Cross-classification and category representation in children's concepts

Development of food literacy in children and adolescents: implications for the design of strategies to promote healthier and more sustainable diets

Food literacy has emerged as a key individual trait to promote the transformation of food systems toward healthy and sustainable diets. Childhood and adolescence are key periods for establishing the foundations of eating habits. Different food literacy competencies are acquired as children develop different cognitive abilities, skills, and experiences, contributing to the development of critical tools that allow them to navigate a complex food system. Thus, the design and implementation of programs to support the development of food literacy from early childhood can contribute to healthier and more sustainable eating habits. In this context, the aim of the present narrative review is to provide an in-depth description of how different food literacy competencies are developed in childhood and adolescence, integrating the extensive body of evidence on cognitive, social, and food-related development. Implications for the development of multisectoral strategies to target the multidimensional nature of food literacy and promote the development of the 3 types of competencies (relational, functional, and critical) are discussed.

Does social-norm messaging influence expected satiety and ideal portion-size selection?

A person's perception of how long a food will stave off hunger (expected satiety) and the ideal amount to consume (ideal portion size) are both influenced by food-to-mealtime norms. Here, we examine whether social norms can modulate this effect, in three experimental studies. In study 1 (n = 235) participants were exposed to a social norm suggesting most people enjoyed consuming pasta for breakfast. There was a main effect of food-to-mealtime congruence for expected satiety and ideal portion size (p < 0.001) - participants selected a smaller portion of pasta for breakfast (vs. lunch) - but there were no other main effects/interactions (p ≥ 0.15). Study 2 (n = 200) followed the same approach as study 1, but sought to examine whether the typical volume of food consumed at breakfast and lunch needed to be controlled. Again, there was a main effect of congruence (the same pattern) (p ≤ 0.02) but no other main effects/interactions (p ≥ 0.73). Study 3 (n = 208) followed the same approach as study 2, but the social-norm message was changed to suggest that most people who eat pasta for breakfast found it effectively reduced their hunger. Again, there was a main effect of congruence (the same pattern) (p < 0.001) but no other main effects/interaction (p ≥ 0.26). These studies provide further evidence for the food-to-mealtime effect, but do not provide any evidence that a single, simple social-norm statement can modulate expected satiety or ideal portion size, or interact with the food-to-mealtime effect.

Holding multiple category representations: The role of age, theory of mind, and rule switching in children's developing cross-classification abilities

Cross-classification, the ability to categorize multifaceted entities in many ways, is a remarkable cognitive milestone for children. Past work has focused primarily on documenting the timeline for when children reach cross-classification competence. However, it is not well understood what cognitive factors underpin children's improvements. The current study aimed to examine the contributions of age, theory of mind, and rule switching to children's cross-classification development. We tested 3- to 5-year-old children (N = 75) using a cross-classification task, the Theory of Mind Task Battery, and the Three-Dimensional Change Card Sort test. The results revealed that age and theory of mind predict children's cross-classification over and above the effects of rule switching. The results also revealed that advanced-level theory of mind reasoning is a particularly strong predictor of cross-classification development. These findings increase understanding of cross-classification within children's broader cognitive development.

Sensitivity to Semantic Relationships in U.S. Monolingual English-Speaking Typical Talkers and Late Talkers

PURPOSE

Late talkers (LTs) are a group of children who exhibit delays in language development without a known cause. Although a hallmark of LTs is a reduced expressive vocabulary, little is known about LTs' processing of semantic relations among words in their emerging vocabularies. This study uses an eye-tracking task to compare 2-year-old LTs' and typical talkers' (TTs') sensitivity to semantic relationships among early acquired words.

METHOD

U.S. monolingual English-speaking LTs (n = 21) and TTs (n = 24) completed a looking-while-listening task in which they viewed two images on a screen (e.g., a shirt and a pizza), while they heard words that referred to one of the images (e.g., Look! Shirt!; target-present condition) or a semantically related item (e.g., Look! Hat!; target-absent condition). Children's eye movements (i.e., looks to the target) were monitored to assess their sensitivity to these semantic relationships.

RESULTS

Both LTs and TTs looked longer at the semantically related image than the unrelated image on target-absent trials, demonstrating sensitivity to the taxonomic relationships used in the experiment. There was no significant group difference between LTs and TTs. Both groups also looked more to the target in the target-present condition than in the target-absent condition.

CONCLUSIONS

These results reveal that, despite possessing smaller expressive vocabularies, LTs have encoded semantic relationships in their receptive vocabularies and activate these during real-time language comprehension. This study furthers our understanding of LTs' emerging linguistic systems and language processing skills.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23303987.

