Can infants be "taught" to attend to a new physical variable in an event category? The case of height in covering events

Causal learning by infants and young children: From computational theories to language practices

Causal reasoning-the ability to reason about causal relations between events-is fundamental to understanding how the world works. This paper reviews two prominent theories on early causal learning and offers possibilities for theory bridging. Both theories grow out of computational modeling and have significant areas of overlap while differing in several respects. Explanation-Based Learning (EBL) focuses on young infants' learning about causal concepts of physical objects and events, whereas Bayesian models have been used to describe causal reasoning beyond infancy across various concept domains. Connecting the two models offers a more integrated approach to clarifying the developmental processes in causal reasoning from early infancy through later childhood. We further suggest that everyday language practices offer a promising space for theory bridging. We provide a review of selective work on caregiver-child conversations, in particular, on the use of scaffolding language including causal talk and pedagogical questions. Linking the research on language practices to the two cognitive theories, we point out directions for further research to integrate EBL and Bayesian models and clarify how causal learning unfolds in real life. This article is categorized under: Psychology > Learning Cognitive Biology > Cognitive Development.

Infants can use temporary or scant categorical information to individuate objects

In a standard individuation task, infants see two different objects emerge in alternation from behind a screen. If they can assign distinct categorical descriptors to the two objects, they expect to see both objects when the screen is lowered; if not, they have no expectation at all about what they will see (i.e., two objects, one object, or no object). Why is contrastive categorical information critical for success at this task? According to the kind account, infants must decide whether they are facing a single object with changing properties or two different objects with stable properties, and access to permanent, intrinsic, kind information for each object resolves this difficulty. According to the two-system account, however, contrastive categorical descriptors simply provide the object-file system with unique tags for individuating the two objects and for communicating about them with the physical-reasoning system. The two-system account thus predicts that any type of contrastive categorical information, however temporary or scant it may be, should induce success at the task. Two experiments examined this prediction. Experiment 1 tested 14-month-olds (N = 96) in a standard task using two objects that differed only in their featural properties. Infants succeeded at the task when the object-file system had access to contrastive temporary categorical descriptors derived from the objects' distinct causal roles in preceding support events (e.g., formerly a support, formerly a supportee). Experiment 2 tested 9-month-olds (N = 96) in a standard task using two objects infants this age typically encode as merely featurally distinct. Infants succeeded when the object-file system had access to scant categorical descriptors derived from the objects' prior inclusion in static arrays of similarly shaped objects (e.g., block-shaped objects, cylinder-shaped objects). These and control results support the two-system account's claim that in a standard task, contrastive categorical descriptors serve to provide the object-file system with unique tags for the two objects.

Intuitive physics learning in a deep-learning model inspired by developmental psychology

'Intuitive physics' enables our pragmatic engagement with the physical world and forms a key component of 'common sense' aspects of thought. Current artificial intelligence systems pale in their understanding of intuitive physics, in comparison to even very young children. Here we address this gap between humans and machines by drawing on the field of developmental psychology. First, we introduce and open-source a machine-learning dataset designed to evaluate conceptual understanding of intuitive physics, adopting the violation-of-expectation (VoE) paradigm from developmental psychology. Second, we build a deep-learning system that learns intuitive physics directly from visual data, inspired by studies of visual cognition in children. We demonstrate that our model can learn a diverse set of physical concepts, which depends critically on object-level representations, consistent with findings from developmental psychology. We consider the implications of these results both for AI and for research on human cognition.

