Infants attend to what happens at the rim when they perceive containment

A series of experiments revealed that 9- and 12-month-old infants, in contrast to 6-month-olds, paid attention to what was happening at the rim of a container when a block arrived at this opening. The rim of an enclosure marks the boundaries of containment for an object, and thus specifies an important source of information with respect to the event. Infants actually observed a solid block that repeatedly lowered into a container in both the habituation phase and in the test phase. In the test phase, infants looked longer to events showing a block that miraculously passed through the opening, although colliding against the rim on one to three places than to the same event without collision. This effect occurred depending on the number of places on the rim the block collided against and the age of the infant. However longer looking times did not show up when the block collided against a flexible rim, deforming this rim and passed through. Together, these results indicate that infants sample information that is meaningful to the event they see and that it is not the perceptual discrepancy with respect to the habitation phase that drives their looking in the test phase.     

Identification of objects in 9‐month‐old infants: integrating ‘what’ and ‘where’ information

Following Leslie, Xu, Tremoulet and Scholl (1998) , we distinguish between individuation (the establishment of an object representation) and identification (the use of information stored in the object representation to decide which previously individuated object is being encountered). Although there has been much work on how infants individuate objects, there is relatively little on the question of when and how property information is used to identify objects. Experiment 1 shows that 9‐month‐old infants use shape, but apparently not color, information in identifying objects that are each moved behind spatially separated screens. Infants could not simply have associated a shape with a location or a screen without regard to objecthood, because on alternate trials the objects switched locations/screens. Infants therefore had to bind shape information to the object representation while tracking the objects’ changing location. In Experiment 2, we tested if infants represented both objects rather than ‘sampled’ only one of them. Using the same alternation procedure, infants again succeeded in using shape (but not color) information when only one of the screens was removed – the screen that occluded the first‐hidden object (requiring the longer time in memory). Finally, we relate our behavioral findings both to a cognitive model and to recent neuroscientific studies, concluding that ventral ‘what’ and dorsal ‘where’ pathways may be functionally integrated by 9 months.     

Reasoning about collisions involving inert objects in 7.5‐month‐old infants

The present research asked whether 7.5‐month‐old infants realize that an object cannot displace another object without contacting it. The infants in Experiment 1 were assigned to a contact or a no‐contact condition. The infants in the no‐contact condition saw static familiarization displays in which a tall, thin barrier stood across the bottom of a ramp; a cylinder rested against the left side of the barrier and a wheeled toy bug against its right side. The infants in the contact condition saw similar displays except that a large portion of the barrier’s lower half was removed so that the cylinder rested directly against the bug. Next, a small screen was placed in front of the bottom of the ramp; only the upper portion of the barrier was visible above the screen. The infants in the two conditions watched the same test event. The cylinder was released and rolled to the bottom of the ramp, partly disappearing behind the screen’s left edge; next, the bug rolled down the track, as though launched by the cylinder. The infants in the no‐contact condition looked reliably longer at the test event than did those in the contact condition. This result suggested that the infants (a) viewed the bug as an inert object that could move only when acted upon; (b) believed that the cylinder could not act on the bug without contacting it; (c) realized that the cylinder could contact the bug when the half‐barrier but not the barrier was present; (d) remembered after the screen was raised whether contact was possible between the cylinder and bug; and (e) were surprised in the no‐contact condition when the bug was launched down the track. A second experiment confirmed the results of Experiment 1. Previous research comparing infants’ responses to no‐contact and contact events has typically made use of self‐moving rather than inert objects. These experiments have consistently found that infants do not look reliably longer at no‐contact than at contact events. In the General Discussion, we examine the contrast between these prior results and the present results and speculate on how infants’ expectations about inert and self‐moving objects may be best characterized.     