Offering vegetables to children at breakfast time in nursery and kindergarten settings: the Veggie Brek feasibility and acceptability cluster randomised controlled trial

BACKGROUND

In many Westernised countries, children do not consume a sufficient amount of vegetables for optimal health and development. Child-feeding guidelines have been produced to address this, but often only promote offering vegetables at midday/evening meals and snack times. With guidance having limited success in increasing children's vegetable intake at a population level, novel approaches to address this must be developed. Offering vegetables to children at breakfast time in nursery/kindergarten settings has the potential to increase children's overall daily vegetable consumption as children typically attend nursery/kindergarten and many routinely eat breakfast there. However, the feasibility and acceptability of this intervention (Veggie Brek) to children and nursery staff has not been investigated.

METHODS

A feasibility and acceptability cluster randomised controlled trial (RCT) was undertaken in eight UK nurseries. All nurseries engaged in one-week baseline and follow-up phases before and after an intervention/control period. Staff in intervention nurseries offered three raw carrot batons and three cucumber sticks alongside children's main breakfast food each day for three weeks. Control nurseries offered children their usual breakfast. Feasibility was assessed by recruitment data and nursery staff's ability to follow the trial protocol. Acceptability was assessed by children's willingness to eat the vegetables at breakfast time. All primary outcomes were assessed against traffic-light progression criteria. Staff preference for collecting data via photographs versus using paper was also assessed. Further views about the intervention were obtained through semi-structured interviews with nursery staff.

RESULTS

The recruitment of parents/caregivers willing to provide consent for eligible children was acceptable at 67.8% (within the amber stop-go criterion) with 351 children taking part across eight nurseries. Both the feasibility and acceptability of the intervention to nursery staff and the willingness of children to consume the vegetables met the green stop-go criteria, with children eating some part of the vegetables in 62.4% (745/1194) of instances where vegetables were offered. Additionally, staff preferred reporting data using paper compared to taking photographs.

CONCLUSIONS

Offering vegetables to children at breakfast time in nursery/kindergarten settings is feasible and acceptable to children and nursery staff. A full intervention evaluation should be explored via a definitive RCT.

TRIAL REGISTRATION

NCT05217550.

Would offering vegetables to children for breakfast increase their total daily vegetable intake?

The consumption of vegetables is vitally important for children's health and development. However, in many Westernised countries, most children do not eat sufficient quantities of vegetables and consume many energy-dense and high-sugar foods; a health behaviour associated with the onset of non-communicable diseases. To address this important public health concern, it is necessary to think 'outside the box' and consider innovative and pragmatic ways to increase children's daily vegetable intake. In many countries, caregivers implementing best-practice child feeding methods typically offer children vegetables at lunch, dinner and for snacks. It is unusual for children to be routinely offered vegetables for breakfast, yet there is no nutritional, physiological or medical reason why vegetables should not be eaten at breakfast. Indeed, in some countries, children frequently consume vegetables for breakfast. Increasing children's exposure to vegetables at breakfast from an early age would allow for the development of a positive association between eating vegetables and breakfast, thus providing another opportunity in the day where vegetables might be regularly consumed by children. In this paper, we propose a rationale for why vegetables should be routinely offered to young children at breakfast time in countries where this may not be the norm. Future research assessing the feasibility and acceptability of such a public health intervention would provide health policy agencies with evidence about a potentially effective and easily implementable approach for increasing children's vegetable intake, thus improving their overall nutritional status, as well as their heath and development.

Cognitive-Based Interventions Break Gender Stereotypes in Kindergarten Children

Despite the growing recognition of gender equality worldwide, plausible strategies that reduce young children's gender stereotypes remain limited. Cognitive-based interventions have been widely used in school settings and have been suggested to play important roles in children's gender stereotyping and in their processing of counter-stereotypic information. We aimed to determine whether exposure to counter-stereotypical information could break gender stereotypes in kindergarten children. Fifty-four children (61-79 months old) from two public kindergarten classes in northern Taiwan participated in this study. One of the two classes was randomly selected as the experimental group (n = 28), and the other was the control group (n = 26). The experimental group consisted of a gender equality curriculum including script relationship training for two months, while the control group continued their regular curriculum. The picture classification task (PCT) was measured before and after the intervention to assess gender stereotypes. Before interventions, 87.50% of the children chose a gender stereotypic relationship, while 12.50% chose script/other relationships in PCT. After the interventions, the gender stereotypic relationship dropped to 73.22% in the experimental group. Children in the control group were more likely to maintain their gender stereotypic relationship choices in PCTs. Our findings suggest that cognitive-based interventions, such as a gender equality curriculum, have the potential to break gender stereotypes in kindergarten children.

Young Children's Food-Related Knowledge: Kindergartners' Free Categorization of Food Items

OBJECTIVE

Studies concerning young children's food-related knowledge have dealt mostly with specific types of knowledge or with researchers' predetermined categories. This approach may neglect certain aspects of children's knowledge and may limit the understanding of its general structure. The present study aimed to examine and analyze a wide scope of young children's constructed food-related knowledge.

