Infants' categorization of novel objects with more or less obvious features

Relevance and the Role of Labels in Categorization

Language has been shown to influence the ability to form categories. Nevertheless, in most prior work, the effects of language could have been bolstered by the fact that linguistic labels were introduced by the experimenter prior to the categorization task in ways that could have highlighted their relevance for the task. Here, we compared the potency of labels to that of other non-linguistic cues on how people categorized novel, perceptually ambiguous natural kinds (e.g., flowers or birds). Importantly, we varied whether these cues were explicitly presented as relevant to the categorization task. In Experiment 1, we compared labels, numbers, and symbols: One group of participants was told to pay attention to these cues because they would be helpful (Relevant condition), a second group was told that the cues were irrelevant and should be ignored (Irrelevant condition), and a third group was told nothing about the cues (Neutral condition). Even though task relevance affected overall reliance on cues during categorization, participants were more likely to use labels to determine category boundaries, compared to numbers or symbols. In Experiments 2 and 3, we replicated and fine-tuned the advantage of labels in more stringent categorization tasks. These results offer novel evidence for the position that labels offer unique indications of category membership, compared to non-linguistic cues.

Young infants' expectations about a self-propelled agent's body

What intuitive biological understandings do infants have? Recent work reports that 8-month-olds seem to identify self-propelled agents as animals and expect them to have a closed body. The present study examined a group of 6.5-month-old infants' (N = 50, 52% female, 84% White) biological expectations. The infants seemed to grasp the causal link between a novel self-propelled box agent's functioning and its body because they expected a temporary operation (i.e., an experimenter opening the box, exposing its insides, and closing it) to impair its ability to move. Further, infants accepted what was shown inside the box during the operation; whether it had an internal cuboid did not affect the results. Together, this suggests that infants at this young age appear to recognize the importance of having an intact body to a novel self-propelled agent's mobility but have no specific knowledge about what should be inside such an entity. These findings thus shed new light on the developmental origins of biological understandings.

The development of categorisation and conceptual thinking in early childhood: methods and limitations

We present a systematic and qualitative review of academic literature on early conceptual development (0–24 months of age), with an emphasis on methodological aspects. The final sample of our review included 281 studies reported in 115 articles. The main aims of the article were four: first, to organise studies into sets according to methodological similarities and differences; second, to elaborate on the methodological procedures that characterise each set; third, to circumscribe the empirical indicators that different sets of studies consider as proof of the existence of concepts in early childhood; last, to identify methodological limitations and to propose possible ways to overcome them. We grouped the studies into five sets: preference and habituation experiments, category extension tasks, object sorting tasks, sequential touching tasks and object examination tasks. In the “Results” section, we review the core features of each set of studies. In the “Discussion” and “Conclusions” sections, we describe, for one thing, the most relevant methodological shortcomings. We end by arguing that a situated, semiotic and pragmatic perspective that emphasises the importance of ecological validity could open up new avenues of research to better understand the development of concepts in early childhood.

Emotion words, emotion concepts, and emotional development in children: A constructionist hypothesis

In this article, we integrate two constructionist approaches-the theory of constructed emotion and rational constructivism-to introduce several novel hypotheses for understanding emotional development. We first discuss the hypothesis that emotion categories are abstract and conceptual, whose instances share a goal-based function in a particular context but are highly variable in their affective, physical, and perceptual features. Next, we discuss the possibility that emotional development is the process of developing emotion concepts, and that emotion words may be a critical part of this process. We hypothesize that infants and children learn emotion categories the way they learn other abstract conceptual categories-by observing others use the same emotion word to label highly variable events. Finally, we hypothesize that emotional development can be understood as a concept construction problem: a child becomes capable of experiencing and perceiving emotion only when her brain develops the capacity to assemble ad hoc, situated emotion concepts for the purposes of guiding behavior and giving meaning to sensory inputs. Specifically, we offer a predictive processing account of emotional development. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Catastrophic individuation failures in infancy: A new model and predictions

Comparison of infant findings from the physical-reasoning and object-individuation literatures reveals a contradictory picture. On the one hand, physical-reasoning results indicate that young infants can use featural information to guide their actions on objects and to detect interaction violations (when objects interact in ways that are not physically possible) as well as change violations (when objects spontaneously undergo featural changes that are not physically possible). On the other hand, object-individuation results indicate that young infants typically cannot use featural information to detect individuation violations (when the number of objects revealed at the end of an event is less than the number of objects introduced during the event). In this article, we attempt to reconcile these two bodies of research. In a new model of early individuation, we propose that two systems help infants individuate objects in physical events: the object-file and physical-reasoning systems. Under certain conditions, disagreements between the systems result in catastrophic individuation failures, leading infants to hold no expectation at all about how many objects are present. We report experiments with 9- to 11-month-old infants (N = 216) that tested predictions from the model. After two objects emerged in alternation from behind a screen, infants detected no violation when the screen was lowered to reveal no object. Similarly, after two objects emerged in alternation from inside a box, which was then shaken, infants detected no violation when the box remained silent, as though empty. We end with new directions, suggested by our model, for research on early object representations. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Animacy cues facilitate 10-month-olds' categorization of novel objects with similar insides

