Playing hide and seek: Contextual regularity learning develops between 3 and 5 years of age.

The ability to acquire contextual regularities is fundamental in everyday life because it helps us to navigate the environment, directing our attention where relevant events are more likely to occur. Sensitivity to spatial regularities has been largely reported from infancy. Nevertheless, it is currently unclear when children can use this rapidly acquired contextual knowledge to guide their behavior. Evidence of this ability is indeed mixed in school-aged children and, to date, it has never been explored in younger children and toddlers. The current study investigated the development of contextual regularity learning in children aged 3 to 5 years. To this aim, we designed a new contextual learning paradigm in which young children were presented with recurring configurations of bushes and were asked to guess behind which bush a cartoon monkey was hiding. In a series of two experiments, we manipulated the relevance of color and visuospatial cues for the underlying task goal and tested how this affected young children's behavior. Our results bridge the gap between the infant and adult literatures, showing that sensitivity to spatial configurations persists from infancy to childhood, but it is only around the fifth year of life that children naturally start to integrate multiple cues to guide their behavior.

Neural and Cognitive Underpinnings of Counterintuitive Science and Math Reasoning in Adolescence.

Reasoning about counterintuitive concepts in science and math is thought to require suppressing naive theories, prior knowledge, or misleading perceptual cues through inhibitory control. Neuroimaging research has shown recruitment of pFC regions during counterintuitive reasoning, which has been interpreted as evidence of inhibitory control processes. However, the results are inconsistent across studies and have not been directly compared with behavior or brain activity during inhibitory control tasks. In this fMRI study, 34 adolescents (aged 11-15 years) answered science and math problems and completed response inhibition tasks (simple and complex go/no-go) and an interference control task (numerical Stroop). Increased BOLD signal was observed in parietal (Brodmann's area 40) and prefrontal (Brodmann's area 8, 45/47) cortex regions in counterintuitive problems compared with control problems, where no counterintuitive reasoning was required, and in two parietal clusters when comparing correct counterintuitive reasoning to giving the incorrect intuitive response. There was partial overlap between increases in BOLD signal in the complex response inhibition and interference control tasks and the science and math contrasts. However, multivariate analyses suggested overlapping neural substrates in the parietal cortex only, in regions typically associated with working memory and visuospatial attentional demands rather than specific to inhibitory control. These results highlight the importance of using localizer tasks and a range of analytic approach to investigate to what extent common neural networks underlie performance of different cognitive tasks and suggests visuospatial attentional skills may support counterintuitive reasoning in science and math.

Remembering nothing: Encoding and memory processes involved in representing empty locations.

Previous research has provided rich evidence that a set of visual objects can be encoded in isolation along with their exact coordinate positions as well as a global configuration that provides a network of interrelated spatial information. However, much less data is available on how unoccupied locations are encoded and maintained in memory. We tested this ability in adults using a novel paradigm that involved both empty and filled locations and required participants to monitor the addition or deletion of an item, which occurred 50% of the time. Crucially, a number of locations remained hidden to the participant-thus, information on the absence of an item at a location could not be inferred from the presence of items elsewhere. We used eye-tracking to measure the proportion of target looking during encoding and the amount of pupil dilation during memory retention. Participants looked significantly longer at filled compared with empty targets, and target looking during encoding only predicted accuracy in case of filled targets. Increased pupil dilation was observed in response to an increasing number of items, while pupil diameter was unaffected by the number of empty locations. In addition, participants made significantly more errors in the conditions that involved the representation of an empty location. Our findings support the view that human adults encode exact coordinates of items in memory. In contrast, we suggest that empty locations are represented as a property of the global configuration of items and empty space, and not as independent units of information.

Oxytocin but not naturally occurring variation in caregiver touch associates with infant social orienting.