How do the object-file and physical-reasoning systems interact? Evidence from priming effects with object arrays or novel labels

How do infants reason about simple physical events such as containment, tube, and support events? According to the two-system model, two cognitive systems, the object-file (OF) and physical-reasoning (PR) systems, work together to guide infants' responses to these events. When an event begins, the OF system sends categorical information about the objects and their arrangements to the PR system. This system then categorizes the event, assigns event roles to the objects, and taps the OF system for information about features previously identified as causally relevant for the event category selected. All of the categorical and featural information included in the event's representation is interpreted by the PR system's domain knowledge, which includes core principles such as persistence and gravity. The present research tested a novel prediction of the model: If the OF system could be primed to also send, at the beginning of an event, information about an as-yet-unidentified feature, the PR system would then interpret this information using its core principles, allowing infants to detect core violations involving the feature earlier than they normally would. We examined this prediction using two types of priming manipulations directed at the OF system, object arrays and novel labels. In six experiments, infants aged 7-13 months (N = 304) were tested using different event categories and as-yet-unidentified features (color in containment events, height in tube events, and proportional distribution in support events) as well as different tasks (violation-of-expectation and action tasks). In each case, infants who were effectively primed reasoned successfully about the as-yet-unidentified feature, sometimes as early as six months before they would typically do so. These converging results provide strong support for the two-system model and for the claim that uncovering how the OF and PR systems represent and exchange information is essential for understanding how infants respond to physical events.

Analogical Comparison Promotes Theory-of-Mind Development

Theory-of-mind (ToM) is an integral part of social cognition, but how it develops remains a critical question. There is evidence that children can gain insight into ToM through experience, including language training and explanatory interactions. But this still leaves open the question of how children gain these insights-what processes drive this learning? We propose that analogical comparison is a key mechanism in the development of ToM. In Experiment 1, children were shown true- and false-belief scenarios and prompted to engage in multiple comparisons (e.g., belief vs. world). In Experiments 2a, 2b, and 3, children saw a series of true- and false-belief events, varying in order and in their alignability. Across these experiments, we found that providing support for comparing true- and false-belief scenarios led to increased performance on false-belief tests. These findings show that analogical comparison can support ToM learning.

The origins of higher-order thinking lie in children's spontaneous talk across the pre-school years

Higher-order thinking is relational reasoning in which multiple representations are linked together, through inferences, comparisons, abstractions, and hierarchies. We examine the development of higher-order thinking in 64 preschool-aged children, observed from 14 to 58 months in naturalistic situations at home. We used children's spontaneous talk about and with relations (i.e., higher-order thinking talk, or HOTT) as a window onto their higher-order thinking skills. We find that surface HOTT, in which relations between representations are more immediate and easily perceptible, appears before-and is far more frequent than-structure HOTT, in which relations between representations are more abstract and less easy to perceive. Child-specific factors (including early vocabulary and gesture use, first-born status, and family income) predict differences in children's onset (i.e., age of acquisition) of HOTT and its trajectory of use across development. Although HOTT utterances tend to be longer and more syntactically complex than non-HOTT utterances, HOTT frequently appears in non-complex utterances, and a substantial proportion of children achieve complex utterance onset prior to the onset of HOTT. This finding suggests that complex language is neither necessary nor sufficient for HOTT to occur; other factors above and beyond complex linguistic skills are involved in the onset and use of higher-order thinking. Finally, we found that the trajectory of HOTT, particularly structure HOTT-but not complex utterances-during the preschool period predicts standardized outcome measures of inference and analogy skills in grade school, which underscores the crucial role that this kind of early talk plays for later outcomes.

Regularity detection and explanation-based learning jointly support learning about physical events in early infancy

The present research considers statistical learning (SL) and explanation-based learning (EBL) as joint mechanisms to support the development of physical knowledge. Infants watched teaching events in which a cover was lowered over an object and released, with outcomes that violated object principles. The object became fully hidden under a cover that was much shorter, and it remained partly visible under a cover that was much taller. Next, infants watched two test events identical to the teaching events except that one of the events was modified to present a plausible outcome and thus deviated from teaching. Infants at 3.5 months readily detected the regularity in the teaching events and noticed the change in the modified test event, whereas 6.5-month-olds did not. The pattern of response was reversed (1) when 3.5-month-olds were primed to notice the violation of object principles in the teaching events, which interfered with EBL and led infants to miss the change in the modified test event; and (2) when 6.5-month-olds were provided ways to remove the violation from the teaching events, which enabled EBL and led infants to notice the change in the modified test event. Together, the results shed light on young infants' approach to learning about physical events-one that integrates SL for pattern detection and EBL for causal coherence of the rule being learned.

