Early word learning is influenced by physical environments

During word learning moments, toddlers experience labels and objects in particular environments. Do toddlers learn words better when the physical environment creates contrasts between objects with different labels? Thirty-six 21- to 24-month-olds (92% White, 22 female, data collected 8/21-4/22) learned novel words for novel objects presented using an apparatus that mimicked a shape-sorter toy. The manipulation concerned whether or not the physical features of the environments in which objects occurred heightened the contrasts between the objects. Toddlers only learned labels for objects presented in environments where the apparatus heightened the contrast between the objects (b = .068). These results emphasize the importance of investigating word learning in physical environments that more closely approximate young children's everyday experiences with objects.

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.

Effects of context variability on 2-year-olds' fact and word learning

The current study investigated the effects of context variability on 2.5-year-olds' (N = 48) fact and word learning. Children were taught labels or facts for novel objects that were presented on variable or consistent background contexts during training. At test, children were asked to select target items in a context that either matched training contexts or was entirely new. Children learned words at above-chance levels regardless of context variability, and there was no significant difference in learning between children in variable and consistent training conditions. For facts, on the other hand, children demonstrated above-chance target selection only when contexts matched between training and test. In addition, children's immediate target selection was lower in the variable context condition than in the consistent one. However, this difference was not present after a 10-min delay. Results are discussed in terms of why fact learning and word learning may be differentially affected by context variability.

Causally-Rich Group Play: A Powerful Context for Building Preschoolers' Vocabulary

This work explores whether the facilitative effect of causal information on preschoolers’ word learning observed in the laboratory might be relevant to boosting children’s vocabulary in a group-play context. Forty-eight 3- to 4-year-old children learned six novel words for novel tools introduced during a small group-play session. Half of the groups used the tools according to their specified function to construct a fruit salad. The remaining children used the same tools to decorate a castle of blocks. In this way, some children learned about the causal properties of the tools, while others did not. Although children in both conditions comprehended the novel words equally well when tested shortly after the play session, learning in the Causal condition was more robust. Children’s comprehension scores in the Causal condition increased over time (a 7–20 day delay), such that children in this group performed better than children in the Non-Causal condition when tested in a follow-up session. These results demonstrate a striking benefit of causal enrichment to word learning in a context that could feasibly be implemented in preschool classrooms, playgroups, and individual households. Highlighting the causal properties of objects during playtime might offer a powerful approach to building children’s vocabulary, thereby providing a stronger foundation for early literacy and success in school more generally speaking.

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.

Visual Categorization with Random Projection

Humans learn categories of complex objects quickly and from a few examples. Random projection has been suggested as a means to learn and categorize efficiently. We investigate how random projection affects categorization by humans and by very simple neural networks on the same stimuli and categorization tasks, and how this relates to the robustness of categories. We find that (1) drastic reduction in stimulus complexity via random projection does not degrade performance in categorization tasks by either humans or simple neural networks, (2) human accuracy and neural network accuracy are remarkably correlated, even at the level of individual stimuli, and (3) the performance of both is strongly indicated by a natural notion of category robustness.

Object processing in the infant: lessons from neuroscience

Object identification is a fundamental cognitive capacity that forms the basis for complex thought and behavior. The adult cortex is organized into functionally distinct visual object-processing pathways that mediate this ability. Insights into the origin of these pathways have begun to emerge through the use of neuroimaging techniques with infant populations. The outcome of this work supports the view that, from the early days of life, object-processing pathways are organized in a way that resembles that of the adult. At the same time, theoretically important changes in patterns of cortical activation are observed during the first year. These findings lead to a new understanding of the cognitive and neural architecture in infants that supports their emerging object-processing capacities.