In this experiment, we examined whether sensitivity to the relevance of object insides for the categorization of animate objects is in place around 10 months of age. Using an object examining paradigm, 10-month-old infants' (N = 58) were familiarized to novel objects with varying outward appearances but shared insides in one of three groups: No cues, Eyes, and Cue control. During test trials, infants were presented with a novel in-category test object followed by an out-of-category test object. When objects were presented with animacy cues (i.e., Eyes), infants categorized the objects together. In contrast, when objects were presented without any added cues or when they were presented with a shared perceptual marker (Cue control, i.e., plastic spoons placed on top of the objects), infants showed no evidence of categorization. These results indicate that by 10 months of age, eyes signal to infants that objects share some kind of uniting commonality that may not be obvious or readily perceptually available.

Infants' agent individuation: It's what's on the insides that counts

Adults and preschool-aged children believe that internal properties are more important than external properties when determining an agent's identity over time. The current study examined the developmental origins of this understanding using a manual-search individuation task with 13-month-old infants. Subjects observed semi-transparent objects that looked and behaved like animate agents placed into box that they could reach but not see into. Across trials infants observed objects with either the same- or different-colored insides placed into the box. We found that infants used internal property differences more than external property differences to determine how many agents were involved in the event. A second experiment confirmed that this effect was specific to the domain of animate entities. These results suggest that infants are biased to see an agent's 'insides' as more important for determining its identity over time than its outside properties.

The influence of labels and facts on children's and adults' categorization

Language has been assumed to influence categorization for both adults and children but the precise role and potency of linguistic labels in category formation remains open. Here we explore how linguistic labels help fit objects into categories when relevant perceptual information is either ambiguous or inconsistent with the labels. We also ask how the effects of labels compare to those of other types of information such as facts. We presented 4-year-old children and adults with tasks in which they had to categorize a perceptually ambiguous natural-kind stimulus with one of two equidistant standards (Exp. 1 and 2) or group an ambiguous natural-kind stimulus into a category with a perceptually dissimilar standard (Exp. 3). Participants had access to labels (e.g., "This one is a lorp/pim"), observable facts (e.g., "This one has a long/short beak"), or unobservable facts (e.g., "This one drinks water/milk") that grouped the ambiguous stimulus with one of the standards. Both children and adults followed label- and fact-driven category boundaries for perceptually ambiguous stimuli (Exp. 1 and 2), and continued to do so even when the labels or facts pointed to perceptually incongruent categories (Exp. 3). These findings suggest a strong causal role for both labels and facts in categorization and have implications about theories of how categorization develops in children.

The inherence heuristic: An intuitive means of making sense of the world, and a potential precursor to psychological essentialism

We propose that human reasoning relies on aninherence heuristic, an implicit cognitive process that leads people to explain observed patterns (e.g., girls wear pink) predominantly in terms of the inherent features of their constituents (e.g., pink is a delicate color). We then demonstrate how this proposed heuristic can provide a unified account for a broad set of findings spanning areas of research that might at first appear unrelated (e.g., system justification, nominal realism, is–ought errors in moral reasoning). By revealing the deep commonalities among the diverse phenomena that fall under its scope, our account is able to generate new insights into these phenomena, as well as new empirical predictions. A second main goal of this article, aside from introducing the inherence heuristic, is to articulate the proposal that the heuristic serves as a foundation for the development of psychological essentialism. More specifically, we propose thatessentialism – which is the common belief that natural and social categories are underlain by hidden, causally powerful essences – emerges over the first few years of life as an elaboration of the earlier, and more open-ended, intuitions supplied by the inherence heuristic. In the final part of the report, we distinguish our proposal from competing accounts (e.g., Strevens's K-laws) and clarify the relationship between the inherence heuristic and related cognitive tendencies (e.g., the correspondence bias). In sum, this article illuminates a basic cognitive process that emerges early in life and is likely to have profound effects on many aspects of human psychology.

From perceptual to language-mediated categorization

From at least two months onwards, infants can form perceptual categories. During the first year of life, object knowledge develops from the ability to represent individual object features to representing correlations between attributes and to integrate information from different sources. At the end of the first year, these representations are shaped by labels, opening the way to conceptual knowledge. Here, we review the development of object knowledge and object categorization over the first year of life. We then present an artificial neural network model that models the transition from early perceptual categorization to categories mediated by labels. The model informs a current debate on the role of labels in object categorization by suggesting that although labels do not act as object features they nevertheless affect perceived similarity of perceptually distinct objects sharing the same label. The model presents the first step of an integrated account from early perceptual categorization to language-based concept learning.