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).

Explanation-based learning in infancy

In explanation-based learning (EBL), domain knowledge is leveraged in order to learn general rules from few examples. An explanation is constructed for initial exemplars and is then generalized into a candidate rule that uses only the relevant features specified in the explanation; if the rule proves accurate for a few additional exemplars, it is adopted. EBL is thus highly efficient because it combines both analytic and empirical evidence. EBL has been proposed as one of the mechanisms that help infants acquire and revise their physical rules. To evaluate this proposal, 11- and 12-month-olds (n = 260) were taught to replace their current support rule (that an object is stable when half or more of its bottom surface is supported) with a more sophisticated rule (that an object is stable when half or more of the entire object is supported). Infants saw teaching events in which asymmetrical objects were placed on a base, followed by static test displays involving a novel asymmetrical object and a novel base. When the teaching events were designed to facilitate EBL, infants learned the new rule with as few as two (12-month-olds) or three (11-month-olds) exemplars. When the teaching events were designed to impede EBL, however, infants failed to learn the rule. Together, these results demonstrate that even infants, with their limited knowledge about the world, benefit from the knowledge-based approach of EBL.

Infants Actively Construct and Update Their Representations of Physical Events: Evidence from Change Detection by 12-Month-Olds

The present research investigates the effects of top-down information on 12-month-olds’ representations of physical events, focusing on their ability to detect an object change across different events. Infants this age typically fail to detect height changes in events with tubes even though they successfully do so in events with covers. In Experiment  1, infants who saw a tube event in which objects did not interact successfully detected a change in an object’s height, suggesting that object interaction affects infants’ categorization of physical events. Experiments 2 and 3 examined the fine-grained process of event representation. In Experiment  2, infants detected the change in the tube event if they were led by pretest exposure to believe that the event was conducted with a cover. In Experiment  3, infants who initially believed so updated their representation if shown a tube before object interaction occurred (but not after). Together, these findings provide new evidence that infants, like older children and adults, actively construct physical events. Whether they notice a change depends on their existing knowledge and the current representation of the event.

Perceptual learning and face processing in infancy

Configural information (spacing between features) contributes to face-processing expertise in adulthood. We examined whether infants can be "trained" to process this information. In Experiment 1, 3.5-month-olds failed to discriminate changes in the spacing between facial features. However, in Experiments 2 and 3, infants processed the same information after being primed with faces in which the spacing was repeatedly altered. Experiment 4 found that priming was not effective with inverted faces or with faces depicting changes in features but not relations among features, indicating that the priming exhibited in Experiments 2 and 3 was specific to upright faces depicting spacing changes. Thus, even young infants who do not readily process facial configural information can be induced to do so through priming. These findings suggest that learning to encode critical structural information contributes to the development of face processing expertise.

Is it a Container? Young Infants' Understanding of Containment Events

The present research examined how certain features of a box affected 4.5-month-old infants' interpretation of containment events the box was involved in. If the box was a regular container, infants did not respond with increased attention when a tall cylinder became fully hidden after being lowered inside the box, consistent with previous research. In contrast, if a three-sided object (the box without its back) replaced the box, or if shown that the box had a removable back, infants were able to detect the height violations, 3 months earlier than they normally would. These results demonstrate how infants' perception or representation of objects interplays with their interpretation of physical events these objects involve in.

Infants' grip strength predicts mu rhythm attenuation during observation of lifting actions with weighted blocks

Research has established that the body is fundamentally involved in perception: bodily experience influences activation of the shared neural system underlying action perception and production during action observation, and bodily characteristics influence perception of the spatial environment. However, whether bodily characteristics influence action perception and its underlying neural system is unknown, particularly in early ontogeny. We measured grip strength in 12-month-old infants and investigated relations with mu rhythm attenuation, an electroencephalographic correlate of the neural system underlying action perception, during observation of lifting actions performed with differently weighted blocks. We found that infants with higher grip strength exhibited significant mu attenuation during observation of lifting actions, whereas infants with lower grip strength did not. Moreover, a progressively strong relation between grip strength and mu attenuation during observation of lifts was found with increased block weight. We propose that this relation is attributable to differences in infants' ability to recognize the effort associated with lifting objects of different weights, as a consequence of their developing strength. Together, our results extend the body's role in perception by demonstrating that bodily characteristics influence action perception by shaping the activation of its underlying neural system.

