The first year in formal schooling improves working memory and academic abilities.

Neurocognition and academic abilities during the period of 4 and 7 years of age are impacted by both the transition from kindergarten to primary school and age-related developmental processes. Here, we used a school cut-off design to tease apart the impact of formal schooling from age, on working memory (WM) function, vocabulary, and numeracy scores. We compared two groups of children with similar age, across two years: first-graders (FG), who were enrolled into primary school the year that they became eligible and kindergarteners (KG), who were deferred school entry until the following year. All children completed a change detection task while brain activation was recorded using portable functional near-infrared spectroscopy, a vocabulary assessment, and a numeracy screener. Our results revealed that FG children showed greater improvement in WM performance and greater engagement of a left-lateralized fronto-parietal network compared to KG children. Further, they also showed higher gains in vocabulary and non-symbolic numeracy scores. This improvement in vocabulary and non-symbolic numeracy scores following a year in primary school was predicted by WM function. Our findings contribute to a growing body of literature examining neurocognitive and academic benefits conferred to children following exposure to formal schooling.

Children transition from simple associations to explicitly reasoned social learning strategies between age four and eight.

To differentiate the use of simple associations from use of explicitly reasoned selective social learning, we can look for age-related changes in children's behaviour that might signify a switch from one social learning strategy to the other. We presented 4- to 8-year-old children visiting a zoo in Scotland (N = 109) with a task in which the perceptual access of two informants was determined by the differing opacity of two screens of similar visual appearance during a hiding event. Initially success could be achieved by forming an association or inferring a rule based on salient visual (but causally irrelevant) cues. However, following a switch in the scenario, success required explicit reasoning about informants' potential to provide valuable information based on their perceptual access. Following the switch, older children were more likely to select a knowledgeable informant. This suggests that some younger children who succeeded in the pre-switch trials had inferred rules or formed associations based on superficial, yet salient, visual cues, whereas older children made the link between perceptual access and the potential to inform. This late development and apparent cognitive challenge are consistent with proposals that such capacities are linked to the distinctiveness of human cumulative culture.

Disentangling age and schooling effects on inhibitory control development: An fNIRS investigation.

Children show marked improvements in executive functioning (EF) between 4 and 7 years of age. In many societies, this time period coincides with the start of formal school education, in which children are required to follow rules in a structured environment, drawing heavily on EF processes such as inhibitory control. This study aimed to investigate the longitudinal development of two aspects of inhibitory control, namely response inhibition and response monitoring and their neural correlates. Specifically, we examined how their longitudinal development may differ by schooling experience, and their potential significance in predicting academic outcomes. Longitudinal data were collected in two groups of children at their homes. At T1, all children were roughly 4.5 years of age and neither group had attended formal schooling. One year later at T2, one group (P1, n = 40) had completed one full year of schooling while the other group (KG, n = 40) had stayed in kindergarten. Behavioural and brain activation data (measured with functional near-infrared spectroscopy, fNIRS) in response to a Go/No-Go task and measures of academic achievement were collected. We found that P1 children, compared to KG children, showed a greater change over time in activation related to response monitoring in the bilateral frontal cortex. The change in left frontal activation difference showed a small positive association with math performance. Overall, the school environment is important in shaping the development of the brain functions underlying the monitoring of one own's performance.

Taking account of others' goals in social information use: Developmental changes in 3- to 7-year-old children.

The ability to take mental states such as goals into account when interpreting others' behavior has been proposed to be what sets human use of social information apart from that of other animals. If so, children's social information use would be expected to change as their understanding of others' mental states develops. We explored age-related changes in 3- to 7-year-old children's ability to strategically use social information by taking into account another's goal when it was, or was not, aligned with their own. Children observed as a puppet demonstrator selected a capsule, peeked inside, and chose to accept or reject it, following which children made their own selection. Children were able to account for others' conflicting motivations from around 4 years of age and reliably inferred the outcome of others' behavior from 6 years. However, using social information based on such inferences appeared to be challenging regardless of whether the demonstrator's goal was, or was not. aligned to that of the participant. We found that social information use improved with age; however, this improvement was restricted to cases in which the appropriate response was to avoid copying the demonstrator's selection. In contrast to previous research, appropriate copying responses remained at chance. Possible explanations for this unexpected pattern of results are discussed. The cognitive challenge associated with the ability to account for others' goals could offer humans a significant advantage over that of other animals in their ability to use social information.

