Young children's use of functional information to categorize artifacts: three factors that matter

How children come to (not) detect and apply multiple functions for objects: Rethinking perseveration and functional fixedness

Although humans acquire sophisticated and flexible tool-use skills rapidly throughout childhood, young children and adults still show difficulties using the same object for different functions, manifesting in, for example, perseveration or functional fixedness. This paper presents a novel model proposing bottom-up processes taking place during the acquisition of tool-use abilities through active interaction with objects, resulting in two kinds of cognitive representations of an object: a lower-level, action-centered representation and a higher-level, purpose-centered one. In situations requiring the use of an object to attain a goal, the purpose-centered representation is activated quickly, allowing for an immediate detection of suitable tools. In contrast, activation of the action-centered representation is slow and effortful, but comes with the advantage of offering wide-ranging information about the object's features and how they can be applied. This differential availability and activation of action-centered versus purpose-centered representations also contributes to a deeper understanding of the cognitive mechanisms underlying perseveration or functional fixedness during multifunctional tool use. When applied to the teaching and acquisition of tool use, the model indicates that the form in which object-related information is provided determines which of the two object representations is fostered, thereby either facilitating or complicating the flexible application of an object as a tool for different functions.

"Shape bias" goes social: Children categorize people by weight rather than race

Children tend to categorize novel objects according to their shape rather than their color, texture, or other salient properties-known as "shape bias." We investigated whether this bias also extends to the social domain, where it should lead children to categorize people according to their weight (their body shape) rather than their race (their skin color). In Study 1, participants (n = 50 US 4- and 5-year-olds) were asked to extend a novel label from a target object/person to either an object/person who shared the target's shape/weight, color/race, or neither. Children selected the shape-/weight-matched individual over the color-/race-matched individual (dobjects  = 1.58, dpeople  = 0.99) and their shape biases were correlated across the two domains. In Study 2, participants (n = 20 US 4- and 5-year-olds) were asked to extend a novel internal property from a target person to either a person who shared the target's weight, race, or neither. Again, children selected the weight-matched individual (d = 1.98), suggesting they view an individual's weight as more predictive of their internal properties than their race. Overall, results suggest that children's early shape bias extends into the social domain. Implications for weight bias and early social cognition are discussed. RESEARCH HIGHLIGHTS: Preschoolers extend novel labels based on people's weight rather than their race. Preschoolers infer internal features based on people's weight rather than their race. Shape biases are present, and correlated, across the social and object domains.

When Time Shifts the Boundaries: Isolating the Role of Forgetting in Children's Changing Category Representations

In studies of children's categorization, researchers have typically studied how encoding characteristics of exemplars contribute to children's generalization. However, it is unclear whether children's internal cognitive processes alone, independent of new information, may also influence their generalization. Thus, we examined the role that one cognitive process, forgetting, plays in shaping children's category representations by conducting three experiments. In the first two experiments, participants (NExp1=37, Mage=4.02 years; NExp2=32, Mage=4.48 years) saw a novel object labeled by the experimenter and then saw five new objects with between one and five features changed from the learned exemplar. The experimenter asked whether each object was a member of the same category as the exemplar; children saw the five new objects either immediately or after a five-minute delay. Children endorsed category membership at higher rates at immediate test than at delayed test, suggesting that children's category representations became narrower over time. In Experiment 3, we investigated forgetting as a key mechanism underlying the narrowing found in Experiments 1 and 2. We showed participants (NExp3=34, Mage=4.20 years) the same exemplars used in Experiments 1 and 2; then, either immediately or after a five-minute delay, we showed children seven individual object features and asked if each one had been part of the exemplar. Children's accuracy was lower after the delay, showing that they did indeed forget individual features. Taken together, these results show that forgetting plays an important role in changing children's newly-learned categories over time.

Novel objects with causal event schemas elicit selective responses in tool- and hand-selective lateral occipitotemporal cortex

Tool-selective lateral occipitotemporal cortex (LOTC) responds preferentially to images of tools (hammers, brushes) relative to non-tool objects (clocks, shoes). What drives these responses? Unlike other objects, tools exert effects on their surroundings. We tested whether LOTC responses are influenced by event schemas that denote different temporal relations. Participants learned about novel objects embedded in different event sequences. Causer objects moved prior to the appearance of an environmental event (e.g. stars), while Reactor objects moved after an event. Visual features and motor association were controlled. During functional magnetic resonance imaging, participants viewed still images of the objects. We localized tool-selective LOTC and non-tool-selective parahippocampal cortex (PHC) by contrasting neural responses to images of familiar tools and non-tools. We found that LOTC responded more to Causers than Reactors, while PHC did not. We also measured responses to images of hands, which elicit overlapping responses with tools. Across inferior temporal cortex, voxels' tool and hand selectivity positively predicted a preferential response to Causers. We conclude that an event schema typical of tools is sufficient to drive LOTC and that category-preferential responses across the temporal lobe may reflect relational event structures typical of those domains.

