning and transfer of connecting mathematics strategies to specific people. A total of 180 college students were presented with an example of a problem-solving strategy that was either linked with a specific person (e.g., "Juan's strategy") or presented without a person. Students who saw the example without a person were more likely to correctly transfer the novel strategy to new problems than students who saw the example presented with a person. These findings are the first evidence that using people to present new strategies is harmful for learning and transfer.

Using the reassignment procedure to test object representation in pigeons and people

In four experiments, we evaluated Lea's (1984) reassignment procedure for studying object representation in pigeons (Experiments 1-3) and humans (Experiment 4). In the initial phase of Experiment 1, pigeons were taught to make discriminative button responses to five views of each of four objects. Using the same set of buttons in the second phase, one view of each object was trained to a different button. In the final phase, the four views that had been withheld in the second stage were shown. In Experiment 2, pigeons were initially trained just like the birds in Experiment 1. Then, one view of each object was reassigned to a different button, now using a new set of four response buttons. In Experiment 3, the reassignment paradigm was again tested using the number of pecks to bind together different views of the same object. Across all three experiments, pigeons showed statistically significant generalization of the new response to the non-reassigned views, but such responding was well below that to the reassigned view. In Experiment 4, human participants were studied using the same stimuli and task as the pigeons in Experiment 1. People did strongly generalize the new response to the non-reassigned views. These results indicate that humans, but not pigeons, can employ a unified object representation that they can flexibly map to different responses under the reassignment procedure.

Children's Recall of Generic and Specific Labels Regarding Animals and People

Although children tend to categorize objects at the basic level, we hypothesized that generic sentences would direct children's attention to different levels of categorization. We tested children's and adults' short-term recall (Study 1) and longer-term recall (Study 2) for labels presented in generic sentences (e.g., Kids like to play jimjam) versus specific sentences (e.g., This kid likes to play jimjam). Label content was either basic level (e.g., cat, boy) or superordinate (e.g., animal, kid). As predicted, participants showed better memory for label content in generic than specific sentences (short-term recall for children; both short and longer-term recall for adults). Errors typically involved recalling specific noun phrases as generic, and recalling superordinate labels as basic. These results demonstrate that language influences children's representations of new factual information, but that cognitive biases also lead to distortions in recall.

Memory errors reveal a bias to spontaneously generalize to categories

Much evidence suggests that, from a young age, humans are able to generalize information learned about a subset of a category to the category itself. Here, we propose that-beyond simply being able to perform such generalizations-people are biased to generalize to categories, such that they routinely make spontaneous, implicit category generalizations from information that licenses such generalizations. To demonstrate the existence of this bias, we asked participants to perform a task in which category generalizations would distract from the main goal of the task, leading to a characteristic pattern of errors. Specifically, participants were asked to memorize two types of novel facts: quantified facts about sets of kind members (e.g., facts about all or many stups) and generic facts about entire kinds (e.g., facts about zorbs as a kind). Moreover, half of the facts concerned properties that are typically generalizable to an animal kind (e.g., eating fruits and vegetables), and half concerned properties that are typically more idiosyncratic (e.g., getting mud in their hair). We predicted that-because of the hypothesized bias-participants would spontaneously generalize the quantified facts to the corresponding kinds, and would do so more frequently for the facts about generalizable (rather than idiosyncratic) properties. In turn, these generalizations would lead to a higher rate of quantified-to-generic memory errors for the generalizable properties. The results of four experiments (N = 449) supported this prediction. Moreover, the same generalizable-versus-idiosyncratic difference in memory errors occurred even under cognitive load, which suggests that the hypothesized bias operates unnoticed in the background, requiring few cognitive resources. In sum, this evidence suggests the presence of a powerful bias to draw generalizations about kinds.

Building theory-based concepts: four-year-olds preferentially seek explanations for features of kinds

Is the structure of human concepts continuous across development, or does it undergo qualitative transformations? Extensive evidence with adults has demonstrated that they are motivated to understand why categories have the features they do. To investigate whether young children display a similar motivation-an issue that bears on the question of continuity vs. transformation in conceptual structure-we conducted three studies involving 4-year-olds (N=90) and adults (N=124). Experiments 1 and 2 suggested that 4-year-olds indeed display a strong motivation to explain why categories have the features they do. Specifically, when provided with the option of asking "why?" about features of novel categories vs. features of individuals from other novel categories, children preferred to ask "why?" about the category features. Moreover, children's explanatory preference was specific to facts about categories per se and did not extend to facts that were merely presented in the context of multiple category instances. Experiment 3 also ruled out the possibility that the category facts were preferred because these facts were more surprising. In sum, these three studies reveal an early-emerging motivation to make sense of the categories encountered in the world and, more generally, speak to the richness of children's conceptual representations.

Property content guides children's memory for social learning episodes

How do children's interpretations of the generality of learning episodes affect what they encode? In the present studies, we investigated the hypothesis that children encode distinct aspects of learning episodes containing generalizable and non-generalizable properties. Two studies with preschool (N=50) and young school-aged children (N=49) reveal that their encoding is contingent on the generalizability of the property they are learning. Children remembered generalizable properties (e.g., morphological or normative properties) more than non-generalizable properties (e.g., historical events or preferences). Conversely, they remembered category exemplars associated with non-generalizable properties more than category exemplars associated with generalizable properties. The findings highlight the utility of remembering distinct aspects of social learning episodes for children's future generalization.

When children ignore evidence in category-based induction. Irrational inferences?

The process of induction--generalizing information obtained from limited samples to inform broader understandings--plays a critical role in learning across the life span. Previous research on the development of induction has found important developmental changes in one critical component of induction--how children and adults evaluate whether a sample of evidence is informative about a broader category. In particular, when acquiring knowledge about biological kinds, adults view samples that provide diverse representation of a category (e.g. an eagle, a penguin, and a robin, for the category birds) as more informative than a less diverse sample (e.g. three robins) for drawing inferences about the kind. In contrast, children younger than 8 years often neglect this feature of sample composition, viewing both types of samples as equivalently informative. Is this a case of children making irrational inferences? This chapter examines how these findings can be reconciled with rational constructivist approaches to cognitive development, focusing on (1) the role of the sampling context in determining how learners incorporate information about sample composition into inductive inferences and (2) how developmental differences in learners' intuitive theories influence how they make sense of new evidence. This chapter highlights how strong tests of rational approaches come from incidences where children's performance appears to be quite nonnormative.