Caregiver touch is crucial for infants' healthy development, but its role in shaping infant cognition has been relatively understudied. In particular, despite strong premises to hypothesize its function in directing infant attention to social information, little empirical evidence exists on the topic. In this study, we investigated the associations between naturally occurring variation in caregiver touch and infant social attention in a group of 6- to 13-month-old infants (n = 71). Additionally, we measured infant salivary oxytocin as a possible mediator of the effects of touch on infant social attention. The hypothesized effects were investigated both short term, with respect to touch observed during parent-infant interactions in the lab, and long term, with respect to parent-reported patterns of everyday touching behaviors. We did not find evidence that caregiver touch predicts infant social attention or salivary oxytocin levels, short term or long term. However, we found that salivary oxytocin predicted infant preferential attention to faces relative to nonsocial objects, measured in an eye-tracking task. Our findings confirm the involvement of oxytocin in social orienting in infancy, but raise questions regarding the possible environmental factors influencing the infant oxytocin system.

Left, right, left, right: 24-36-months-olds' planning and execution of simple alternating actions.

This study investigated toddlers' ability to control simple alternating pattern actions, and how this relates to motor competence and executive functions. 70 toddlers between 24 and 36 months of age were instructed to sort coins in an alternating pattern into two boxes; left, right, left, right etc. Executive functions and memory competence performance were assessed in additional small games. The results showed that the ability to plan and execute actions according to a simple extended alternating pattern improved over toddlerhood. Furthermore, working memory and motor competence scores were both independent predictors of the ability to plan and execute simple alternating actions. These findings underscore the fact that between 24 and 36 months of age is a period in which the ability to string together multiple actions in a sequence to achieve a distal goal is still developing.

Infant Spontaneous Motor Tempo.

Spontaneous Motor Tempo (SMT) is influenced by individual differences in age and body size. We present the first data documenting the SMT of infants from 5 to 37 months of age using a simple drumming task. As in late childhood and adulthood, we predicted that infant SMT would slow across the first years of life. However, we find that older infants drum more quickly than younger infants. Furthermore, studies of adults suggest larger bodies prefer slower rhythms. This relationship may be the product of biomechanical resonance, or effects may be driven by rhythmic experience, such as of locomotion. We used infants, whose body size is dissociated from their predominant experience of locomotion as their parent often carries them, to test this argument. We reveal that infant SMT is predicted by parent, but not own, body size, supporting a passive experience-based argument, and propose that early rhythm may be set by repetitive vestibular stimulation when carried by the caregiver.

Science with Duplo: Multilevel goal management in preschoolers' toy house constructions.

Executing goal-directed action sequences is fundamental to our behavior. Planning and controlling these action sequences improves greatly over the preschool years. In this study, we examined preschoolers' ability to plan action sequences. A total of 69 3- to 5-year-olds were assessed on an action sequence planning task with a hierarchical goal structure and on several executive function tasks. Planning abilities improved with age. Improvements in inhibition were related to avoidance of actions irrelevant to the goal hierarchy. Updating skill appears to be associated with executing actions relevant to different subgoals. Using optical motion capture, we showed that children who followed the subgoals displayed less movement with their nonreaching hand within a subgoal. This effect was enhanced in children with better inhibitory skills, suggesting that such skills allow greater focus on executing the current subgoal. Thus, we provide evidence that structuring of subgoals in action sequence planning emerges during the preschool years and that improvements in performance in action sequence planning are related to executive functions.

Does surprise enhance infant memory? Assessing the impact of the encoding context on subsequent object recognition.

A discrepancy between what was predicted and what is observed has been linked to increased looking times, changes in brain electrical activity, and increased pupil dilation in infants. These processes associated with heightened attention and readiness to learn might enhance the encoding and memory consolidation of the surprising object, as suggested by both the infant and the adult literature. We therefore investigated whether the presence of surprise during the encoding context enhances subsequent encoding and recognition memory processes for the items that violated infants' expectations. Seventeen-month-olds viewed 20 familiar objects, half of which were labeled correctly, while the other half were mislabeled. Subsequently, infants were presented with a silent recognition memory test where the previously labeled objects appeared along with new images. Pupil dilation was measured, with more dilated pupils indicating (1) surprise during those labeling events where the item was mislabeled and (2) successful retrieval processes during the memory test. Infants responded with more pupil dilation to mislabeling compared to correct labeling. Importantly, despite the presence of a surprise response during mislabeling, infants only differentiated between the previously seen and unseen items at the memory test, offering no evidence that surprise had facilitated the encoding of the mislabeled items.