Shared function knowledge: infants' attention to function information in communicative contexts

Humans are specifically adapted to knowledge acquisition and transfer by social communication. According to natural pedagogy theory, infants are highly sensitive to signals that indicate a teacher's communicative intention and are biased to interpret communicative contexts as conveying relevant and generalizable knowledge that is also shared by other conspecifics. We investigated whether infants as young as 12 months interpret ostensively communicated object-directed emotion expressions as generalizable and shareable with others. Given that young infants pay particular attention to information about objects' functions, we were interested in whether the shareability assumption also holds for emotional attitudes toward functional features of unfamiliar objects. The results suggest that 12-month-olds (N=80) flexibly interpret another person's emotion displays toward unfamiliar artifacts either as object-centered and generalizable attitudes or as person-centered subjective attitudes, depending on the communicative characteristics of the learning context. Furthermore, the transfer of ostensively communicated information about the artifacts depended on their functional usability, which is consistent with infants' early sensitivity to function information in various areas of cognitive development.

Learning how actions function: the role of outcomes in infants' representation of events

Action is a fundamental component of object representations. However, little is known about how infants represent actions performed on objects. Across four experiments, we tested the hypothesis that at 10 months of age (N=80) infants represent the general ability of actions to produce outcomes (sounds). Experiments 1A and 1B showed that infants encode actions and associate actions and object appearances in events in which actions produced no sound outcomes. Experiment 2 showed that infants associate the presence or absence of outcomes with actions. Experiment 3 showed, in contrast, that infants did not associate the presence or absence of outcomes with object appearances. Together, these studies suggest that infants encode the outcome potential of specific actions. We discuss the implications of these findings for our understanding of the development of action representations.

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.

Functional understanding facilitates learning about tools in human children

Human children benefit from a possibly unique set of adaptations facilitating the acquisition of knowledge about material culture. They represent artifacts (human-made objects) as tools with specific functions and seek for functional information about novel objects. Even young infants pay attention to functionally relevant features of objects, and learn tool use and infer tool functions from others' goal-directed actions and demonstrations. Children tend to imitate causally irrelevant elements of tool use demonstrations, which helps them to acquire means actions even before they fully understand their causal role in bringing about the desired goal. Although non-human animals use and make tools, and recognize causally relevant features of objects in a given task, they - unlike human children - do not appear to form enduring functional representations of tools as being for achieving particular goals when they are not in use.

Tight and loose are not created equal: an asymmetry underlying the representation of fit in English- and Korean-speakers

Research concerning the spatial dimension fit (tight versus loose) has been based on a tacit but untested assumption that the dimension fit is symmetrical, with tight- and loose-fitting relations highlighting the dimension fit with equal force. We propose a reformulation, documenting that adult speakers of English (Experiment 1) and Korean (Experiment 2) are sensitive to the dimension fit, but that their representation is asymmetric, with tight-fitting events highlighting fit with greater force than loose-fitting events. We propose that sensitivity to the dimension fit is more resilient than has previously been suggested, and that the asymmetry documented here provides a foundation upon which to pursue nuanced questions about the relationship between language and our underlying representations of space.

Color-function categories that prime infants to use color information in an object individuation task

There is evidence for developmental hierarchies in the type of information to which infants attend when reasoning about objects. Investigators have questioned the origin of these hierarchies and how infants come to identify new sources of information when reasoning about objects. The goal of the present experiments was to shed light on this debate by identifying conditions under which infants' sensitivity to color information, which is slow to emerge, could be enhanced in an object individuation task. The outcome of Experiment 1 confirmed and extended previous reports that 9.5-month-olds can be primed, through exposure to events in which the color of an object predicts its function, to attend to color differences in a subsequent individuation task. The outcomes of Experiments 2-4 revealed age-related changes in the nature of the representations that support color priming. This is exemplified by three main findings. First, the representations that are formed during the color-function events are relatively specific. That is, infants are primed to use the color difference seen in the color-function events to individuate objects in the test events, but not other color differences. Second, 9.5-month-olds can be led to form more abstract event representations, and then generalize to other colors in the test events if they are shown multiple pairs of colors in the color-function events. Third, slightly younger 9-month-olds also can be led to form more inclusive categories with multiple color pairs, but only when they are allowed to directly compare the exemplars in each color pair during the present events. These results shed light on the development of categorization abilities, cognitive mechanisms that support color-function priming, and the kinds of experiences that can increase infants' sensitivity to color information.