Number sense at 12 months predicts 4-year-olds' maths skills.

Preverbal infants spontaneously represent the number of objects in collections. Is this 'sense of number' (also referred to as Approximate Number System, ANS) part of the cognitive foundations of mathematical skills? Multiple studies reported a correlation between the ANS and mathematical achievement in children. However, some have suggested that such correlation might be mediated by general-purpose inhibitory skills. We addressed the question using a longitudinal approach: we tested the ANS of 60 12 months old infants and, when they were 4 years old (final N = 40), their symbolic math achievement as well as general intelligence and inhibitory skills. Results showed that the ANS at 12 months is a specific predictor of later maths skills independent from general intelligence or inhibitory skills. The correlation between ANS and maths persists when both abilities are measured at four years. These results confirm that the ANS has an early, specific and longstanding relation with mathematical abilities in childhood. RESEARCH HIGHLIGHTS: In the literature there is a lively debate about the correlation between the ANS and maths skills. We longitudinally tested a sample of 60 preverbal infants at 12 months and rested them at 4 years (final sample of 40 infants). The ANS tested at 12 months predicted later symbolic mathematical skills at 4 years, even when controlling for inhibition, general intelligence and perceptual skills. The ANS tested at 4 years remained linked with symbolic maths skills, confirming this early and longstanding relation in childhood.

Preverbal infants' reactions to third-party punishments and rewards delivered toward fair and unfair agents.

Rewarding individuals who distribute resources fairly and punishing those who distribute resources unfairly may be very important actions for fostering cooperation. This study investigated whether 9-month-olds have some expectations concerning punishments and rewards that follow distributive actions. Infants were shown simple animations and were tested using the violation-of-expectation paradigm. In Experiment 1, we found that infants looked longer when they saw a bystander delivering a corporal punishment to a 'fair distributor,' who distributed some windfall resources equally to the possible recipients, rather than to an 'unfair distributor,' who distributed the resources unequally. This pattern of looking times was reversed when, in Experiment 2, punishments were replaced with rewards. These findings suggest an early emergence of expectations about punishing and rewarding actions in third-party contexts, and they help to evaluate competing claims about the origins of a sense of fairness.

Infants' intention-based evaluations of distributive actions.

Recent research revealed that infants attend to agents' intentions when they evaluate helping actions. The current study investigated whether infants also consider agents' intentions when they evaluate distributive actions. In Experiment 1, 9-month-old infants were first shown two failed attempts to perform a distribution. In the "failed equal distribution," the distributor first tried to reach one of the recipients to deliver an apple, failed, and then attempted to reach the other possible recipient to deliver a different apple and also failed. In the "failed unequal distribution," a different distributor always tried unsuccessfully to reach the same beneficiary. Then, in the test phase, infants were presented with the two distributors side by side, and infants' spontaneous preferential looking and reaching actions were recorded. We found a reliable preference for the equal distributor in both the visual and manual responses. Experiments 2 and 3 helped to rule out alternative explanations based on perceptual cues and affiliative biases. Overall, these findings suggest that infants' ability to evaluate distributive actions relies not only on the outcomes but also on the distributors' intentions.

Infants' preferences for approachers over repulsers shift between 4 and 8 months of age.

Despite its adaptive value for social life, the emergence and the development of the ability to detect agents that cause aversive interactions and distinguish them from potentially affiliative agents (approachers) has not been investigated. We presented infants with a simple interaction involving two agents: one of them (the "repulser") moved toward and pushed the other (the "approacher") which reacted by simply moving toward the repulser without contacting it. We found that 8-month-olds (N = 28) looked longer at the approacher than at the repulser (Experiment 1), whereas 4-month-olds (N = 30) exhibited no preference (Experiment 2). To control for low-level cues (such as the preference for the agent that moved after the contact), two new groups of 4- and 8-month-old infants were presented with a series of interactions in which the agents inverted their social roles. Older infants (N = 30) manifested no preference for either agent (Experiment 3), while younger infants (N = 30) looked longer at the first agent to move (Experiment 4). Our results indicated that 8-month-olds' preferences for the approacher over the repulser depended on social information and were finely tuned to agents that display prosocial rather than antisocial behavior. We discuss these findings in light of the development and adaptive value of the ability to negatively evaluate repulsers, to avoid choosing them as partners.

Infants distinguish between leaders and bullies.