Pupillometry reveals communication‐induced object expectations in 12‐ but not 8‐month‐old infants

Several interaction‐based and looking‐time studies suggest that 1‐year‐old infants understand the referential nature of deictic gestures. However, these studies have not unequivocally established that referential gestures induce object expectations in infants prior to encountering a referent object, and have thus remained amenable to simpler attentional highlighting interpretations. The current study tested whether nonlinguistic referential communication induces object expectations in infants by using a novel pupil dilation paradigm. In Experiment 1, 12‐month‐olds watched videos of a protagonist who either pointed communicatively toward an occluder in front of her or remained still. At test, the occluder opened to reveal one of two outcomes: an empty surface or a toy. Results showed that infants’ pupils were larger for the unexpected outcome of an empty surface following a point compared to the control condition (an empty surface following no point). These differences were not caused by differences in looking times or directions. In Experiment 2, an attention‐directing nonsocial control cue replaced the referential communication. The cue did direct 12‐month‐olds’ attention to the occluder, but it did not induce an object expectation. In Experiment 3, we tested 8‐month‐olds in the setting of Experiment 1. In contrast to 12‐month‐olds, 8‐month‐olds did not reveal object expectations following communication. Findings demonstrate that communicative pointing acts induce object expectations at 12 months of age, but not at 8 months of age, and that these expectations are specific to a referential‐communicative as opposed to an attention‐directing nonsocial cue.     

Reasoning about containment events in very young infants

The present research examined very young infants' expectations about containment events. In Experiment 1, 3.5-month-old infants saw a test event in which an object was lowered inside a container with either a wide opening (open-container condition) or no opening (closed-container condition) in its top surface. The infants looked reliably longer at the closed- than at the open-container test event. These and baseline data suggested that the infants recognized that the object could be lowered inside the container with the open but not the closed top. In Experiment 2, 3.5-month-old infants saw a test event in which an object was lowered either behind (behind-container condition) or inside (inside-container condition) a container; next, the container was moved forward and to the side, revealing the object behind it. The infants looked reliably longer at the inside- than at the behind-container test event. These and baseline results suggested that the infants in the inside-container condition realized that the object could not pass through the back wall of the container and hence should have moved with it to its new location. Experiments 3 and 4 extended the results of Experiments 1 and 2 to 2.5-month-old infants. Together, the present results indicate that even very young infants possess expectations about containment events. The possible origins and development of these expectations are discussed in the context of Baillargeon's model (Advances in infancy research 9 (1995) 305. Norwood, NJ: Ablex) of infants' acquisition of physical knowledge, and of Spelke's proposal (Cognition 50 (1994) 431) that, from birth, infants interpret physical events in accord with a solidity principle.     

A perceptual–attentional explanation of gaze following in 3‐ and 6‐month‐olds

Two experiments were conducted with 3‐ and 6‐month‐olds using a standard gaze following procedure with targets to examine the possibility that perceptual–attentional constraints may affect young infants’ gaze following. In Experiment 1, either moving or stationary targets were positioned at 15° from the infants’ midline. In Experiment 2, stationary targets were positioned at either 25° or 40° from the infants’ midline. Gaze following was evaluated with three criteria. Infants made significantly more correct responses to the 15° stationary targets than all other response types combined. When targets were moving or further away, infants made significantly more correct than incorrect responses when they made a turn; however, they did not make significantly more correct responses across all trials. It is argued that the infants’ responses are indicative of perceptual–attention constraints operating where the adult head and eye turn shifts infants’ attention to the side but whether the infants then ‘gaze follow’ depends on the structure of the environment as well as the infants’ ability to disengage attention and initiate saccadic eye movements.     