Young infants have biological expectations about animals

What are the developmental origins of our concept of animal? There has long been controversy concerning this question. At issue is whether biological reasoning develops from earlier forms of reasoning, such as physical and psychological reasoning, or whether from a young age children endow animals with biological properties. Here we demonstrate that 8-mo-old infants already expect novel objects they identify as animals to have insides. Infants detected a violation when an object that was self-propelled and agentive (but not an object that lacked one or both of these properties) was revealed to be hollow. Infants also detected a violation when an object that was self-propelled and furry (but not an object that lacked one or both of these properties) either was shown to be hollow or rattled (when shaken) as although mostly hollow. Young infants' expectations about animals' insides may serve as a foundation for the development of more advanced biological knowledge.

Developmental differences in the naming of contextually non-categorical objects

This study investigates the naming process of contextually non-categorical objects in children from 3 to 9 plus 13-year-olds. 112 children participated in the study. Children were asked to narrate a story individually while looking at Mercer Mayer's textless, picture book Frog, where are you? The narratives were audio recorded and transcribed. Texts were analyzed to find out how children at different ages name contextually non-categorical objects, tree and its parts in this case. Our findings revealed that increasing age in children is a positive factor in naming objects that are parts or extended forms of an object which itself constitutes a basic category in a certain context. Younger children used categorical names more frequently to refer to parts or disfigured forms of the object than older children and adults while older children and adults used specified names to refer to the parts or extended forms of the categorical names.

Language and conceptual development

Linguistic and conceptual development converge crucially in the process of early word learning. Acquiring a new word requires the child to identify a conceptual unit, identify a linguistic unit, and establish a mapping between them. On the conceptual side, the child has to not only identify the relevant part of the scene being labeled, but also isolate a concept at the correct level of abstraction-the word 'dog' must be mapped to the concept dog and not to the concepts petting or collie, for example. On the linguistic side, the child must use the syntactic context in which the word appears to determine its grammatical category (e.g., noun, verb, adjective). But she also uses syntactic information, along with observation of the world and social-communicative cues, to make guesses at which concept the word picks out as well as its level of abstraction. We present evidence that young learners learn new words rapidly and extend them appropriately. However, the relative import of observational and linguistic cues varies as a function of the kind of word being acquired, with verbs requiring a richer set of conceptual and linguistic cues than nouns. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.

Five-month-old infants' identification of the sources of vocalizations

Humans speak, monkeys grunt, and ducks quack. How do we come to know which vocalizations animals produce? Here we explore this question by asking whether young infants expect humans, but not other animals, to produce speech, and further, whether infants have similarly restricted expectations about the sources of vocalizations produced by other species. Five-month-old infants matched speech, but not human nonspeech vocalizations, specifically to humans, looking longer at static human faces when human speech was played than when either rhesus monkey or duck calls were played. They also matched monkey calls to monkey faces, looking longer at static rhesus monkey faces when rhesus monkey calls were played than when either human speech or duck calls were played. However, infants failed to match duck vocalizations to duck faces, even though infants likely have more experience with ducks than monkeys. Results show that by 5 months of age, human infants generate expectations about the sources of some vocalizations, mapping human faces to speech and rhesus faces to rhesus calls. Infants' matching capacity does not appear to be based on a simple associative mechanism or restricted to their specific experiences. We discuss these findings in terms of how infants may achieve such competence, as well as its specificity and relevance to acquiring language.

18-Month-olds can perceive Mooney faces

The ability to detect facial information despite poor visual conditions is important for young infants. The present study investigated the developmental course of facial information detection by examining whether infants perceive Mooney faces, a well-studied type of impoverished face image. The 18-month-olds preferred upright Mooney faces to inverted ones, but 12- and 6-month-olds did not show any signs of discriminating the upright Mooney faces from inverted ones. These results indicate that 18-month-olds possess the ability to perceive Mooney faces, but definitive conclusions cannot be drawn regarding the ability to perceive Mooney faces in younger infants.

Biases towards internal features in infants' reasoning about objects

This paper reports the results of two sets of studies demonstrating 14-month-olds' tendency to associate an object's behavior with internal, rather than external features. In Experiment 1 infants were familiarized to two animated cats that each exhibited a different style of self-generated motion. Infants then saw a novel individual that had an internal feature (stomach color) similar to one cat, but an external feature (hat color) similar to the other. Infants looked reliably longer when the individual's motion was congruent with the hat than when it was congruent with the stomach. Using a converging method involving object choice, Experiment 2 found that infants prioritized the internal feature over the external feature only when the object's behavior was self-generated. In the absence of self-generated behaviors, however, infants did not show a preference towards the internal feature.

Words (but not tones) facilitate object categorization: evidence from 6- and 12-month-olds

Recent studies reveal that naming has powerful conceptual consequences within the first year of life. Naming distinct objects with the same word highlights commonalities among the objects and promotes object categorization. In the present experiment, we pursued the origin of this link by examining the influence of words and tones on object categorization in infants at 6 and 12 months. At both ages, infants hearing a novel word for a set of distinct objects successfully formed object categories; those hearing a sequence of tones for the same objects did not. These results support the view that infants are sensitive to powerful and increasingly nuanced links between linguistic and conceptual units very early in the process of lexical acquisition.