Functional Activation in the Ventral Object Processing Pathway during the First Year

Infants' capacity to represent objects in visual working memory changes substantially during the first year of life. There is a growing body of research focused on identifying neural mechanisms that support this emerging capacity, and the extent to which visual object processing elicits different patterns of cortical activation in the infant as compared to the adult. Recent studies have identified areas in temporal and occipital cortex that mediate infants' developing capacity to track objects on the basis of their featural properties. The current research (Experiments 1 and 2) assessed patterns of activation in posterior temporal cortex and occipital cortex using fNIRS in infants 3–13 months of age as they viewed occlusion events. In the occlusion events, either the same object or featurally distinct objects emerged to each side of a screen. The outcome of these studies, combined, revealed that in infants 3–6 months, posterior temporal cortex was activated to all events, regardless of the featural properties of the objects and whether the event involved one object or two (featurally distinct) objects. Infants 7–8 infants months showed a waning posterior temporal response and by 10–13 months this response was negligible. Additional analysis showed that the age groups did not differ in their visual attention to the events and that changes in HbO were better explained by age in days than head circumference. In contrast to posterior temporal cortex, robust activation was obtained in occipital cortex across all ages tested. One interpretation of these results is that they reflect pruning of the visual object-processing network during the first year. The functional contribution of occipital and posterior temporal cortex, along with higher-level temporal areas, to infants' capacity to keep track of distinct entities in visual working memory is discussed.

Innate Ideas Revisited: For a Principle of Persistence in Infants' Physical Reasoning

The notion of innate ideas has long been the subject of intense debate in the fields of philosophy and cognitive science. Over the past few decades, methodological advances have made it possible for developmental researchers to begin to examine what innate ideas-what innate concepts and principles-might contribute to infants ' knowledge acquisition in various core domains. This article focuses on the domain of physical reasoning and on Spelke's (1988, 1994) proposal that principles of continuity and cohesion guide infants' interpretation of physical events. The article reviews recent evidence that these two principles are in fact corollaries of a single and more powerful principle of persistence, which states that objects persist, as they are, in time and space.

Prelinguistic Relational Concepts: Investigating Analogical Processing in Infants

This research asks whether analogical processing ability is present in human infants, using the simplest and most basic relation-the same-different relation. Experiment 1 (N = 26) tested whether 7- and 9-month-olds spontaneously detect and generalize these relations from a single example, as previous research has suggested. The attempted replication failed. Experiment 2 asked whether infants could abstract the relation via analogical processing (Experiment 2, N = 64). Indeed, with four exemplars, 7- and 9-month-olds could abstract the same-different relation and generalize it to novel pairs. Furthermore, prior experience with the objects disrupted learning. Facilitation from multiple exemplars and disruption by individual object salience are signatures of analogical learning. These results indicate that analogical ability is present by 7 months.

Bootstrapping the mind: analogical processes and symbol systems

Human cognition is striking in its brilliance and its adaptability. How do we get that way? How do we move from the nearly helpless state of infants to the cognitive proficiency that characterizes adults? In this paper I argue, first, that analogical ability is the key factor in our prodigious capacity, and, second, that possession of a symbol system is crucial to the full expression of analogical ability.