METHODS

Qualitative thematic analysis of 40 kindergartners' free categorizations of food items.

RESULTS

Children's food-related knowledge was broad and derived from 3 primary sources: personal experience, environmental experience, and perceived messages. Novel aspects of knowledge were found, such as different treatments of food and partial familiarity with nutrients.

CONCLUSIONS AND IMPLICATIONS

The findings demonstrated the existence of various types of young children's food-related knowledge. Attention to the broad spectrum of their knowledge and its possible sources may contribute to the design of relevant and effective nutrition education interventions aimed at young children.

The Emergence of Richly Organized Semantic Knowledge from Simple Statistics: A Synthetic Review

As adults, we draw upon our ample knowledge about the world to support such vital cognitive feats as using language, reasoning, retrieving knowledge relevant to our current goals, planning for the future, adapting to unexpected events, and navigating through the environment. Our knowledge readily supports these feats because it is not merely a collection of stored facts, but rather functions as an organized, semantic network of concepts connected by meaningful relations. How do the relations that fundamentally organize semantic concepts emerge with development? Here, we cast a spotlight on a potentially powerful but often overlooked driver of semantic organization: Rich statistical regularities that are ubiquitous in both language and visual input. In this synthetic review, we show that a driving role for statistical regularities is convergently supported by evidence from diverse fields, including computational modeling, statistical learning, and semantic development. Finally, we identify a number of key avenues of future research into how statistical regularities may drive the development of semantic organization.

Development of Conceptual Flexibility in Intuitive Biology: Effects of Environment and Experience

Living things can be classified in many ways, such as taxonomic similarity (lions and lynx), or shared ecological habitat (ducks and turtles). The present studies used card-sorting and triad tasks to explore developmental and experiential changes in conceptual flexibility-the ability to switch between taxonomic and ecological construals of living things-as well as two processes underlying conceptual flexibility: salience (i.e., the ease with which relations come to mind outside of contextual influences) and availability (i.e., the presence of relations in one's mental space) of taxonomic and ecological relations. We were also interested in the extent to which salience and availability of taxonomic and ecological relations predicted inductive inferences. Participants were 452 six to ten-year-olds from urban, suburban, and rural communities in New England. Across two studies, taxonomic relations were overwhelmingly more salient than ecological relations, although salience of ecological relations was higher among children from rural environments (Study 1) and those who engaged in unstructured exploration of nature (Study 2). Availability of ecological relations, as well as conceptual flexibility, increased with age, and was higher among children living in more rural environments. Notably, salience, but not availability, of ecological relations predicted ecological inferences. These findings suggest that taxonomic categories (i.e., groups that share both perceptual similarities and rich underlying structure) are a salient way to organize intuitive biological knowledge and that, critically, environmental richness and relevant experience contribute to the salience and availability of ecological knowledge, and thereby, conceptual flexibility in biological thinking. More generally, they highlight important linkages between domain-specific knowledge and domain-general cognitive abilities.

The Role of Co-Occurrence Statistics in Developing Semantic Knowledge

The organization of our knowledge about the world into an interconnected network of concepts linked by relations profoundly impacts many facets of cognition, including attention, memory retrieval, reasoning, and learning. It is therefore crucial to understand how organized semantic representations are acquired. The present experiment investigated the contributions of readily observable environmental statistical regularities to semantic organization in childhood. Specifically, we investigated whether co-occurrence regularities with which entities or their labels more reliably occur together than with others (a) contribute to relations between concepts independently and (b) contribute to relations between concepts belonging to the same taxonomic category. Using child-directed speech corpora to estimate reliable co-occurrences between labels for familiar items, we constructed triads consisting of a target, a related distractor, and an unrelated distractor in which targets and related distractors consistently co-occurred (e.g., sock-foot), belonged to the same taxonomic category (e.g., sock-coat), or both (e.g., sock-shoe). We used an implicit, eye-gaze measure of relations between concepts based on the degree to which children (N = 72, age 4-7 years) looked at related versus unrelated distractors when asked to look for a target. The results indicated that co-occurrence both independently contributes to relations between concepts and contributes to relations between concepts belonging to the same taxonomic category. These findings suggest that sensitivity to the regularity with which different entities co-occur in children's environments shapes the organization of semantic knowledge during development. Implications for theoretical accounts and empirical investigations of semantic organization are discussed.

Lumping and splitting: Developmental changes in the structure of children's semantic networks

Organized semantic representations encoding across- and within-domain distinctions are a hallmark of mature cognition, and understanding how they change with experience and learning is a key endeavor in developmental science. Existing computational modeling studies provide a mechanistic framework for understanding how structured semantic representations emerge as a result of development and learning. However, their predictions remain largely untested in young children, with the existing evidence providing only indirect tests of these predictions. Across two experiments, we provide the first direct examination of a key prediction derived from these computational models-that early in development, broad across-domain distinctions should generally be more strongly represented relative to finer-grained within-domain distinctions. The results support this hypothesis, being consistent with the exploitation of patterns of covariation among entities as a mechanism supporting the acquisition of structured semantic representations.