Seeing behind the surface: communicative demonstration boosts category disambiguation in 12‐month‐olds

In their first years, infants acquire an incredible amount of information regarding the objects present in their environment. While often it is not clear what specific information should be prioritized in encoding from the many characteristics of an object, different types of object representations facilitate different types of generalizations. We tested the hypotheses that 1‐year‐old infants distinctively represent familiar objects as exemplars of their kind, and that ostensive communication plays a role in determining kind membership for ambiguous objects. In the training phase of our experiment, infants were exposed to movies displaying an agent sorting objects from two categories (cups and plates) into two locations (left or right). Afterwards, different groups of infants saw either an ostensive or a non‐ostensive demonstration performed by the agent, revealing that a new object that looked like a plate can be transformed into a cup. A third group of infants experienced no demonstration regarding the new object. During test, infants were presented with the ambiguous object in the plate format, and we measured generalization by coding anticipatory looks to the plate or the cup side. While infants looked equally often towards the two sides when the demonstration was non‐ostensive, and more often to the plate side when there was no demonstration, they performed more anticipatory eye movements to the cup side when the demonstration was ostensive. Thus, ostensive demonstration likely highlighted the hidden dispositional properties of the target object as kind‐relevant, guiding infants’ categorization of the foldable cup as a cup, despite it looking like a plate. These results suggest that infants likely encode familiar objects as exemplars of their kind and that ostensive communication can play a crucial role in disambiguating what kind an object belongs to, even when this requires disregarding salient surface features.     

Fourteen‐month‐old infants track the language comprehension of communicative partners

Infants employ sophisticated mechanisms to acquire their first language, including some that rely on taking the perspective of adults as speakers or listeners. When do infants first show awareness of what other people understand? We tested 14‐month‐old infants in two experiments measuring event‐related potentials. In Experiment 1, we established that infants produce the N400 effect, a brain signature of semantic violations, in a live object naming paradigm in the presence of an adult observer. In Experiment 2, we induced false beliefs about the labeled objects in the adult observer to test whether infants keep track of the other person's comprehension. The results revealed that infants reacted to the semantic incongruity heard by the other as if they encountered it themselves: they exhibited an N400‐like response, even though labels were congruous from their perspective. This finding demonstrates that infants track the linguistic understanding of social partners. A video abstract of this article can be viewed at https://youtu.be/pQUv8yFhnbk .     

Four‐month‐old infants individuate and track simple tools following functional demonstrations

Two experiments examined whether 4‐month‐olds (n = 120) who were induced to assign two objects to different categories would then be able to take advantage of these contrastive categorical encodings to individuate and track the objects. In each experiment, infants first watched functional demonstrations of two tools, a masher and tongs (Experiment 1) or a marker and a knife (Experiment 2). Next, half the infants saw the two tools brought out alternately from behind a screen, which was then lowered to reveal only one of the tools (different‐objects condition); the other infants saw similar events except that the same tool was shown on either side of the screen (same‐object condition). In both experiments, infants in the different‐objects condition looked reliably longer than those in the same‐object condition, and this effect was eliminated if the demonstrations involved similar but non‐functional actions. Together, these results indicate that infants (a) were led by the functional demonstrations they observed to assign the two tools to distinct categories, (b) recruited these categorical encodings to individuate and track the tools, and hence (c) detected a violation in the different‐objects condition when the screen was lowered to reveal only one tool. Categorical information thus plays a privileged role in individuation and identity tracking from a very young age.     

Inferring the size of a goal object from an actor's grasping movement in 6‐ and 9‐month‐old infants

The present study applied a preferential looking paradigm to test whether 6‐ and 9‐month old infants are able to infer the size of a goal object from an actor's grasping movement. The target object was a cup with the handle rotated either towards or away from the actor. In two experiments, infants saw the video of an actor's grasping movement towards an occluded target object. The aperture size of the actor's hand was varied as between‐subjects factor. Subsequently, two final states of the grasping movement were presented simultaneously with the occluder being removed. In Experiment 1, the expected final state showed the actor's hand holding a cup in a way that would be expected after the performed grasping movement. In the unexpected final state, the actor's hand held the cup at the side which would be unexpected after the performed grasping movement. Results show that 6‐ as well as 9‐month‐olds looked longer at the unexpected than at the expected final state. Experiment 2 excluded an alternative explanation of these findings, namely that the discrimination of the final states was due to geometrical familiarity or novelty of the final states. These findings provide evidence that infants are able to infer the size of a goal object from the aperture size of the actor's hand during the grasp.     