"I know it's complicated": Children detect relevant information about object complexity

Mechanistic complexity is an important property that affects how we interact with and learn from artifacts. Although highly complex artifacts have only recently become part of human material culture, they are ever-present in contemporary life. In previous research, children successfully detected complexity contrasts when given information about the functions of simple and complex objects. However, whether children spontaneously favor relevant information about an object's causal mechanisms and functions when trying to determine an object's complexity remains an open question. In Study 1, 7- to 9-year-olds and adults, but not 5- and 6-year-olds, rated information about relevant actions (e.g., the difficulty in fixing an object) as more helpful than information about irrelevant actions (e.g., the difficulty in spelling an object's name) for making determinations of mechanistic complexity. Only in Study 2, in which the relevance contrasts were extreme, did the youngest age group rate relevant actions as more helpful than irrelevant actions. In Study 3, in which participants rated the complexity of the actions themselves, participants performed differently than in the previous studies, suggesting that children in the prior studies did not misinterpret the study instructions as prompts to rate the actions' complexity. These results suggest that the ability to detect which object properties imply complexity emerges during the early school years. Younger children may be misled by features that are not truly diagnostic of mechanistic complexity, whereas older children more easily disregard such features in favor of relevant information.

From the structure of experience to concepts of structure: How the concept "cause" is attributed to objects and events

The pervasive presence of relational information in concepts, and its indirect presence in sensory input, raises the question of how it is extracted from experience. We operationalized experience as a stream of events in which reliable predictive relationships exist among random ones, and in which learners are naïve as to what they will learn (i.e., a statistical learning paradigm). First, we asked whether predictive event pairs would spontaneously be seen as causing each other, given no instructions to evaluate causality. We found that predictive information indeed informed later causal judgments but did not lead to a spontaneous sense of causality. Thus, event contingencies are relevant to causal inference, but such interpretations may not occur fully bottom-up. A second question was how such experience might be used to learn about novel objects. Because events occurred either around or involving a continually present object, we were able to distinguish objects from events. We found that objects can be attributed causal properties by virtue of a higher-order structure, in which the object's identity is linked not to the increased likelihood of its effect, but rather, to the predictive structure among events, given its presence. This is an important demonstration that objects' causal properties can be highly abstract: They need not refer to an occurrence of a sensory event per se, or its link to an object, but rather to whether or not a predictive relationship holds among events in its presence. These learning mechanisms may be important for acquiring abstract knowledge from experience. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The what and the how: Information-seeking pointing gestures facilitate learning labels and functions

Infants' pointing gestures are clear and salient markers of their interest. As a result, they afford infants with a targeted and precise way of eliciting information from others. The current study investigated whether, similar to older children's question asking, infants' pointing gestures are produced to obtain information. Specifically, in a single experimental study, we examined whether 18-month-olds (N = 36) point to request specific types of information and how this translates into learning across domains. We elicited pointing from infants in a context that would naturally lend itself to information seeking (i.e., out-of-reach novel objects). In response to infants' points, an experimenter provided a label, a function, or no information for each pointed-to object. We assessed infants' persistence after receiving different types of information and their subsequent ability to form label-object or function-object associations. When infants pointed and received no information or functions, they persisted significantly more often than when they pointed and received labels, suggesting that they were most satisfied with receiving labels for objects compared with functions or no information. Infants successfully mapped both labels and functions onto objects. When infants expressed their interest in a novel object in a manner other than pointing, such as reaching, they (a) were equally satisfied with receiving object labels, functions, or no information and (b) did not successfully learn either labels or functions. Together, these findings demonstrate that infants' pointing gestures are specific requests for labels that facilitate the acquisition of various types of information. In doing so, this work connects the research on information seeking during infancy to the established literature on question asking during childhood.