Sensitivity detection in memory recognition: interference control as index of taxonomic memory development?

We investigated how long-term memory modulates recognition accuracy performance in typically developing primary school children (aged 7 vs. 9 years). We devised a verbal working memory task where words associations were manipulated to obtain different types of semantic associations (i.e., taxonomic, thematic). Sensitivity detection measures were operationalised as difference between hits and false alarms (for both internal and external intrusions). As our main result, we found sensitivity detection for taxonomic associations was greater in older children than younger. In turn, this showed that taxonomies produce more interference in younger children, and thus, they are not able to take advantage from taxonomic associations, as older children do. These results are helpful in sketching a developmental trend of how semantic memory impacts recognition processes in memory.

[Formula: see text] Developmental dyslexia: How taxonomic and thematic organization affect working memory recall

Semantic long-term memory (LTM) representations can be distinguished in two main classes: taxonomic (i.e., abstract) and thematic (i.e., concrete, experiential). In typically developing children, taxonomies are usually acquired after thematic representations. In the current study, we investigated how LTM semantic representations modulate working memory (WM) recall in children with developmental dyslexia (DD). A sample of children with DD from primary and secondary school paired with a control group for age, gender, schooling, and IQ was administered a semantic WM (SWM) dual task. Here, children had to listen to groups of lists composed of words semantically related (taxonomic, e.g., shop- drugstore-coffee; or thematic, e.g., light-heat-fire) or arbitrarily related, and afterward to recall the last words among each group. Both taxonomic and thematic organizations supported recall in the two groups of children. More specifically, data showed that in typically developing children the taxonomic organization boosted WM recall (vs. the thematic one). On the contrary, in children with DD, the taxonomic organization did not better support recall and yielded effects similar to thematic organization. In children with DD, abstract taxonomic knowledge seems to be less frequently used than thematic knowledge. Findings contribute to sketch memory functioning across different memory systems in DD.

Rapid, experience-related changes in the organization of children's semantic knowledge

The organization of knowledge according to relations between concepts is crucially important for many cognitive processes, and its emergence during childhood is a key focus of cognitive development research. Prior evidence about the role of learning and experience in the development of knowledge organization primarily comes from studies investigating differences between preexisting, naturally occurring groups (e.g., children from rural vs. urban settings, children who own a pet vs. children who do not) and a handful of studies on the effects of researcher-developed educational interventions. However, we know little about whether knowledge organization can be relatively rapidly molded by shorter-term real-world learning experiences (e.g., on a timescale of days vs. years or months). The current study investigated whether naturalistic learning experiences can drive rapid measurable changes in knowledge organization in children by investigating the effects of a week-long zoo summer camp (compared with a control school-based camp) on the degree to which 4- to 9-year-old children's knowledge about animals was organized according to taxonomic relations. Although there were no differences in taxonomic organization between the zoo camp and the school-based camp at pretest, only children who participated in the zoo camp showed increases in taxonomic organization at posttest. Moreover, analyses of changes in taxonomic organization in zoo camp children suggested that these changes were primarily driven by improvements in the degree to which children differentiated between taxonomic categories. These findings provide novel evidence that naturalistic experiences can drive rapid changes in knowledge organization.

Peas, please! Food familiarization through picture books helps parents introduce vegetables into preschoolers' diets

Repeated taste exposure is an established means of increasing children's liking and intake of fruit and vegetables. However, parents find it difficult to offer children disliked foods repeatedly, often giving up after a few attempts. Studies show that familiarizing children to fruit and vegetables through picture books can increase their interest in tasting targeted foods. This study explored whether looking at picture books before providing foods to taste improved the outcomes of a home-delivered taste exposure regime. Parents of 127 toddlers (aged 21-24 months) identified two 'target' foods they wanted their child to eat (1 fruit, 1 vegetable). Families were randomly assigned to one of three groups. Parents and children in two experimental groups looked at books about either the target fruit or vegetable every day for two weeks; the control group did not receive a book. Parents in all three groups were then asked to offer their child both target foods every day during a 2-week taste-exposure phase. Parental ratings of children's liking and consumption of the foods were collected at baseline, immediately following taste-exposure (post-intervention), and 3 months later (follow-up). In all groups, liking of both foods increased following taste exposure and remained above baseline at follow-up (all ps < .001). In addition, compared to the control group who experienced only taste exposure, looking at vegetable books enhanced children's liking of their target vegetable post-intervention (p < .001) and at follow-up (p < .05), and increased consumption of the vegetable at follow-up (p < .01). Exposure to vegetable books was also associated with smaller increases in neophobia and food fussiness over the period of the study compared to controls (ps < .01), suggesting that picture books may have positive, long-term impacts on children's attitudes towards new foods.