We examined whether 21-month-old infants could distinguish between two broad types of social power: respect-based power exerted by a leader (who might be an authority figure with legitimate power, a prestigious individual with merited power, or some combination thereof) and fear-based power exerted by a bully. Infants first saw three protagonists interact with a character who was either a leader (leader condition) or a bully (bully condition). Next, the character gave an order to the protagonists, who initially obeyed; the character then left the scene, and the protagonists either continued to obey (obey event) or no longer did so (disobey event). Infants in the leader condition looked significantly longer at the disobey than at the obey event, suggesting that they expected the protagonists to continue to obey the leader in her absence. In contrast, infants in the bully condition looked equally at the two events, suggesting that they viewed both outcomes as plausible: The protagonists might continue to obey the absent bully to prevent further harm, or they might disobey her because her power over them weakened in her absence. Additional results supported these interpretations: Infants expected obedience when the bully remained in the scene and could harm the protagonists if defied, but they expected disobedience when the order was given by a character with little or no power over the protagonists. Together, these results indicate that by 21 months of age, infants already hold different expectations for subordinates' responses to individuals with respect-based as opposed to fear-based power.

Toddlers' expectations of third-party punishments and rewards following an act of aggression.

Rewarding someone who defends the victim of an unjust aggression and punishing someone who chose not to defend her may be very important acts of reciprocation in social life. This study investigates whether 21-month-olds have some expectations concerning such punishing and rewarding actions. Infants were shown simple puppet shows and were tested using the violation-of-expectation paradigm. In Experiment 1, we found that infants looked longer when they saw a bystander puppet punishing the puppet who defended the victim rather than the puppet who did not defend her. This pattern of looking times was reversed when the punishing action was replaced with a rewarding action (Experiment 2). These findings reveal early-emerging expectations about punitive and reward motivations in third-party contexts, and provide some support for theoretical claims about the hardwiring of the human mind for cooperation and prosociality.

Scalar and ad-hoc pragmatic inferences in children: guess which one is easier.

Several studies investigated preschoolers' ability to compute scalar and ad-hoc implicatures, but only one compared children's performance with both kinds of implicature with the same task, a picture selection task. In Experiment 1 (N = 58, age: 4;2-6;0), we first show that the truth value judgment task, traditionally employed to investigate children's pragmatic ability, prompts a rate of pragmatic responses comparable to the picture selection task. In Experiment 2 (N = 141, age: 3;8-9;2) we used the picture selection task to compare scalar and ad-hoc implicatures and linked the ability to derive these implicatures to some cognitive and linguistic measures. We found that four- and five-year-olds children performed better on ad-hoc than on scalar implicatures. Furthermore, we found that morphosyntactic competence was associated with success in both kinds of implicatures, while performance on mental state reasoning was positively associated with success on scalar but not ad-hoc implicatures.

First steps toward an understanding of procedural fairness.

In four experiments, we tested whether 20-month-old infants are sensitive to violations of procedural impartiality. Participants were shown videos in which help was provided in two different ways. A main character provided help to two other agents either impartially, by helping them at the same time, or in a biased way, by helping one agent almost immediately while the other after a longer delay. Infants looked reliably longer at the biased than at the unbiased help scenarios despite the fact that in both scenarios help was provided to each beneficiary. This suggests that human infants can attend to departures from impartiality and, in their second year, they already show an initial understanding of procedural fairness.

On the domain specificity of the mechanisms underpinning spontaneous anticipatory looks in false-belief tasks.

Many studies proposed that infants' and adults' looking behavior suggest a spontaneous and implicit ability to reason about others' beliefs. It has been argued, however, that these successes are false positives due to domain-general processes, such as retroactive interference. In this study, we investigated the domain specificity of mechanisms underpinning participants' looking behavior by manipulating the dynamic cues in the event stimuli. Infants aged 15 and 20 months and adults saw animation events in which either a self-moving triangle, or a hand holding an identical inert triangle, chased an animated disk. Most 20-month-olds and adults showed belief congruent anticipatory looks in the agent-triangle condition, whereas they showed no bias in the inert triangle control condition. These results are not consistent with submentalizing accounts based on domain-general low-level processes and provide further support for domain-specific explanations positing an early-emerging mentalistic reasoning.

Conceptual continuity in the development of intent-based moral judgment.