Nine‐ to 11‐month‐old infants' reasoning about causality in anomalous human movements1

Two habituation experiments investigated 9–11‐month‐old infants' reasoning about causality in anomalous human movements. During habituation, infants saw an event in which a person walked toward a stationary person behind an occluder who fell down after an interval. Then, the infants were tested with two events without the occluder: the contact event in which the first person pushed the second one to fall down and the no‐contact event in which the second person fell down without any contact. In Experiment 1, in which the persons were face‐to‐back, infants looked at the no‐contact event for a longer time, whereas in Experiment 2, in which the persons were face‐to‐face, they looked at both the events for equal duration. Thus, infants considered it unnatural when a person fell down without external force in the absence of any action from a distance (e.g. communication). Infants seem to apply the physical contact principles to human movements in certain cases.     

Occluding the trajectory of an object: effects on predicting containment with 9-, 12- and 16-month-olds

Infants of 9-16-month-old repeatedly saw a block that was lowered into the opening of a container. It was found that the more time infants have to see the block relative to the container the easier they detect that the object relation specifies containment.     

The effects of adults' affective expression and direction of visual gaze on 12‐month‐olds' visual preferences for an object following a 5‐minute, 1‐day,or 1‐month delay

Between 12‐ and 14 months of age infants begin to use another's direction of gaze and affective expression in learning about various objects and events. What is not well understood is how long infants' behaviour towards a previously unfamiliar object continues to be influenced following their participation in circumstances of social referencing. In this experiment, we examined infants' sensitivity to an adult's direction of gaze and their visual preference for one of two objects following a 5‐min, 1‐day, or 1‐month delay. Ninety‐six 12‐month‐olds participated. For half of the infants during habituation (i.e., familiarization), the adults' direction of gaze was directed towards an unfamiliar object (look condition). For the remaining half of the infants during habituation, the adults' direction of gaze was directed away from the unfamiliar object (look‐away condition). All infants were habituated to two events. One event consisted of an adult looking towards (look condition) or away from (look‐away condition) an object while facially and vocally conveying a positive affective expression. The second event consisted of the same adult looking towards or away from a different object while conveying a disgusted affective expression. Following the habituation phase and a 5‐min, 1‐day, or 1‐month delay, infants' visual preference was assessed. During the visual preference phase, infants saw the two objects side by side where the adult conveying the affective expression was not visible. Results of the visual preference phase indicate that infants in the look condition showed a significant preference for object previously paired with the positive affect following a 5‐min and 1‐day delay. No significant visual preference was found in the look condition following a 1‐month delay. No significant preferences were found at any retention interval in the look‐away condition. Results are discussed in terms of early learning, social referencing, and early memory.     

The movement of internal facial features elicits 7 to 8‐month‐old infants' preference for face patterns

A preference for static face patterns is observed in newborns and disappears around 3 months after birth. A previous study has demonstrated that 5‐month‐old infants prefer schematic faces only when the internal features are moving, suggesting that face‐specific movement enhances infants' preference. The present study investigates the facilitative effect of the movement of internal facial features on infants' preference. To examine infants' preference, we used animated face patterns consisting of a head‐shaped contour and three disk blobs. The inner blobs expanded and contracted to represent the opening and closing of the eyes and mouth, and were constrained to open and close only in a biologically possible vertical direction resembling the facial muscle structure. We compared infants' preferential looking time for this vertically moving (VM) face pattern with their looking time for a horizontally moving (HM) face pattern in which blobs transformed at the same speed in a biologically impossible, horizontal direction. In Experiment 1, 7 to 8‐month‐olds preferred the VM to the HM, but 5 to 6‐month‐olds did not. However, the preference was diminished in both cases when the moving face patterns were presented without contour (Experiment 2). Our results suggest that internal facial features with vertical movements promote face preference in 7 to 8‐month‐olds. Copyright © 2011 John Wiley & Sons, Ltd.     