Capturing touch in parent-infant interaction: A comparison of methods.

Naturally occurring high levels of caregiver touch promote offspring development in many animal species. Yet, caregiver touch remains a relatively understudied topic in human development, possibly due to challenges of measuring this means of interaction. While parental reports (e.g., questionnaires, diaries) are easy to collect, they may be subject to biases and memory limitations. In contrast, observing touch in a short session of parent-child interaction in the lab may not be representative of touch interaction in daily life. In the present study, we compared parent reports (one-off questionnaires and diary) and observation-based methods in a sample of German 6- to 13-month-olds and their primary caregivers (n = 71). In an attempt to characterize touching behaviors across a broad range of contexts, we measured touch both during play and while the parent was engaged in another activity. We found that context affected both the quantity and types of touch used in interaction. Parent-reported touch was moderately associated with touch observed in parent-child interactions and more strongly with touch used during play. We conclude that brief one-off questionnaires are a good indicator of touch in parent-child interaction, yet they may be biased toward representing particular daily activities and particular types of touch.

Withstanding the test of time: Multisensory cues improve the delayed retention of incidental learning.

Multisensory tools are commonly employed within educational settings (e.g. Carter & Stephenson, ), and there is a growing body of literature advocating the benefits of presenting children with multisensory information over unisensory cues for learning (Baker & Jordan, ; Jordan & Baker, ). This is even the case when the informative cues are only arbitrarily related (Broadbent, White, Mareschal, & Kirkham, ). However, the delayed retention of learning following exposure to multisensory compared to unisensory cues has not been evaluated, and has important implications for the utility of multisensory educational tools. This study examined the retention of incidental categorical learning in 5-, 7- and 9-year-olds (N = 181) using either unisensory or multisensory cues. Results found significantly greater retention of learning following multisensory cue exposure than with unisensory information when category knowledge was tested following a 24-hour period of delay. No age-related changes were found, suggesting that multisensory information can facilitate the retention of learning across this age range.

Incidental learning in a multisensory environment across childhood.

Multisensory information has been shown to modulate attention in infants and facilitate learning in adults, by enhancing the amodal properties of a stimulus. However, it remains unclear whether this translates to learning in a multisensory environment across middle childhood, and particularly in the case of incidental learning. One hundred and eighty-one children aged between 6 and 10 years participated in this study using a novel Multisensory Attention Learning Task (MALT). Participants were asked to respond to the presence of a target stimulus whilst ignoring distractors. Correct target selection resulted in the movement of the target exemplar to either the upper left or right screen quadrant, according to category membership. Category membership was defined either by visual-only, auditory-only or multisensory information. As early as 6 years of age, children demonstrated greater performance on the incidental categorization task following exposure to multisensory audiovisual cues compared to unisensory information. These findings provide important insight into the use of multisensory information in learning, and particularly on incidental category learning. Implications for the deployment of multisensory learning tasks within education across development will be discussed.

Task switching costs in preschool children and adults.