Development of strategic social information seeking: Implications for cumulative culture.

Human learners are rarely the passive recipients of valuable social information. Rather, learners usually have to actively seek out information from a variety of potential others to determine who is in a position to provide useful information. Yet, the majority of developmental social learning paradigms do not address participants' ability to seek out information for themselves. To investigate age-related changes in children's ability to seek out appropriate social information, 3- to 8-year-olds (N = 218) were presented with a task requiring them to identify which of four possible demonstrators could provide critical information for unlocking a box. Appropriate information seeking improved significantly with age. The particularly high performance of 7- and 8-year-olds was consistent with the expectation that older children's increased metacognitive understanding would allow them to identify appropriate information sources. Appropriate social information seeking may have been overlooked as a significant cognitive challenge involved in fully benefiting from others' knowledge, potentially influencing understanding of the phylogenetic distribution of cumulative culture.

Home assessment of visual working memory in pre-schoolers reveals associations between behaviour, brain activation and parent reports of life stress.

Visual working memory (VWM) is reliably predictive of fluid intelligence and academic achievements. The objective of the current study was to investigate individual differences in pre-schoolers' VWM processing by examining the association between behaviour, brain function and parent-reported measures related to the child's environment. We used a portable functional near-infrared spectroscopy system to record from the frontal and parietal cortices of 4.5-year-old children (N = 74) as they completed a colour change-detection VWM task in their homes. Parents were asked to fill in questionnaires on temperament, academic aspirations, home environment and life stress. Children were median-split into a low-performing (LP) and a high-performing (HP) group based on the number of items they could successfully remember during the task. LPs increasingly activated channels in the left frontal and bilateral parietal cortices with increasing load, whereas HPs showed no difference in activation. Our findings suggest that LPs recruited more neural resources than HPs when their VWM capacity was challenged. We employed mediation analyses to examine the association between the difference in activation between the highest and lowest loads and variables from the questionnaires. The difference in activation between loads in the left parietal cortex partially mediated the association between parent-reported stressful life events and VWM performance. Critically, our findings show that the association between VWM capacity, left parietal activation and indicators of life stress is important to understand the nature of individual differences in VWM in pre-school children.

Cognitive prerequisites for cumulative culture are context-dependent: Children's potential for ratcheting depends on cue longevity.

Human cumulative culture has been suggested to depend on human-unique cognitive mechanisms, explaining its apparent absence in other species. We show that the potential for exhibiting cumulative culture depends on the cognitive abilities of the agents and the demands associated with using information generated by others' activity. 154 children aged 3-6 years played a searching game ("Find the Treasure"), taking their turn after a puppet demonstrator. The puppet's attempt revealed information about the contents of the locations searched, which could be exploited to target rewarded locations, and avoid unrewarded ones. Two conditions were presented, intended to capture realistic variation in the transience of the cues generated by another individual's activity. In one condition, the puppet's demonstration provided transient information - boxes were opened, seen to be rewarded or not, and then closed. In the other condition the puppet's chosen boxes remained partially open, providing an enduring visible cue as to whether that location was rewarded. Children undertook three trials of varying demonstration success, and we used patterns of performance to infer the potential for improvement over multiple generations of transmission. In the Enduring Cues condition, children's performance demonstrated the potential for cumulative culture. In contrast, in the Transient Information condition, only older children showed improved performances following higher success demonstrations and overall performance was not compatible with the possibility of improvements over generations of social transmission. We conclude that under certain conditions cumulative culture could occur in many species, but in a broader range of contexts in humans.

Extended difficulties with counterfactuals persist in reasoning with false beliefs: Evidence for teleology-in-perspective.

Increasing evidence suggests that counterfactual reasoning is involved in false belief reasoning. Because existing work is correlational, we developed a manipulation that revealed a signature of counterfactual reasoning in participants' answers to false belief questions. In two experiments, we tested 3- to 14-year-olds and found high positive correlations (r = .56 and r = .73) between counterfactual and false belief questions. Children were very likely to respond to both questions with the same answer, also committing the same type of error. We discuss different theories and their ability to account for each aspect of our findings and conclude that reasoning about others' beliefs and actions requires similar cognitive processes as using counterfactual suppositions. Our findings question the explanatory power of the traditional frameworks, theory theory and simulation theory, in favor of views that explicitly provide for a relationship between false belief reasoning and counterfactual reasoning.

Children struggle beyond preschool-age in a continuous version of the ambiguous figures task.