The emerging causal understanding of institutional objects

Institutional objects, such as money, drivers' licenses, and borders, have functions because of their social roles rather than their immediate physical properties. These objects are causally different than standard artifacts (e.g. hammers, chairs, and cars), sharing more commonality with other social roles. Thus, they inform psychological theories of human-made objects as well as children's emerging understanding of social reality. We examined whether children (N=180, ages 4-9) differentiate institutional objects from standard artifacts. Specifically, we examine whether children understand that mutual intentions (i.e., the intentions of a social collective) underlie the functional affordances of institutional objects in ways that they do not for standard artifacts. We find that young children assimilate institutional objects into their intuitive theories of standard artifacts; children begin to differentiate between the domains in the elementary school years.

When Children Ask, “What Is It?” What Do They Want to Know About Artifacts?

When children ask, “What is it?” are they seeking information about what something is called or what kind of thing it is? To find out, we gave 2-, 3-, and 4-year-olds (32 at each age) the opportunity to inquire about unfamiliar artifacts. An ambiguous question was answered with a name or with functional information, depending on the group to which the children were assigned. Children were inclined to follow up with additional questions about the object when they had been told its name, but seemed satisfied with the answer when they had been told the object's function. Moreover, children in the name condition tended to substitute questions about function for ambiguous questions over the course of the session. These results indicate that children are motivated to discover what kinds of things novel artifacts are, and that young children, like adults, conceive of artifact kinds in terms of their functions.

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.

On the other hand: Increased cortical activation to human versus mechanical hands in infants

There is a large body of work demonstrating that infants are sensitive to the distinction between human and mechanical entities from the early months of life, and have different expectations for the way these entities move and interact. The current work investigates the extent to which the functional organization of the immature brain reflects these early emerging sensitivities. Infants aged 8months watched two kinds of hands (human or mechanical) engage in two kinds of events (one with a functional outcome and one without). Using functional near-infrared spectroscopy (fNIRS), we assessed hemodynamic activation in the left and right temporal and temporal-occipital cortex in response to these events. The neuroimaging data revealed a significantly greater increase in activation in the right middle-posterior temporal cortex to events executed by the human than the mechanical hand; the event in which the hand engaged (function or non-function) did not significantly influence hemodynamic responses. In comparison, the left middle-temporal cortex showed significantly greater activation to events executed by the human than mechanical hand, but only when the events were functionally relevant. That is, the left middle-posterior temporal cortex responded selectively to human (as compared to mechanical) agents, but only in the context of functionally relevant actions on objects. These results reveal that the immature brain is functionally specialized to support infants' processing of human and non-human agents as distinct entities. These results also shed light on the cognitive and cortical mechanisms that guide infants' learning about agentive action and object function.

Conditions Under Which Function Information Attenuates Name Extension via Shape

Children often extend names to novel artifacts on the basis of overall shape rather than core properties (e.g., function). This bias is claimed to reflect the fact that nonrandom structure is a reliable cue to an object having a specific designed function. In this article, we show that information about an object's design (i.e., about its creator's intentions) is neither necessary nor sufficient for children to override the shape bias. Children extend names on the basis of any information specifying the artifact's function (e.g., information about design, current use, or possible use), especially when this information is made salient when candidate objects for extension are introduced. Possible mechanisms via which children come to rely less on easily observable cues (e.g., shape) and more on core properties (e.g., function) are discussed.

The Role of Dimensional Distinctiveness in Children's and Adults' Artifact Categorization

There are conflicting results as to whether preschool children categorize artifacts on the basis of physical or functional similarity. The present study investigated the effect of the relative distinctiveness of these dimensions in children's categorization. In a physical-distinctive condition, preschool children and adults were initially asked to categorize computer-animated artifacts whose physical appearances were more distinctive than their functions. In a function-distinctive condition, the functional dimension of objects was more distinctive than their physical appearances. Both conditions included a second stage of categorization in which both dimensions were equally distinctive. Participants in a control condition performed only this stage of categorization. Adults in all conditions and stages consistently categorized by functional similarity. In contrast, children's categorization was affected by the relative distinctiveness of the dimensions. Children may not have a priori specific beliefs about how to categorize novel artifacts, and thus may be more susceptible to contextual factors.

Are Children with Autism Spectrum Disorder Initially Attuned to Object Function Rather Than Shape for Word Learning?