Past research investigating cognitive flexibility has shown that preschool children make many perseverative errors in tasks that require switching between different sets of rules. However, this inflexibility might not necessarily hold with easier tasks. The current study investigated the developmental differences in cognitive flexibility using a task-switching procedure that compared reaction times and accuracy in 4- and 6-year-olds with those in adults. The experiment involved simple target detection tasks and was intentionally designed in a way that the stimulus and response conflicts were minimal together with a long preparation window. Global mixing costs (performance costs when multiple tasks are relevant in a context), and local switch costs (performance costs due to switching to an alternative task) are typically thought to engage endogenous control processes. If this is the case, we should observe developmental differences with both of these costs. Our results show, however, that when the accuracy was good, there were no age differences in cognitive flexibility (i.e., the ability to manage multiple tasks and to switch between tasks) between children and adults. Even though preschool children had slower reaction times and were less accurate, the mixing and switch costs associated with task switching were not reliably larger for preschool children. Preschool children did, however, show more commission errors and greater response repetition effects than adults, which may reflect differences in inhibitory control.

Embodiment and the origin of interval timing: kinematic and electromyographic data.

Recent evidence suggests that interval timing (the judgment of durations lasting from approximately 500 ms. to a few minutes) is closely coupled to the action control system. We used surface electromyography (EMG) and motion capture technology to explore the emergence of this coupling in 4-, 6-, and 8-month-olds. We engaged infants in an active and socially relevant arm-raising task with seven cycles and response period. In one condition, cycles were slow (every 4 s); in another, they were fast (every 2 s). In the slow condition, we found evidence of time-locked sub-threshold EMG activity even in the absence of any observed overt motor responses at all three ages. This study shows that EMGs can be a more sensitive measure of interval timing in early development than overt behavior.

Preschool children's control of action outcomes.

Naturalistic goal-directed behaviours require the engagement and maintenance of appropriate levels of cognitive control over relatively extended intervals of time. In two experiments, we examined preschool children's abilities to maintain top-down control throughout the course of a sequential task. Both 3- and 5-year-olds demonstrated good abilities to access goals at the lowest level of the representational hierarchy. However, only 5-year-olds consistently aligned their response choices with goals at superordinate levels. These findings suggest that the ability to maintain top-down control and adjust behavioural responses according to goals at multiple levels of abstraction undergoes a marked improvement throughout the preschool period. Results are discussed in relation to current accounts of cognitive control and the monitoring of conflict in sequential action.

The impact of semantically congruent and incongruent visual information on auditory object recognition across development.

The ability to use different sensory signals in conjunction confers numerous advantages on perception. Multisensory perception in adults is influenced by factors beyond low-level stimulus properties such as semantic congruency. Sensitivity to semantic relations has been shown to emerge early in development; however, less is known about whether implementation of these associations changes with development or whether development in the representations themselves might modulate their influence. Here, we used a Stroop-like paradigm that requires participants to identify an auditory stimulus while ignoring a visual stimulus. Prior research shows that in adults visual distractors have more impact on processing of auditory objects than vice versa; however, this pattern appears to be inverted early in development. We found that children from 8years of age (and adults) gain a speed advantage from semantically congruent visual information and are disadvantaged by semantically incongruent visual information. At 6years of age, children gain a speed advantage for semantically congruent visual information but are not disadvantaged by semantically incongruent visual information (as compared with semantically unrelated visual information). Both children and adults were influenced by associations between auditory and visual stimuli, which they had been exposed to on only 12 occasions during the learning phase of the study. Adults showed a significant speed advantage over children for well-established associations but showed no such advantage for newly acquired pairings. This suggests that the influence of semantic associations on multisensory processing does not change with age but rather these associations become more robust and, in turn, more influential.

Integration of audio-visual information for spatial decisions in children and adults.

In adults, decisions based on multisensory information can be faster and/or more accurate than those relying on a single sense. However, this finding varies significantly across development. Here we studied speeded responding to audio-visual targets, a key multisensory function whose development remains unclear. We found that when judging the locations of targets, children aged 4 to 12 years and adults had faster and less variable response times given auditory and visual information together compared with either alone. Comparison of response time distributions with model predictions indicated that children at all ages were integrating (pooling) sensory information to make decisions but that both the overall speed and the efficiency of sensory integration improved with age. The evidence for pooling comes from comparison with the predictions of Miller's seminal 'race model', as well as with a major recent extension of this model and a comparable 'pooling' (coactivation) model. The findings and analyses can reconcile results from previous audio-visual studies, in which infants showed speed gains exceeding race model predictions in a spatial orienting task (Neil et al., 2006) but children below 7 years did not in speeded reaction time tasks (e.g. Barutchu et al., 2009). Our results provide new evidence for early and sustained abilities to integrate visual and auditory signals for spatial localization from a young age.