When asked to say whether an agent is morally good or bad, younger preschoolers tend to rely more on the outcomes of agents' actions than on agents' intentions, whereas older children show the opposite bias. Children aged 3 to 5 years were examined with a novel task that facilitated the selection and expression of response by means of response generation training. In two experiments, we found that 3-year-olds succeeded in generating intent-based judgments when the task was simplified, whereas older preschoolers succeeded also without the help of response generation training. Results are inconsistent with views positing a conceptual change occurring in the moral domain at about 4 years of age and provide support for alternative accounts positing conceptual continuity.

Infants' use of motion cues in object individuation processes.

We investigated 10-month-old infants' and adults' numerical expectations in scenarios where information on self-motion and static object features may give rise to numerically incongruent representations. A red circle or a blue box with yellow stripes appeared on the left side of a screen, moved autonomously sideways and then moved back behind the screen. Next, on the opposite side, an identical object was first brought in view by a hand and then pushed back behind the screen (Experiments 1 and 2). The screen was finally removed, revealing either one or two objects. Infants looked longer at one-object test events, suggesting that they expected to find two objects. Adults were also shown these animations and were asked for their numerical expectations. Contrary to infants, they expected one single object (Experiment 3). Whereas preverbal infants' numerical expectations appeared to be dominated by information on object autonomous and induced motion, adults' expectations were mainly guided by information about object shape, size, and color. These findings were discussed in relation to current models on the development of object individuation processes.

Lexical stress contrastivity in Italian children with autism spectrum disorders: an exploratory acoustic study.

We investigated production of lexical stress in children with and without autism spectrum disorders (ASD), all monolingual Italian speakers. The mean age of the 16 autistic children was 5.73 years and the mean age of the 16 typically developing children was 4.65 years. Picture-naming targets were five trisyllabic words that began with a weak-strong pattern of lexical stress across the initial two syllables (WS: matita) and five trisyllabic words beginning with a strong-weak pattern (SW: gomito). Acoustic measures of the duration, fundamental frequency, and intensity of the first two vowels for correct word productions were used to calculate a normalised Pairwise Variability Index (PVI) for WS and SW words. Results of acoustic analyses indicated no statistically significant group differences in PVIs. Results should be interpreted in line with the exploratory nature of this study. We hope this study will encourage additional cross-linguistic studies of prosody in children's speech production.

Many moral buttons or just one? Evidence from emotional facial expressions.

We investigated whether moral violations involving harm selectively elicit anger, whereas purity violations selectively elicit disgust, as predicted by the Moral Foundations Theory (MFT). We analysed participants' spontaneous facial expressions as they listened to scenarios depicting moral violations of harm and purity. As predicted by MFT, anger reactions were elicited more frequently by harmful than by impure actions. However, violations of purity elicited more smiling reactions and expressions of anger than of disgust. This effect was found both in a classic set of scenarios and in a new set in which the different kinds of violations were matched on weirdness. Overall, these findings are at odds with predictions derived from MFT and provide support for "monist" accounts that posit harm at the basis of all moral violations. However, we found that smiles were differentially linked to purity violations, which leaves open the possibility of distinct moral modules.

Toddlers map the word 'good' to helping agents, but not to fair distributors.

Infants begin to understand some of the meanings of the adjective good at around thirteen months, but it is not clear when they start to map it to concepts in the moral domain. We investigated infants' and toddlers' knowledge of good in the domains of help and fairness. Participants at 20 and 30 months were shown computer animations involving helpful and hindering agents, or agents who performed fair or unfair distributions, and were asked to "pick the good one". Toddlers at 30 months took good as referring to helping, but not to the fair agents. However, when asked "to pick one", they choose the fair distributor. These findings suggest that by 30 months toddlers have started to map good to some socio-moral features, such as a helping disposition, but not to fairness in distributive actions.

The violation-of-expectation paradigm: A conceptual overview.