On the Counterfactual Nature of Gambling Near‐misses: An Experimental Study

Research on gambling near‐misses has shown that objectively equivalent outcomes can yield divergent emotional and motivational responses. The subjective processing of gambling outcomes is affected substantially by close but non‐obtained outcomes (i.e. counterfactuals). In the current paper, we investigate how different types of near‐misses influence self‐perceived luck and subsequent betting behavior in a wheel‐of‐fortune task. We investigate the counterfactual mechanism of these effects by testing the relationship with a second task measuring regret/relief processing. Across two experiments (Experiment 1, n = 51; Experiment 2, n = 104), we demonstrate that near‐wins (neutral outcomes that are close to a jackpot) decreased self‐perceived luck, whereas near‐losses (neutral outcomes that are close to a major penalty) increased luck ratings. The effects of near‐misses varied by near‐miss position (i.e. whether the spinner stopped just short of, or passed through, the counterfactual outcome), consistent with established distinctions between upward versus downward, and additive versus subtractive, counterfactual thinking. In Experiment 1, individuals who showed stronger counterfactual processing on the regret/relief task were more responsive to near‐wins and near‐losses on the wheel‐of‐fortune task. The effect of near‐miss position was attenuated when the anticipatory phase (i.e. the spin and deceleration) was removed in Experiment 2. Further differences were observed within the objective gains and losses, between “clear” and “narrow” outcomes. Taken together, these results help substantiate the counterfactual mechanism of near‐misses. © 2017 The Authors Journal of Behavioral Decision Making Published by John Wiley & Sons Ltd.     

Active vision in passive locomotion: real‐world free viewing in infants and adults

Visual exploration in infants and adults has been studied using two very different paradigms: free viewing of flat screen displays in desk‐mounted eye‐tracking studies and real‐world visual guidance of action in head‐mounted eye‐tracking studies. To test whether classic findings from screen‐based studies generalize to real‐world visual exploration and to compare natural visual exploration in infants and adults, we tested observers in a new paradigm that combines critical aspects of both previous techniques: free viewing during real‐world visual exploration. Mothers and their 9‐month‐old infants wore head‐mounted eye trackers while mothers carried their infants in a forward‐facing infant carrier through a series of indoor hallways. Demands for visual guidance of action were minimal in mothers and absent for infants, so both engaged in free viewing while moving through the environment. Similar to screen‐based studies, during free viewing in the real world low‐level saliency was related to gaze direction. In contrast to screen‐based studies, only infants – not adults – were biased to look at people, participants of both ages did not show a classic center bias, and mothers and infants did not display high levels of inter‐observer consistency. Results indicate that several aspects of visual exploration of a flat screen display do not generalize to visual exploration in the real world.     

Effects of balance relations between objects on infant’s object segregation

Young infants are sensitive to support relations between objects. However, the types of contact perceived to be sufficient for object support change over development. At 4.5 months of age, infants expect an object to be adequately supported when in contact with another object. By 6.5 months, this simple contact/no‐contact distinction is refined to account for proportion of contact: an object is perceived to be supported when 70% of its bottom surface is in contact with another object, but it is not perceived to be supported when 15% is contacted. Here, we employ an object segregation paradigm to investigate whether 8‐month‐old infants’ judgments of support relations are mediated by assessments both of the proportion of contact and of the position of contact. Infants in the current experiments viewed test displays consisting of two objects, a long thin object (a box) and a smaller roughly cubic object (a box in Experiment 1, a cylinder in Experiments 2 and 3). Two basic positions of contact were used, such that either the centers or the lateral edges of the two objects were aligned. The proportion of contact was manipulated across experiments by having the smaller object support the larger or the larger object support the smaller. There was a significant effect of position of contact when only a small proportion of the upper object was contacted by the lower object. However, position of contact was found not to matter when all of the upper object was in contact with the lower object. We conclude that 8‐month‐old infants’ judgments of support relations are influenced by both proportion and position of supporting contact. We integrate the findings from the current experiments into the general developmental framework proposed by Baillargeon and colleagues.     