Infants' selective attention to reliable visual cues in the presence of salient distractors.

With many features competing for attention in their visual environment, infants must learn to deploy attention toward informative cues while ignoring distractions. Three eye tracking experiments were conducted to investigate whether 6- and 8-month-olds (total N = 102) would shift attention away from a distractor stimulus to learn a cue-reward relation. While 8-month-olds showed evidence of increasingly selective attention toward the predictive cues, even when the distractors were highly salient, 6-month-olds shifted attention toward the predictive cues only when the distractors were equally (not more) engaging. These experiments suggest that attention in infancy is highly dependent on the relative weightings of predictiveness and visual salience, which may differ across development and context.

Local redundancy governs infants' spontaneous orienting to visual-temporal sequences.

Two experiments demonstrate that 5-month-olds are sensitive to local redundancy in visual-temporal sequences. In Experiment 1, 20 infants saw 2 separate sequences of looming colored shapes that possessed the same elements but contrasting transitional probabilities. One sequence was random whereas the other was based on bigrams. Without any prior exposure, infants looked longer at the random sequence. In Experiment 2, 17 infants looked equally long at bigram- and trigram-based sequences. However, an analysis of local redundancy revealed that in both experiments disengagement from the sequences was governed by local repetitions rather than by global sequence statistics. This finding suggests that a spontaneous sensitivity to stimulus complexity helps orient infants to sequences they can learn from.

Fusion of visual cues is not mandatory in children.

Human adults can go beyond the limits of individual sensory systems' resolutions by integrating multiple estimates (e.g., vision and touch) to reduce uncertainty. Little is known about how this ability develops. Although some multisensory abilities are present from early infancy, it is not until age ≥8 y that children use multiple modalities to reduce sensory uncertainty. Here we show that uncertainty reduction by sensory integration does not emerge until 12 y even within the single modality of vision, in judgments of surface slant based on stereoscopic and texture information. However, adults' integration of sensory information comes at a cost of losing access to the individual estimates that feed into the integrated percept ("sensory fusion"). By contrast, 6-y-olds do not experience fusion, but are able to keep stereo and texture information separate. This ability enables them to outperform adults when discriminating stimuli in which these information sources conflict. Further, unlike adults, 6-y-olds show speed gains consistent with following the fastest-available single cue. Therefore, whereas the mature visual system is optimized for reducing sensory uncertainty, the developing visual system may be optimized for speed and for detecting sensory conflicts. Such conflicts could provide the error signals needed to learn the relationships between sensory information sources and to recalibrate them while the body is growing.

Assessing executive functions in free-roaming 2- to 3-year-olds.

Introduction: Core aspects of executive functions (EFs) are known to be related to academic skills such as literacy and numeracy. However, school outcomes may also be related to higher-level functions such as planning. Nevertheless, few studies have considered assessing natural manifestations of higher-level EFs in children who are on the cusp of entering formal schooling. One reason for this is the difficulty of obtaining ecologically valid measures of EFs in preschool-aged children. Method: We describe a novel task - building a striped Duplo tower subject to two constraints - designed to assess planning in real-world multi-action situation. Children were instructed to build a tower to a certain height by alternating between two different colors of blocks. Results: Performance on one of the constraints in this task was found to vary with age. Importantly, distinct components of multiple constraints planning performance predicted laboratory-based measures of inhibitory control and working memory efficacy. Discussion: Thus, this task provides a simple, cheap and effective way of assessing executive function in toddlers through the observation of natural behavior. It also opens up possibilities to investigate the neurodevelopment of EF in the real world.