How Infants and Young Children Learn About Food: A Systematic Review

Early childhood is a critical time for establishing food preferences and dietary habits. In order for appropriate advice to be available to parents and healthcare professionals it is essential for researchers to understand the ways in which children learn about foods. This review summarizes the literature relating to the role played by known developmental learning processes in the establishment of early eating behavior, food preferences and general knowledge about food, and identifies gaps in our knowledge that remain to be explored. A systematic literature search identified 48 papers exploring how young children learn about food from the start of complementary feeding to 36 months of age. The majority of the papers focus on evaluative components of children's learning about food, such as their food preferences, liking and acceptance. A smaller number of papers focus on other aspects of what and how children learn about food, such as a food's origins or appropriate eating contexts. The review identified papers relating to four developmental learning processes: (1) Familiarization to a food through repeated exposure to its taste, texture or appearance. This was found to be an effective technique for learning about foods, especially for children at the younger end of our age range. (2) Observational learning of food choice. Imitation of others' eating behavior was also found to play an important role in the first years of life. (3) Associative learning through flavor-nutrient and flavor-flavor learning (FFL). Although the subject of much investigation, conditioning techniques were not found to play a major role in shaping the food preferences of infants in the post-weaning and toddler periods. (4) Categorization of foods. The direct effects of the ability to categorize foods have been little studied in this age group. However, the literature suggests that what infants are willing to consume depends on their ability to recognize items on their plate as familiar exemplars of that food type.

Taxonomic and thematic semantic systems

Object concepts are critical for nearly all aspects of human cognition, from perception tasks like object recognition, to understanding and producing language, to making meaningful actions. Concepts can have 2 very different kinds of relations: similarity relations based on shared features (e.g., dog-bear), which are called "taxonomic" relations, and contiguity relations based on co-occurrence in events or scenarios (e.g., dog-leash), which are called "thematic" relations. Here, we report a systematic review of experimental psychology and cognitive neuroscience evidence of this distinction in the structure of semantic memory. We propose 2 principles that may drive the development of distinct taxonomic and thematic semantic systems: differences between which features determine taxonomic versus thematic relations, and differences in the processing required to extract taxonomic versus thematic relations. This review brings together distinct threads of behavioral, computational, and neuroscience research on semantic memory in support of a functional and neural dissociation, and defines a framework for future studies of semantic memory. (PsycINFO Database Record

Individual and developmental differences in preschoolers' categorization biases and vocabulary across tasks

This study bridges prior research on young children's use of taxonomic versus thematic relations to categorize objects with prior research on their use of shared shape versus shared function to categorize artifacts. Specifically, this research examined associations in children's categorization tendencies across these two dichotomies, including assessments of individual differences, developmental trends, and vocabulary level. Preschoolers (3- to 5-year-olds) completed a receptive vocabulary assessment and two match-to-sample tasks: one pitting (superordinate) taxonomic and thematic relations against each other and one pitting shape and function similarity against each other. The results revealed individual and developmental variation in children's cross-task categorization biases, with a predominant tendency to focus on both thematic and function relations that became increasingly stronger with age. In 3- and 5-year-olds, function-based categorization was also positively associated with verb vocabulary. These findings demonstrate an emerging tendency to focus on relational information during the preschool years that, among other learning effects, may benefit verb acquisition. The results are discussed in terms of the real-time processing and developmental factors that might contribute to the development of strategies for learning about objects and categories during early childhood.

The Semantic Associative Ability in Preschoolers with Different Language Onset Time

Aim of the study is to verify the semantic associative abilities in children with different language onset times: early, typical, and delayed talkers. The study was conducted on the sample of 74 preschool children who performed a Perceptual Associative Task, in order to evaluate the ability to link concepts by four associative strategies (function, part/whole, contiguity, and superordinate strategies). The results evidenced that the children with delayed language onset performed significantly better than the children with early language production. No difference was found between typical and delayed language groups. Our results showed that the children with early language onset presented weakness in the flexibility of elaboration of the concepts. The typical and delayed language onset groups overlapped performance in the associative abilities. The time of language onset appeared to be a predictive factor in the use of semantic associative strategies; the early talkers might present a slow pattern of conceptual processing, whereas the typical and late talkers may have protective factors.