Children until the age of five are only able to reverse an ambiguous figure when they are informed about the second interpretation. In two experiments, we examined whether children's difficulties would extend to a continuous version of the ambiguous figures task. Children (Experiment 1: 66 3- to 5-year olds; Experiment 2: 54 4- to 9-year olds) and adult controls saw line drawings of animals gradually morph-through well-known ambiguous figures-into other animals. Results show a relatively late developing ability to recognize the target animal, with difficulties extending beyond preschool-age. This delay can neither be explained with improvements in theory of mind, inhibitory control, nor individual differences in eye movements. Even the best achieving children only started to approach adult level performance at the age of 9, suggesting a fundamentally different processing style in children and adults.

The role of context in "over-imitation": Evidence of movement-based goal inference in young children.

Children, as well as adults, often imitate causally unnecessary actions. Three experiments investigated whether such "over-imitation" occurs because these actions are interpreted as performed for the movement's sake (i.e., having a "movement-based" goal). Experiment 1 (N = 30, 2-5-year-olds) replicated previous findings; children imitated actions with no goal more precisely than actions with external goals. Experiment 2 (N = 58, 2-5-year-olds) confirmed that the difference between these conditions was not due to the absence/presence of external goals but rather was also found when actions brought about external goals in a clearly inefficient way. Experiment 3 (N = 36, 3-5-year-olds) controlled for the possibility that imitation fidelity was affected by the number of actions and objects present during the demonstration and confirmed that identical actions were imitated more precisely when they appeared to be more inefficient toward an external goal. Our findings suggest that movement-based goal inference encourages over-imitation.

Are counterfactuals in and about time?

We discuss whether the two systems approach can advance understanding of children's developing counterfactual thinking. We argue that types of counterfactual thinking that are acquired early in development could be handled by the temporal updating system, whereas those that emerge in middle childhood require thinking about specific events in time.

Belief and Counterfactuality: A Teleological Theory of Belief Attribution.

The development and relation of counterfactual reasoning and false belief understanding were examined in 3- to 7-year-old children (N = 75) and adult controls (N = 14). The key question was whether false belief understanding engages counterfactual reasoning to infer what somebody else falsely believes. Findings revealed a strong correlation between false belief and counterfactual questions even in conditions in which children could commit errors other than the reality bias (r p  = .51). The data suggest that mastery of belief attribution and counterfactual reasoning is not limited to one point in development but rather develops over a longer period. Moreover, the rare occurrence of reality errors calls into question whether young children's errors in the classic false belief task are indeed the result of a failure to inhibit what they know to be actually the case. The data speak in favor of a teleological theory of belief attribution and challenges established theories of belief attribution.

Helping as an early indicator of a theory of mind: Mentalism or Teleology?

This article challenges the claim that young children's helping responses in Buttelmann, Carpenter, and Tomasello's (2009) task are based on ascribing a false belief to a mistaken agent. In our first Study 18- to 32-month old children (N = 28) were more likely to help find a toy in the false belief than in the true belief condition. In Study 2, with 54 children of the same age, we assessed the authors' mentalist interpretation of this result against an alternative teleological interpretation that does not make the assumption of belief ascription. The data speak in favor of our alternative. Children's social competency is based more on inferences about what is likely to happen in a particular situation and on objective reasons for action than on inferences about agents' mental states. We also discuss the need for testing serious alternative interpretations of claims about early belief understanding.

Counterfactual Reasoning: Sharpening Conceptual Distinctions in Developmental Studies.

Counterfactual reasoning (CFR)-mentally representing what the world would be like now if things had been different in the past-is an important aspect of human cognition and the focus of research in areas such as philosophy, social psychology, and clinical psychology. More recently, it has also gained broad interest in cognitive developmental psychology, mainly focusing on the question of how this kind of reasoning can be characterized. Studies have been inconsistent in identifying when children can use CFR. In this article, we present theoretical positions that may account for this inconsistency and evaluate them in the light of research on counterfactual emotions.

Basic Conditional Reasoning: How Children Mimic Counterfactual Reasoning.