Executive functioning by 18‐24‐month‐old children: effects of inhibition,working memory demands and narrative in a novel detour‐reaching task

Infants can inhibit a prepotent but wrong action towards a goal in order to perform a causal means‐action. It is not clear, however, whether infants can perform an arbitrary means‐action while inhibiting a prepotent response. In four experiments, we explore this executive functioning in 18–24‐month‐old children. The working memory and inhibition demands in a novel means‐end problem were systematically varied in terms of the type and combination of means‐action(s) (causal or arbitrary) contained within the task, the number of means‐actions (1 or 2), the goal visual availability and whether the task was accompanied by a narrative. Experiments 1 and 2 showed that children performed tasks that contained causal as opposed to arbitrary information more accurately; accuracy was also higher in tasks containing only one step. Experiment 2 also demonstrated that performance in the arbitrary task improved significantly when all sources of prepotency were removed. In Experiment 3, task performance improved when the two means‐actions were intelligibly linked to the task goal. Experiment 4 demonstrated that the use of a narrative that provided a meaningful (non‐causal) link between the two means‐actions also improved children's performance by assisting their working memory in the generation of a rationale. Findings provide an initial account of executive functioning in the months that bring the end of infancy. Copyright © 2006 John Wiley & Sons, Ltd.     

Information from multiple modalities helps 5‐month‐olds learn abstract rules

By 7 months of age, infants are able to learn rules based on the abstract relationships between stimuli ( Marcus et al ., 1999 ), but they are better able to do so when exposed to speech than to some other classes of stimuli. In the current experiments we ask whether multimodal stimulus information will aid younger infants in identifying abstract rules. We habituated 5‐month‐olds to simple abstract patterns (ABA or ABB) instantiated in coordinated looming visual shapes and speech sounds (Experiment 1), shapes alone (Experiment 2), and speech sounds accompanied by uninformative but coordinated shapes (Experiment 3). Infants showed evidence of rule learning only in the presence of the informative multimodal cues. We hypothesize that the additional evidence present in these multimodal displays was responsible for the success of younger infants in learning rules, congruent with both a Bayesian account and with the Intersensory Redundancy Hypothesis.     

Development of chromatic induction in infancy

The perception of colour in an embedded field is affected by the surround colour. This phenomenon is known as chromatic induction. In the present study we investigated whether the colour perception by infants aged 5–7 months could be affected by the surround colour. In Experiments 1 and 2 each stimulus was composed of an array of six squares in tandem. The colour appearance of the array in the familiarization stimulus was established by chromatic induction. In Experiment 1 we used familiarization stimuli that were perceived as two‐colour array with a two‐colour surround. In Experiment 2 we used a familiarization stimulus that was perceived as a uniform‐colour array with a two‐colour surround. In the test phase, the uniform‐colour array and the two‐colour array were presented on a white uniform‐colour surround in both experiments. The results showed that in Experiment 1 the 5‐ and 7‐month‐old infants had novelty preference for the uniform‐colour test array. This suggested that the infants' colour perception could be affected by surround colour. The results of Experiment 2 showed that the 7‐month‐olds showed a novelty preference for the two‐colour test array, but the 5‐month‐olds showed no novelty preference. This suggested that 7‐month‐olds' colour perception could be affected by surround colour, but that of 5‐month‐olds could not. We discuss the contradiction of the results between Experiments 1 and 2. Copyright © 2007 John Wiley & Sons, Ltd.