Developmental changes in semantic knowledge organization

Semantic knowledge is a crucial aspect of higher cognition. Theoretical accounts of semantic knowledge posit that relations between concepts provide organizational structure that converts information known about individual entities into an interconnected network in which concepts can be linked by many types of relations (e.g., taxonomic, thematic). The goal of the current research was to address several methodological shortcomings of prior studies on the development of semantic organization, by using a variant of the spatial arrangement method (SpAM) to collect graded judgments of relatedness for a set of entities that can be cross-classified into either taxonomic or thematic groups. In Experiment 1, we used the cross-classify SpAM (CC-SpAM) to obtain graded relatedness judgments and derive a representation of developmental changes in the organization of semantic knowledge. In Experiment 2, we validated the findings of Experiment 1 by using a more traditional pairwise similarity judgment paradigm. Across both experiments, we found that an early recognition of links between entities that are both taxonomically and thematically related preceded an increasing recognition of links based on a single type of relation. The utility of CC-SpAM for evaluating theoretical accounts of semantic development is discussed.

Trust and doubt: An examination of children's decision to believe what they are told about food

The domain of food is one that is highly relevant and vital to the everyday lives of children. However, children's reasoning about this domain is poorly understood within the field of developmental psychology. Because children's learning about food, including its evaluative components (e.g., health, taste) is so heavily dependent on information conveyed by other people, a major developmental challenge that children face is determining who to distrust regarding food. In three studies, this investigation examined how 3- and 4-year-olds and adults (N=312) use different cues to determine when to ignore informant information (i.e., distrust what an informant tells them by choosing an alternative) in food- and non-food-specific scenarios. The results of Study 1 indicated that by age 4 years, children are less trusting of inaccurate sources of information compared with sources that have not demonstrated previous inaccuracy. Study 2 revealed that these results are applicable across the domain of objects. The results of Study 3 indicated that by age 4, children trust benevolent sources more often than malevolent ones. Thus, when reasoning about the evaluative components of food, by age 4, children appraise other people's untrustworthiness by paying attention to their inaccuracy and malevolence.

Inductive generalization with familiar categories: developmental changes in children's reliance on perceptual similarity and kind information

Inductive generalization is ubiquitous in human cognition; however, the factors underpinning this ability early in development remain contested. The present study was designed to (1) test the predictions of the naïve theory and a similarity-based account and (2) examine the mechanism by which labels promote induction. In Experiment 1, 3- to 5-year-old children made inferences about highly familiar categories. The results were not fully consistent with either theoretical account. In contrast to the predictions of the naïve theory approach, the youngest children in the study did not ignore perceptually compelling lures in favor of category-match items; in contrast to the predictions of the similarity-based account, no group of participants favored perceptually compelling lures in the presence of dissimilar-looking category-match items. In Experiment 2 we investigated the mechanisms by which labels promote induction by examining the influence of different label types, namely category labels (e.g., the target and category-match both labeled as bird) and descriptor labels (e.g., the target and the perceptual lure both labeled as brown) on induction performance. In contrast to the predictions of the naïve theory approach, descriptor labels but not category labels affected induction in 3-year-old children. Consistent with the predictions of the similarity-based account, descriptor labels affected the performance of children in all age groups included in the study. The implications of these findings for the developmental account of induction are discussed.

The contribution of language to the right-hemisphere conceptual representations: a selective survey

Although levels of verbal and pictorial performance are known to depend on the degree of left versus right atrophy in the early stages of semantic dementia, the nature of these differences remains controversial. It has been proposed that there is a unitary, bilaterally represented, abstract semantic system and that differential task performance reflects the impact of greater connectivity between the left anterior temporal lobe (ATL) and the left dominant language systems. This interpretation explains the greater involvement of the left ATL in verbally coded semantic knowledge, but not the prevalence of the right hemisphere in pictorial representations. An alternative account is provided by the sensory-motor model of conceptual knowledge, which assumes that each conceptual representation results from the convergence of different perceptual, motor, and verbally coded sources of knowledge in a given brain area. According to this model, the weight of verbal information should prevail in left ATL conceptual representations, because of the dominance of the left hemisphere for language, whereas the weight of sensory-motor sources of knowledge should be greater in the right ATL representations, because the right hemisphere plays a greater role in processing sensory-motor information. If the difference between right and left conceptual representations is quantitative and due to the different weight of sensory-motor and verbal sources of knowledge in their composition, we should observe an elementary, but selective representation of semantic-lexical knowledge in the intact right hemisphere and a mild but selective semantic-lexical impairment in right-brain-damaged patients. Results of the present survey support this hypothesis.

Redundancy matters: flexible learning of multiple contingencies in infants

Many objects and events can be categorized in different ways, and learning multiple categories in parallel often requires flexibly attending to different stimulus dimensions in different contexts. Although infants and young children often exhibit poor attentional control, several theoretical proposals argue that such flexibility can be achieved without selective attention. If this is the case, then even young infants should be able to learn multiple dimension-context contingencies in parallel. This possibility was tested in four experiments with 14- and 22-month-olds. Learning of contingencies succeeded as long as there were multiple correlations between the context and the to-be-learned dimension. These findings suggest that infants can learn multiple dimension-context contingencies in parallel, but only when there is sufficient redundancy in the input.