For over 35 years, the violation-of-expectation paradigm has been used to study the development of expectations in the first 3 years of life. A wide range of expectations has been examined, including physical, psychological, sociomoral, biological, numerical, statistical, probabilistic, and linguistic expectations. Surprisingly, despite the paradigm's widespread use and the many seminal findings it has contributed to psychological science, so far no one has tried to provide a detailed and in-depth conceptual overview of the paradigm. Here, we attempted to do just that. We first focus on the rationale of the paradigm and discuss how it has evolved over time. We then show how improved descriptions of infants' looking behavior, together with the addition of a rich panoply of brain and behavioral measures, have helped deepen our understanding of infants' responses to violations. Next, we review the paradigm's strengths and limitations. Finally, we end with a discussion of challenges that have been leveled against the paradigm over the years. Through it all, our goal was twofold. First, we sought to provide psychologists and other scientists interested in the paradigm with an informed and constructive analysis of its theoretical origins and development. Second, we wanted to take stock of what the paradigm has revealed to date about how infants reason about events, and about how surprise at unexpected events, in or out of the laboratory, can lead to learning, by prompting infants to revise their working model of the world. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

False belief understanding in deaf children: what are the difficulties?

Children with cochlear implants (CIs) demonstrate proficiency in verbal-story elicited-response (VS-ER) false-belief tasks, such as the Sally & Ann task, at a similar age as typically developing hearing children. However, they face challenges in non-verbal spontaneous-response (NV-SR) false-belief tasks, measured via looking times, which hearing infants typically pass by around 2 years of age, or earlier. The purpose of the present study was to examine whether these difficulties remain in a non-verbal-story elicited-response (NVS-ER) false-belief task, in which children are offered the opportunity to provide an elicited response to a non-verbal-story task. A total of thirty 4- to 8-year-old children with CI-s and hearing children completed three different kinds of false-belief tasks. The results showed that children with CI-s performed above chance level on the verbal task (i.e., VS-ER task), but not on the two non-verbal tasks, (i.e., NVS-ER and NV-SR tasks). The control group of typically developing hearing children performed above chance on all three kinds of tasks (one-tailed significance level). Our findings highlight the importance of external narrative support for children with CIs in tasks that involve mental perspective-taking, and specifically predicting actions based on false beliefs.

Intention-based evaluations of distributive actions by 4-month-olds.

Four-month-olds' ability to consider the intentions of agents performing distributive actions was investigated in four experiments, using the Violation of Expectation paradigm (VoE) (Experiments 1-3) and the Preferential Looking paradigm (Experiment 4). In Experiment 1, infants were presented with two events showing two types of failed attempts to perform a distribution. In an attempt to distribute fairly, the distributor first tried to reach one of the recipients to deliver an apple, he failed, and then attempted to reach the other recipient to deliver a second apple and also failed. In an attempt to distribute unfairly, a different distributor tried unsuccessfully to bring resources always to the same recipient. Infants looked reliably longer at failed fair distribution events, suggesting that they did not just react to the actions outcomes and they attended to agents' intentions. Experiments 2 and 3 assessed alternative explanations based on perceptual factors or affiliative behaviors. In Experiment 4, during the test trials, infants were shown both distributors simultaneously and they preferred to look at the fair rather than at the unfair distributor. Overall, these findings reveal an early ability to take into account distributors' intentions and a preference for watching agents that tried to distribute resources fairly.

Age-Related Differences in Moral Judgment: The Role of Probability Judgments.

Research suggests that moral evaluations change during adulthood. Older adults (75+) tend to judge accidentally harmful acts more severely than younger adults do, and this age-related difference is in part due to the greater negligence older adults attribute to the accidental harmdoers. Across two studies (N = 254), we find support for this claim and report the novel discovery that older adults' increased attribution of negligence, in turn, is associated with a higher perceived likelihood that the accident would occur. We propose that, because older adults perceive accidents as more likely than younger adults do, they condemn the agents and their actions more and even infer that the agents' omission to exercise due care is intentional. These findings refine our understanding of the cognitive processes underpinning moral judgment in older adulthood and highlight the role of subjective probability judgments in negligence attribution.

Belief attribution in deaf and hearing infants.

Based on anticipatory looking and reactions to violations of expected events, infants have been credited with 'theory of mind' (ToM) knowledge that a person's search behaviour for an object will be guided by true or false beliefs about the object's location. However, little is known about the preconditions for looking patterns consistent with belief attribution in infants. In this study, we compared the performance of 17- to 26-month-olds on anticipatory looking in ToM tasks. The infants were either hearing or were deaf from hearing families and thus delayed in communicative experience gained from access to language and conversational input. Hearing infants significantly outperformed their deaf counterparts in anticipating the search actions of a cartoon character that held a false belief about a target-object location. By contrast, the performance of the two groups in a true belief condition did not differ significantly. These findings suggest for the first time that access to language and conversational input contributes to early ToM reasoning.

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.