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AbstractMany everyday actions are implicit gambles because imprecisions in our visuomotor systems place probabilities on our success or failure. Choosing optimal action strategies involves weighting the costs and gains of potential outcomes by their corresponding probabilities, and requires stable representations of one's own imprecisions. How this ability is acquired during development in childhood when visuomotor skills change drastically is unknown. In a rewarded rapid reaching task, 6‐ to 11‐year‐old children followed 'risk‐seeking' strategies leading to overly high point‐loss. Adults' performance, in contrast, was close to optimal. Children's errors were not explained by distorted estimates of value or probability, but may reflect different action selection criteria or immature integration of value and probability information while planning movements. These findings provide a starting point for understanding children's risk‐taking in everyday visuomotor situations when suboptimal choices can be dangerous. Moreover, children's risky visuomotor decisions mirror those reported for non‐motor gambles, raising the possibility that common processes underlie development across decision‐making domains.

AbstractIn 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 (Neilet al., 2006) but children below 7 years did not in speeded reaction time tasks (e.g. Barutchuet 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.

AbstractWhen visual information is available, human adults, but not children, have been shown to reduce sensory uncertainty by taking a weighted average of sensory cues. In the absence of reliable visual information (e.g. extremely dark environment, visual disorders), the use of other information is vital. Here we ask how humans combine haptic and auditory information from childhood. In the first experiment, adults and children aged 5 to 11 years judged the relative sizes of two objects in auditory, haptic, and non‐conflicting bimodal conditions. In , different groups of adults and children were tested in non‐conflicting and conflicting bimodal conditions. In , adults reduced sensory uncertainty by integrating the cues optimally, while children did not. In , adults and children used similar weighting strategies to solve audio–haptic conflict. These results suggest that, in the absence of visual information, optimal integration of cues for discrimination of object size develops late in childhood.

Abstract Williams syndrome (WS) is a genetic disorder associated with severe visuocognitive impairment. Individuals with WS also report difficulties with everyday wayfinding. To study the development of body‐, environment‐, and object‐based spatial frames of reference in WS, we tested 45 children and adults with WS on a search task in which the participant and a spatial array are moved with respect to each other. Although individuals with WS showed a marked delay, like young controls they demonstrated independent, additive use of body‐ and environment‐based frames of reference. Crucially, object‐based (intrinsic) representations based on local landmarks within the array were only marginally used even by adults with WS, whereas in typical development these emerge at 5 years. Deficits in landmark use are consistent with wayfinding difficulties in WS, and may also contribute to problems with basic localization, since in typical development landmark‐based representations supplement those based on the body and on self‐motion. Difficulties with inhibition or mental rotation may be further components in the impaired ability to use the correct reference frame in WS.

AbstractUsing landmarks and other scene features to recall locations from new viewpoints is a critical skill in spatial cognition. In an immersive virtual reality task, we asked children 3.5–4.5 years old to remember the location of a target using various cues. On some trials they could use information from their own self‐motion. On some trials they could use a view match. In the very hardest kind of trial, they were 'teleported' to a new viewpoint and could only use an allocentric spatial representation. This approach provides a strict test for allocentric coding (without either a matching viewpoint or self‐motion information) while avoiding additional task demands in previous studies (it does not require them to deal with a small table‐top environment or to manage stronger cue conflicts). Both the younger and older groups were able to point back at the target location better than chance when they could use view matching and/or self‐motion, but allocentric recall was only seen in the older group (4.0–4.5). In addition, we only obtained evidence for a specific kind of allocentric recall in the older group: they tracked one major axis of the space significantly above chance, r(158) = .28, but not the other, r(158) = −.01. We conclude that there is a major qualitative change in coding for spatial recall around the fourth birthday, potentially followed by further development towards fully flexible recall from new viewpoints.

AbstractIt has been suggested that learning an object's location relative to (1) intramaze landmarks and (2) local boundaries is supported by parallel striatal and hippocampal systems, both of which rely upon input from a third system for orientation. However, little is known about the developmental trajectories of these systems' contributions to spatial learning. The present study tested 5‐ and 7‐year‐old children and adults on a water maze‐like task in which all three types of cue were available. Participants had to remember the location of an object hidden in a circular bounded environment containing a moveable intramaze landmark and surrounded by distal cues. Children performed less accurately than adults, and showed a different pattern of error. While adults relied most on the stable cue provided by the boundary, children relied on both landmark and boundary cues similarly, suggesting a developmental increase in the weighting given to boundary cues. Further, adults were most accurate in coding angular information (dependent on distal cues), whereas children were most accurate in coding distance, suggesting a developing ability to use distal cues to orient. These results indicate that children as young as 5 years use boundary, intramaze landmark, and distal visual cues in parallel, but that the basic accuracy and relative weighting of these cues changes during subsequent development.

AbstractWhen the illumination falling on a surface change, so does the reflected light. Despite this, adult observers are good at perceiving surfaces as relatively unchanging—an ability termed colour constancy. Very few studies have investigated colour constancy in infants, and even fewer in children. Here we asked whether there is a difference in colour constancy between children and adults; what the developmental trajectory is between six and 11 years; and whether the pattern of constancy across illuminations and reflectances differs between adults and children. To this end, we developed a novel, child‐friendly computer‐based object selection task. In this, observers saw a dragon's favourite sweet under a neutral illumination and picked the matching sweet from an array of eight seen under a different illumination (blue, yellow, red, or green). This set contained a reflectance match (colour constant; perfect performance) and a tristimulus match (colour inconstant). We ran two experiments, with two‐dimensional scenes in one and three‐dimensional renderings in the other. Twenty‐six adults and 33 children took part in the first experiment; 26 adults and 40 children took part in the second. Children performed better than adults on this task, and their performance decreased with age in both experiments. We found differences across illuminations and sweets, but a similar pattern across both age groups. This unexpected finding might reflect a real decrease in colour constancy from childhood to adulthood, explained by developmental changes in the perceptual and cognitive mechanisms underpinning colour constancy, or differences in task strategies between children and adults.Highlights
Six‐ to 11‐year‐old children demonstrated better performance than adults on a colour constancy object selection task.
Performance decreased with age over childhood.
These findings may indicate development of cognitive strategies used to overcome automatic colour constancy mechanisms.