Generic language facilitates children's cross-classification

Four studies examined the role of generic language in facilitating 4- and 5-year-old children's ability to cross-classify. Participants were asked to classify an item into a familiar (taxonomic or script) category, then cross-classify it into a novel (script or taxonomic) category with the help of a clue expressed in either generic or specific language. Experiment 1 showed that generics facilitate 5-year-olds' and adults' cross-classification when expressed at an appropriate level of generalization (e.g., "foods," "birthday party things"), whereas Experiment 2 showed that such effects disappeared when labels were at an inappropriate level of generalization (e.g., "pizzas," "balloons"). Experiments 3 and 4 offered additional controls. Taken together, the findings demonstrate that language can guide and direct children's multiple categorizations.

Inductive selectivity in children's cross-classified concepts

Cross-classified items pose an interesting challenge to children's induction as these items belong to many different categories, each of which may serve as a basis for a different type of inference. Inductive selectivity is the ability to appropriately make different types of inferences about a single cross-classifiable item based on its different category memberships. This research includes 5 experiments that examine the development of inductive selectivity in 3-, 4-, and 5-year-olds (n=272). Overall, the results show that by age 4, children have inductive selectivity with taxonomic and script categories. That is, children use taxonomic categories to make biochemical inferences about an item whereas script categories to make situational inferences about an item.

The loss of conceptual associations in mild Alzheimer's dementia

Changes in semantic memory are a controversial topic in research on cognitive decline in aging. In this study, we analyzed whether the semantic deficits in mild Alzheimer's disease (AD) reflect the information acquisition process, and whether the deficits are related to when the information was initially stored. We hypothesized that in the earlier stages of dementia, the ability to access semantic associative relations reflects the use of these associations during different developmental stages. Specifically, we asserted that Alzheimer's patients might be able to access the relations that are learned earlier in life for the longest amount of time compared to those that are learned later. In this study, 254 subjects were divided into four groups (child, adult, senior, and Alzheimer's patients groups) and were evaluated with an experimental semantic association task that incorporated five semantic associative relations that were used to compare performance by age group. An analysis of variance (ANOVA) 4 × 5 test showed a significant main group effect, F(3, 250) = 97.1, p < .001, and an associative relations effect, F(4, 1000) = 23.1, p < .001, as well as an interaction of Group × Associative Relations, F(12, 1000) = 8.5, p < .001. The results demonstrated that the semantic associative relations that were acquired in later developmental stages were less preserved in persons with mild AD (i.e., superordinate relation, p < .0001). On the contrary, the semantic relations acquired earlier in childhood were better preserved in persons with mild AD. Our results suggest that semantic impairment begins with difficulties in using the associative relations that link concepts together in the semantic memory of patients with mild AD dementia (and possibly in individuals with mild cognitive impairment).

The role of external sources of information in children's evaluative food categories

Evaluative food categories are value-laden assessments which reflect the healthfulness and palatability of foods (e.g., healthy/unhealthy, yummy/yucky). In a series of three studies, this research examines how 3- to 4-year-old children (N = 147) form evaluative food categories based on input from external sources of information. The results indicate that children prefer to ask a mom and teacher over a cartoon and child for information about the evaluative status of foods. However, children are cautious to accept information about healthy foods from all of the external sources compared to unhealthy, yummy, and yucky foods. The results also indicate that providing information about the positive taste of healthy foods helps to encourage children to select healthy foods to eat. Taken together, these results have potential implications for children's health and nutrition education.

A theory-based approach to teaching young children about health: A recipe for understanding

The theory-theory account of conceptual development posits that children's concepts are integrated into theories. Concept learning studies have documented the central role that theories play in children's learning of experimenter-defined categories, but have yet to extensively examine complex, real-world concepts such as health. The present study examined whether providing young children with coherent and causally-related information in a theory-based lesson would facilitate their learning about the concept of health. This study used a pre-test/lesson/post-test design, plus a five month follow-up. Children were randomly assigned to one of three conditions: theory (i.e., 20 children received a theory-based lesson); nontheory (i.e., 20 children received a nontheory-based lesson); and control (i.e., 20 children received no lesson). Overall, the results showed that children in the theory condition had a more accurate conception of health than children in the nontheory and control conditions, suggesting the importance of theories in children's learning of complex, real-world concepts.