We investigate the function bias—generalising words to objects with the same function—in typically developing (TD) children, children with autism spectrum disorder (ASD) and children with other developmental disorders. Across four trials, a novel object was named and its function was described and demonstrated. Children then selected the other referent from a shape match (same shape, different function) and function match (same function, different shape) object. TD children and children with ASD were ‘function biased’, although further investigation established that having a higher VMA facilitated function bias understanding in TD children, but having a lower VMA facilitated function bias understanding in children with ASD. This suggests that children with ASD are initially attuned to object function, not shape.

Nonmotor aspects of action concepts

Reading an action verb elicits the retrieval of its associated body movements as well as its typical goal-the outcome to which it is directed. Two fMRI experiments are reported in which retrieval of goal attributes was isolated from retrieval of motoric ones by contrasting actions that are either done intentionally (e.g., drink) and thus have associated goal information or by accident (e.g., hiccup). Orthogonally, the actions also varied in their motoricity (e.g., drink vs. imagine). Across both levels of motoricity, goal-directedness influenced the activity of a portion of left posterior inferior parietal lobe (pIPL). These effects were not explicable by the grammatical properties, imageability, or amount of body movement associated with these different types of verbs. In contrast, motoricity (across levels of goal-directedness) activated primarily the left middle temporal gyrus. Furthermore, pIPL was found to be distinct from the portion of left parietal lobe implicated in theory of mind, as localized in the same participants. This is consistent with the observation that pIPL contains many functionally distinct subregions and that some of these support conceptual knowledge. The present findings illustrate that, in particular, the pIPL is involved in representing attributes of intentional actions, likely their typical goals, but not their associated body movements. This result serves to describe an attribute-selective semantic subsystem for at least one type of nonmotor aspect of action knowledge.

Conceptually coherent categories support label-based inductive generalization in preschoolers

Why do words support inductive generalization in preschoolers? The current study provides evidence that they do so, at least in part, by working with conceptual knowledge to establish kind membership. A sample of 30 4-year-olds learned new labels for novel items, sometimes along with additional non-obvious information, and were then asked to generalize a novel object property to a target item based on either visual similarity or shared label. Children were more likely to generalize properties based on shared labels (over perceptual similarity) if they initially learned causally coherent properties of items referenced by those labels than if they initially learned non-causal properties of those items or learned no properties at all. This finding suggests that novel words best support inductive inference when they are known by children to reference conceptually coherent categories. Therefore, conceptual information permeates the process of inductive inference in young children. Results are discussed with respect to their implications for the "word-as-feature" and "knowledge-based" accounts of early inductive inference.

Development of adaptive tool-use in early childhood: sensorimotor, social, and conceptual factors

Tool-use is specialized in humans, and juvenile humans show much more prolific and prodigious tool-use than other juvenile primates. Nonhuman primates possess many of the basic motor and behavioral capacities needed for manual tool-use: perceptual-motor specialization, sociocultural practices and interactions, and abstract conceptualization of kinds of functions, both real and imagined. These traits jointly contribute to the human specialization for tool-using. In particular, from 2 to 5 years of age children develop: (i) more refined motor routines for interacting with a variety of objects, (ii) a deeper understanding and awareness of the cultural context of object-use practices, and (iii) a cognitive facility to represent potential dynamic human-object interactions. The last trait, which has received little attention in recent years, is defined as the ability to form abstract (i.e., generalizable to novel contexts) representations of kinds of functions, even with relatively little training or instruction. This trait might depend not only on extensive tool-using experience but also on developing cognitive abilities, including a variety of cognitive flexibility: specifically, imagistic memory for event sequences incorporating causal inferences about mechanical effects. Final speculations point to a possible network of neural systems that might contribute to the cognitive capacity that includes sensorimotor, sensory integration, and prefrontal cortical resources and interconnections.

Inference and coherence in causal-based artifact categorization

In four experiments, we tested conditions under which artifact concepts support inference and coherence in causal categorization. In all four experiments, participants categorized scenarios in which we systematically varied information about artifacts' associated design history, physical structure, user intention, user action and functional outcome, and where each property could be specified as intact, compromised or not observed. Consistently across experiments, when participants received complete information (i.e., when all properties were observed), they categorized based on individual properties and did not show evidence of using coherence to categorize. In contrast, when the state of some property was not observed, participants gave evidence of using available information to infer the state of the unobserved property, which increased the value of the available information for categorization. Our data offers answers to longstanding questions regarding artifact categorization, such as whether there are underlying causal models for artifacts, which properties are part of them, whether design history is an artifact's causal essence, and whether physical appearance or functional outcome is the most central artifact property.

Can semantic enrichment lead to naming in a word extension task?