Children approach counterfactual questions about stories with a reasoning strategy that falls short of adults' Counterfactual Reasoning (CFR). It was dubbed "Basic Conditional Reasoning" (BCR) in Rafetseder et al. (Child Dev 81(1):376-389, 2010). In this paper we provide a characterisation of the differences between BCR and CFR using a distinction between permanent and nonpermanent features of stories and Lewis/Stalnaker counterfactual logic. The critical difference pertains to how consistency between a story and a conditional antecedent incompatible with a nonpermanent feature of the story is achieved. Basic conditional reasoners simply drop all nonpermanent features of the story. Counterfactual reasoners preserve as much of the story as possible while accommodating the antecedent.

Counterfactual reasoning: from childhood to adulthood.

The objective of this study was to describe the developmental progression of counterfactual reasoning from childhood to adulthood. In contrast to the traditional view, it was recently reported by Rafetseder and colleagues that even a majority of 6-year-old children do not engage in counterfactual reasoning when asked counterfactual questions (Child Development, 2010, Vol. 81, pp. 376-389). By continuing to use the same method, the main result of the current Study 1 was that performance of the 9- to 11-year-olds was comparable to that of the 6-year-olds, whereas the 12- to 14-year-olds approximated adult performance. Study 2, using an intuitively simpler task based on Harris and colleagues (Cognition, 1996, Vol. 61, pp. 233-259), resulted in a similar conclusion, specifically that the ability to apply counterfactual reasoning is not fully developed in all children before 12 years of age. We conclude that children who failed our tasks seem to lack an understanding of what needs to be changed (events that are causally dependent on the counterfactual assumption) and what needs to be left unchanged and so needs to be kept as it actually happened. Alternative explanations, particularly executive functioning, are discussed in detail.

When the alternative would have been better: counterfactual reasoning and the emergence of regret.

Counterfactual reasoning about how events could have turned out better is associated with the feeling of regret. However, developmental studies show a discrepancy between the onset of counterfactual reasoning (at 3 years) and the feeling of regret (at 6 years). In four experiments we explored possible reasons. Experiment 1 (3- to 6-year-old children) and Experiment 2 (adult control) show that even when regret is assessed more directly than in previous studies (e.g., Amsel & Smalley, 2000) only adults but not children regret their decision. Experiment 3 (3- to 14-year-old children) suggests that double-questioning--asking children how happy they are with what they got before and after they had seen what they could have got--creates false positive indications of regret in the youngest children and that--when controlling for false positives--regret is not evident before 9 years. However, children before this age make a difference between attractive (three candies) and less attractive (one candy) items (Experiment 4; 6- to 8-year-old children). Taken together, this suggests that before 9 years of age children base their judgements solely on what they got without taking into account what they could have got.

Counterfactual reasoning: developing a sense of "nearest possible world".

This study investigated at what point in development 3- to 6-year-old children begin to demonstrate counterfactual reasoning by controlling for fortuitously correct answers that result from basic conditional reasoning. Basic conditional reasoning occurs when one applies typical regularities (such as "If 'whenever' it doesn't rain the street is dry") to counterfactual questions (such as "If it had not rained, would the street be wet or dry?") without regard to actual events (e.g., if street cleaners had just been washing the street). In counterfactual reasoning, however, the conditional reasoning must be constrained by actual events (according to the "nearest possible world"). In situations when counterfactual reasoning and basic conditional reasoning would yield the same answers, even the youngest children gave mostly correct answers. However, tasks in which the 2 reasoning strategies resulted in different answers proved unusually difficult even for the older children.

Is reasoning from counterfactual antecedents evidence for counterfactual reasoning?

In most developmental studies the only error children could make on counterfactual tasks was to answer with the current state of affairs. It was concluded that children who did not show this error are able to reason counterfactually. However, children might have avoided this error by using basic conditional reasoning (Rafetseder, Cristi-Vargas, & Perner, 2010). Basic conditional reasoning takes an antecedent, which like in counterfactual reasoning can be counter to fact, and combines it with a conditional (or set of conditionals reflecting knowledge of how the world works) to draw a likely conclusion. A critical feature of counterfactual reasoning then is that these additional assumptions be modelled after the actual events to which the counterfactual is taken to be counterfactual. In contrast in basic conditional reasoning one enriches the given antecedent with any plausible assumptions. In our tasks basic conditional reasoning leads to different answers than counterfactual reasoning. For instance, a doctor, sitting in the park with the intention to read a paper, is called to an emergency at the swimming pool. The question, "if there had been no emergency, where would the doctor be?" should counterfactually be answered "in the park". But ignoring the doctor's intentions and just reasoning on plausible grounds one might answer: "in the hospital". Only by 6 years, did children give mostly correct answers.