The semantic-similarity effect in children: influence of long-term knowledge on verbal short-term memory

The present research was designed to highlight the relation between children's categorical knowledge and their verbal short-term memory (STM) performance. To do this, we manipulated the categorical organization of the words composing lists to be memorized by 5- and 9-year-old children. Three types of word list were drawn up: semantically similar context-dependent (CD) lists, semantically similar context-independent (CI) lists, and semantically dissimilar lists. In line with the procedure used by Poirier and Saint-Aubin (1995), the dissimilar lists were produced using words from the semantically similar lists. Both 5- and 9-year-old children showed better recall for the semantically similar CD lists than they did for the unrelated lists. In the semantic similar CI condition, semantic similarity enhanced immediate serial recall only at age 9 but contributed to item information memory both at ages 5 and 9. These results, which indicate a semantic influence of long-term memory (LTM) on serial recall from age 5, are discussed in the light of current models of STM. Moreover, we suggest that differences between results at 5 and 9 years are compatible with pluralist models of development.

Becoming self-directed: abstract representations support endogenous flexibility in children

A fundamental part of growing up is going beyond routines. Children become increasingly skilled over the first years of life at actively maintaining goals in the service of flexible behavior, allowing them to break out of habits and switch from one task to another. Their early successes often occur with exogenous (externally-provided) goals, and only later with endogenous (internally-driven) goals--a developmental progression that may reflect the greater demands on selection processes inherent in deciding what to do. Three studies investigated the mechanisms supporting endogenous flexibility, using a verbal fluency task in which children generated members of a category and could decide on their own when to switch from one subcategory to another. Children's verbal fluency related to their performance in a more constrained and well-established switching task (Experiment 1), suggesting that the more complex verbal fluency measure taps the flexibility processes of interest. Children's verbal fluency was also linked to their abstract, categorical representations in both individual difference analyses (Experiment 2) and experimental manipulation (Experiment 3). We interpret these results in terms of the role of abstract representations in reducing selection demands to aid the development of endogenous control.

How action and context priming influence categorization: A developmental study

Embodied views of cognition propose that concepts are grounded in sensorimotor experience. Diverse aspects of sensorimotor experience, like action and context information, could play a key role in the formation and processing of manipulable object concepts. Specifically, contextual information could help to link specific actions experienced with different object exemplars. In this study, the effects of action and context priming on superordinate and basic-level categorization of manipulable objects were directly contrasted in 7- and 9-year-olds and in adults. Across the ages, results revealed a differential effect of hand and scene primes on conceptual processing at the superordinate and basic levels; the disadvantage of superordinate over basic-level categorization was reduced in the context priming condition in comparison to the action priming condition. The nature and role of contextual knowledge are discussed from a cognitive and a neurophysiological point of view. Directions for further developmental research on concepts are also considered.

Categorical flexibility in preschoolers: contributions of conceptual knowledge and executive control

The current study evaluated the relative roles of conceptual knowledge and executive control on the development of categorical flexibility, the ability to switch between simultaneously available but conflicting categorical representations of an object. Experiment 1 assessed conceptual knowledge and executive control together; Experiment 2 differentiated conceptual knowledge from costly executive processes. In Experiment 1, 3- to 5-year-olds were given a three-choice (taxonomic, thematic, and nonassociate) match-to-sample task and asked to match two associates. In Experiment 2, same-aged children were assessed on another match-to-sample task that reduced executive costs by presenting thematic and taxonomic associates on separate trials. By comparing performance across tasks, age-related changes resulting from conceptual knowledge and executive control indicated that conceptual knowledge of superordinate relations showed gains between 3 and 4 years, whereas gains in executive control were seen between 4 and 5 years, suggesting a décalage in the development of conceptual and executive processes underlying categorical flexibility.

The influence of category coherence on inference about cross-classified entities

A critical function of categories is their use in property inference (Heit, 2000). However, one challenge to using categories in inference is that most entities in the world belong to multiple categories (e.g., Fido could be a dog, a pet, a mammal, or a security system). Building on Patalano, Chin-Parker, and Ross (2006), we tested the hypothesis that category coherence (the extent to which category features go together in light of prior knowledge) influences the selection of categories for use in property inference about cross-classified entities. In two experiments, we directly contrasted coherent and incoherent categories, both of which included cross-classified entities as members, and we found that the coherent categories were used more readily as the source of both property transfer and property extension. We conclude that category coherence, which has been found to be a potent influence on strength of inference for singly classified entities (Rehder & Hastie, 2004), is also central to category use in reasoning about novel cross-classified ones.

Children's Evaluative Categories and Inductive Inferences within the Domain of Food

Evaluative categories include items that share the same value- laden assessment. Given that these categories have not been examined extensively within the child concepts literature, the present research explored evaluative categorization and induction within the domain of food as a test case. Specifically, two studies examined the categories of healthy and junky foods in children aged 4 and 7 years. Study 1 showed that by aged 4 years, children appropriately apply the evaluative categories of healthy and junky foods to a variety of different foods. Study 2 showed that by age 4 years, children also selectively use the evaluative categories of healthy and junky foods for inductive inferences about the human body, but not for arbitrary or unrelated inferences. Taken together, these results highlight the importance of evaluative processing in young children's categorization and induction.