Sex differences during visual scanning of occlusion events in infants

A growing number of sex differences in infancy have been reported. One task on which they have been observed reliably is the event-mapping task. In event mapping, infants view an occlusion event involving 1 or 2 objects, the occluder is removed, and then infants see 1 object. Typically, boys are more likely than girls to detect an inconsistency between a 2-object occlusion event and a 1-object display. The current research investigated underlying reasons for this sex difference. Three eye-tracking experiments were conducted with infants at 9 and 4 months (mean age). Infants saw a ball-box or ball-ball occlusion event followed by a 1-ball display; visual scanning of the occlusion event and the 1-ball display was recorded. Older boys were more likely than older girls to visually track the objects through occlusion and more likely to detect an inconsistency between the ball-box event and the 1-ball display. In addition, tracking objects through occlusion was related to infants' scanning of the 1-ball display. Both younger boys and girls failed to track the objects through occlusion and to detect an inconsistency between the ball-box event and the 1-ball display. These results suggest that infants' capacity to track objects through occlusion facilitates extraction of the structure of the initial event (i.e., the number of distinct objects involved) that infants can map onto the final display and that sex differences in the capacity emerge between 4 and 9 months. Possible explanations for how the structure of an occlusion event is extracted and mapped are considered.

Emerging perception of causality in action-and-reaction sequences from 4 to 6 months of age: is it domain-specific?

Two experiments (N=136) studied how 4- to 6-month-olds perceive a simple schematic event, seen as goal-directed action and reaction from 3 years of age. In our causal reaction event, a red square moved toward a blue square, stopping prior to contact. Blue began to move away before red stopped, so that both briefly moved simultaneously at a distance. Primarily, our study sought to determine from what age infants see the causal structure of this reaction event. In addition, we looked at whether this causal percept depends on an animate style of motion and whether it correlates with tasks assessing goal perception and goal-directed action. Infants saw either causal reactions or noncausal delayed control events in which blue started some time after red stopped. These events involved squares that moved either rigidly or nonrigidly in an apparently animate manner. After habituation to one of the four events, infants were tested on reversal of the habituation event. Spatiotemporal features reversed for all events, but causal roles changed only in reversed reactions. The 6-month-olds dishabituated significantly more to reversal of causal reaction events than to noncausal delay events, whereas younger infants reacted similarly to reversal of both. Thus, perceptual causality for reaction events emerges by 6 months of age, a younger age than previously reported but, crucially, the same age at which perceptual causality for launch events has emerged in prior research. On our second question, animate/inanimate motion had no effect at any age, nor did significant correlations emerge with our additional tasks assessing goal perception or goal-directed object retrieval. Available evidence, here and elsewhere, is as compatible with a view that infants initially see A affecting B, without differentiation into physical or psychological causality, as with the standard assumption of distinct physical/psychological causal perception.

Object Individuation and Physical Reasoning in Infancy: An Integrative Account

Much of the research on object individuation in infancy has used a task in which two different objects emerge in alternation from behind a large screen, which is then removed to reveal either one or two objects. In their seminal work, Xu and Carey (1996) found that it is typically not until the end of the first year that infants detect a violation when a single object is revealed. Since then, a large number of investigations have modified the standard task in various ways and found that young infants succeed with some but not with other modifications, yielding a complex and unwieldy picture. In this article, we argue that this confusing picture can be better understood by bringing to bear insights from a related subfield of infancy research, physical reasoning. By considering how infants reason about object information within and across physical events, we can make sense of apparently inconsistent findings from different object-individuation tasks. In turn, object-individuation findings deepen our understanding of how physical reasoning develops in infancy. Integrating the insights from physical-reasoning and object-individuation investigations thus enriches both subfields and brings about a clearer account of how infants represent objects and events.

Experience matters: 11-month-old infants can learn to use material information to predict the weight of novel objects

In contrast to previous findings, this study demonstrates that 11-month-old infants are able to learn the relationship between object material and object weight when exploring different objects that provided a systematic covariation of both object features. This guides their action in a subsequent preferential-reaching task.

A unified account of abstract structure and conceptual change: Probabilistic models and early learning mechanisms

We need not propose, as Carey does, a radical discontinuity between core cognition, which is responsible for abstract structure, and language and “Quinian bootstrapping,” which are responsible for learning and conceptual change. From a probabilistic models view, conceptual structure and learning reflect the same principles, and they are both in place from the beginning.