PURPOSE

This study examined the relationship between semantic enrichment and naming in children asked to extend taught words to untrained exemplars.

METHOD

Sixteen typically developing children ( M = 32.63 months, SD = 4.02) participated in 3 word learning conditions that varied semantic enrichment via iconic (shape, function) or point gesture. At test, children named taught referents and 2 exemplars of each taught object: shape similar and shape dissimilar. Naming accuracy and errors were analyzed between conditions.

RESULTS

The point condition never outperformed the shape or function conditions. In naming taught words, the shape condition was superior to the point condition, whereas the function condition was only marginally superior to the point condition. However, in naming untrained exemplars, only the shape condition was superior to the point condition, and there were fewer indeterminate errors in the shape condition.

CONCLUSION

Semantic enrichment supports naming, but shape cues appear to be particularly effective in using words beyond just-taught referents.

Information sources for noun learning

Why are some words easier to learn than others? And what enables the eventual learning of the more difficult words? These questions were addressed for nouns using a paradigm in which adults were exposed to naturalistic maternal input that was manipulated to simulate access to several different information sources, both alone and in combination: observation of the extralinguistic contexts in which the target word was used, the words that co-occurred with the target word, and the target word's syntactic context. Words that were not accurately identified from observation alone were both abstract (e.g., music) and concrete (e.g., tail). Whether a noun could be learned from observation depended on whether it labeled a basic-level object category (BLOC). However, the difference between BLOC labels and non-BLOC labels was eliminated when observation was supplemented with linguistic context. Thus, although BLOC labels can be learned from observation alone, non-BLOC labels require richer linguistic context. These findings support a model of vocabulary growth in which an important role is played by changes in the information to which learners have access.

Functions in biological kind classification

Biological traits that serve functions, such as a zebra's coloration (for camouflage) or a kangaroo's tail (for balance), seem to have a special role in conceptual representations for biological kinds. In five experiments, we investigate whether and why functional features are privileged in biological kind classification. Experiment 1 experimentally manipulates whether a feature serves a function and finds that functional features are judged more diagnostic of category membership as well as more likely to have a deep evolutionary history, be frequent in the current population, and persist in future populations. Experiments 2-5 reveal that these inferences about history, frequency, and persistence account for nearly all the effect of function on classification. We conclude that functional features are privileged because their relationship with the kind is viewed as stable over time and thus as especially well suited for establishing category membership, with implications for theories of classification and folk biological understanding.

Preschoolers' novel noun extensions: shape in spite of knowing better

We examined the puzzling research findings that when extending novel nouns, preschoolers rely on shape similarity (rather than categorical relations) while in other task contexts (e.g., property induction) they rely on categorical relations. Taking into account research on children’s word learning, categorization, and inductive inference we assume that preschoolers have both a shape-based and a category-based word extension strategy available and can switch between these two depending on which information is easily available. To this end, we tested preschoolers on two versions of a novel-noun label extension task. First, we paralleled the standard extension task commonly used by previous research. In this case, as expected, preschoolers predominantly selected same-shape items. Second, we supported preschoolers’ retrieval of item-related information from memory by asking them simple questions about each item prior to the label extension task. Here, they switched to a category-based strategy, thus, predominantly selecting same-category items. Finally, we revealed that this shape-to-category shift is specific to the word learning context as we did not find it in a non-lexical classification task. These findings support our assumption that preschoolers’ decision about word extension change in accordance with the availability of information (from task context or by memory retrieval). We conclude by suggesting that preschoolers’ noun extensions can be conceptualized within the framework of heuristic decision-making. This provides an ecologically plausible processing account with respect to which information is selected and how this information is integrated to act as a guideline for decision-making when novel words have to be generalized.

Psychological essentialist reasoning and perspective taking during reading: a donkey is not a zebra, but a plate can be a clock

In an eyetracking study, we examined whether readers use psychological essentialist reasoning and perspective taking online. Stories were presented in which an animal or an artifact was transformed into another animal (e.g., a donkey into a zebra) or artifact (e.g., a plate into a clock). According to psychological essentialism, the essence of the animal did not change in these stories, while the transformed artifact would be thought to have changed categories. We found evidence that readers use this kind of reasoning online: When reference was made to the transformed animal, the nontransformed term ("donkey") was preferred, but the opposite held for the transformed artifact ("clock" was read faster than "plate"). The immediacy of the effect suggests that this kind of reasoning is employed automatically. Perspective taking was examined within the same stories by the introduction of a novel story character. This character, who was naïve about the transformation, commented on the transformed animal or artifact. If the reader were to take this character's perspective immediately and exclusively for reference solving, then only the transformed term ("zebra" or "clock") would be felicitous. However, the results suggested that while this character's perspective could be taken into account, it seems difficult to completely discard one's own perspective at the same time.

Priming infants to use pattern information in an object individuation task: the role of comparison

There is evidence that 4.5-month-olds do not always use surface pattern to individuate objects but that they can be primed to attend to pattern differences through select experiences. For example, if infants are first shown events in which the pattern of an object predicts its function (dotted containers pound and striped containers pour), they will attend to pattern differences in a subsequent individuation task. However, 4.5-month-olds must see multiple exemplars of the pound and pour events and view the dotted and striped containers together during the events. These results suggest that it is the formation of event categories, in which pattern is linked to object function, that supports pattern priming and that direct comparison of the exemplars facilitates the extraction of event categories. The present research investigated conditions that support the comparison process in 4.5-month-olds. The results revealed that the comparison process was initiated only when the dotted and striped containers were seen directly adjacent to each other; if the containers sat far apart, so that infants had to shift their gaze to compare them, event categories were not extracted. In addition, it was comparison of the two patterned containers, and not comparison of the two function events, that was critical to the formation of event categories. These results join a growing body of research indicating the importance of comparison to category formation in infants and reveal the impact of categorization and comparison processes on object individuation in infancy.

Mutual exclusivity in autism spectrum disorders: testing the pragmatic hypothesis

While there is ample evidence that children treat words as mutually exclusive, the cognitive basis of this bias is widely debated. We focus on the distinction between pragmatic and lexical constraints accounts. High-functioning children with autism spectrum disorders (ASD) offer a unique perspective on this debate, as they acquire substantial vocabularies despite impoverished social-pragmatic skills. We tested children and adolescents with ASD in a paradigm examining mutual exclusivity for words and facts. Words were interpreted contrastively more often than facts. Word performance was associated with vocabulary size; fact performance was associated with social-communication skills. Thus mutual exclusivity does not appear to be driven by pragmatics, suggesting that it is either a lexical constraint or a reflection of domain-general learning processes.

Specifying the role of function in infant categorization

Research demonstrates that object functions facilitate artifact categorization in infancy. To explicate the nature and magnitude of this effect, 16-month-olds participated in three studies. In Experiment 1, categorization was facilitated more by object functions than by distinctive motions, suggesting that the motion properties of function cannot fully explain its influence. In Experiment 2, infants failed to categorize when each category exemplar performed a different function, thus revealing the importance of shared functionality in facilitating categorization. In Experiment 3, infants were tested after each new exemplar was introduced. When object functions were provided during training, infants were more likely to appropriately extend the novel categories on the very first trial. This suggests that function reduces the need for exposure to multiple exemplars in forming categories. Together, these findings confirm the conceptual nature of the facilitative effect of function on early categorization.

Infant object categorization transcends diverse object-context relations

Infants' categorization of objects in different object-context relations was investigated. The experiment used a multiple-exemplar habituation-categorization procedure where 92 6-month olds formed categories of animals and vehicles embedded in congruent, incongruent, and homogeneous object-context relations. Across diverse object-context relations, infants habituated to multiple exemplars within a category and categorized novel members of both animal and vehicle categories. Infants showed a slight advantage for categorizing animals. Infant object categorization appears to be robust to diversity in object-context relations.

Young children’s extension of novel labels to novel animate items in three testing conditions

The present research explores young children’s extension of novel labels to novel animate items. Three experiments were performed by means of the intermodal preferential looking (IPL) paradigm. In Experiment 1, after repeated exposure to novel word—object associations, 24- and 36-month-olds extend novel labels on the basis of shape similarity, in a task that pits a match in shape against a match in color. Experiment 2 finds 24-month-olds’ rapid reliance on shape, when introducing simplified trials that required identifying a match in shape or color separately. Experiment 3 reassesses young children’s ability to weigh up two perceptual cues, but in a condition in which the standard item remains visible, demonstrating 18- and 24-month-olds’ use of shape to extend novel labels. In contrast to previous research reporting an early shape bias mainly for inanimate items, this paper reveals that young children also consider shape to be a relevant cue to generalize novel labels to novel animate items. However, memory and processing demands appear to be crucial in the early ability to use shape information to extend novel labels to novel animate stimuli.