Young infants' actions reveal their developing knowledge of support variables: converging evidence for violation-of-expectation findings

Violation-of-expectation (VOE) tasks have revealed substantial developments in young infants' knowledge about support events: by 5.5 months, infants expect an object to fall when released against but not on a surface; and by 6.5 months, infants expect an object to fall when released with 15% but not 100% of its bottom on a surface. Here we investigated whether action tasks would reveal the same developmental pattern. Consistent with VOE reports, 5.5- and 6.5-month-old infants were more likely to reach for a toy that rested on as opposed to against a surface; and 6.5- but not 5.5-month-olds were more likely to reach for a toy with 100% as opposed to 15% of its bottom on a surface. Infants at each age thus used their support knowledge to determine whether the toys were likely to be retrievable or to be attached to adjacent surfaces and hence irretrievable. These and control findings extend recent evidence that developmental patterns observed in VOE tasks also hold in action tasks, and as such provide further support for the view that VOE and action tasks tap the same physical knowledge.

Detecting impossible changes in infancy: a three-system account

Can infants detect that an object has magically disappeared, broken apart or changed color while briefly hidden? Recent research suggests that infants detect some but not other 'impossible' changes; and that various contextual manipulations can induce infants to detect changes they would not otherwise detect. We present an account that includes three systems: a physical-reasoning, an object-tracking, and an object-representation system. What impossible changes infants detect depends on what object information is included in the physical-reasoning system; this information becomes subject to a principle of persistence, which states that objects can undergo no spontaneous or uncaused change. What contextual manipulations induce infants to detect impossible changes depends on complex interplays between the physical-reasoning system and the object-tracking and object-representation systems.

Detecting continuity violations in infancy: a new account and new evidence from covering and tube events

Recent research on infants' responses to occlusion and containment events indicates that, although some violations of the continuity principle are detected at an early age e.g. Aguiar, A., & Baillargeon, R. (1999). 2.5-month-old infants' reasoning about when objects should and should not be occluded. Cognitive Psychology 39, 116-157; Hespos, S. J., & Baillargeon, R. (2001). Knowledge about containment events in very young infants. Cognition 78, 207-245; Luo, Y., & Baillargeon, R. (in press). When the ordinary seems unexpected: Evidence for rule-based reasoning in young infants. Cognition; Wilcox, T., Nadel, L., & Rosser, R. (1996). Location memory in healthy preterm and full-term infants. Infant Behavior & Development 19, 309-323, others are not detected until much later e.g. Baillargeon, R., & DeVos, J. (1991). Object permanence in young infants: Further evidence. Child Development 62, 1227-1246; Hespos, S. J., & Baillargeon, R. (2001). Infants' knowledge about occlusion and containment events: A surprising discrepancy. Psychological Science 12, 140-147; Luo, Y., & Baillargeon, R. (2004). Infants' reasoning about events involving transparent occluders and containers. Manuscript in preparation; Wilcox, T. (1999). Object individuation: Infants' use of shape, size, pattern, and color. Cognition 72, 125-166. The present research focused on events involving covers or tubes, and brought to light additional examples of early and late successes in infants' ability to detect continuity violations. In Experiment 1, 2.5- to 3-month-old infants were surprised (1) when a cover was lowered over an object, slid to the right, and lifted to reveal no object; and (2) when a cover was lowered over an object, slid behind the left half of a screen, lifted above the screen, moved to the right, lowered behind the right half of the screen, slid past the screen, and finally lifted to reveal the object. In Experiments 2 and 3, 9- and 11-month-old infants were not surprised when a short cover was lowered over a tall object until it became fully hidden; only 12-month-old infants detected this violation. Finally, in Experiment 4, 9-, 12-, and 13-month-old infants were not surprised when a tall object was lowered inside a short tube until it became fully hidden; only 14-month-old infants detected this violation. A new account of infants' physical reasoning attempts to make sense of all of these results. New research directions suggested by the account are also discussed.