Infants are sensitive to the social signaling value of shared inefficient behaviors.

Actions that are blatantly inefficient to achieve non-social goals are often used to convey information about agents' social affiliation, as in the case of rituals. We argue that when reproduced, actions that are individually inefficient acquire a social signaling value owing to the mechanisms that support humans' intuitive analysis of actions. We tested our hypothesis on 15-month-old infants who were familiarized with an agent that reproduced or merely observed the actions of efficient and inefficient individuals.

Expectations of Processing Ease, Informativeness, and Accuracy Guide Toddlers' Processing of Novel Communicative Cues.

Discovering the meaning of novel communicative cues is challenging and amounts to navigating an unbounded hypothesis space. Several theories posit that this problem can be simplified by relying on positive expectations about the cognitive utility of communicated information. These theories imply that learners should assume that novel communicative cues tend to have low processing costs and high cognitive benefits.

Infants' representation of asymmetric social influence.

In social groups, some individuals have more influence than others, for example, because they are learned from or because they coordinate collective actions. Identifying these influential individuals is crucial to learn about one's social environment. Here, we tested whether infants represent asymmetric social influence among individuals from observing the imitation of movements in the absence of any observable coercion or order.

Infants expect agents to minimize the collective cost of collaborative actions.

This paper argues that human infants address the challenges of optimizing, recognizing, and interpreting collaborative behaviors by assessing their collective efficiency. This hypothesis was tested by using a looking-time study. Fourteen-month-olds (N = 32) were familiarized with agents performing a collaborative action in computer animations.

Are monkeys sensitive to informativeness: An experimental study with baboons (Papio papio).

Informativeness (defined as reduction of uncertainty) is central in human communication. In the present study, we investigate baboons' sensitivity to informativeness by manipulating the informativity of a cue relative to a response display and by allowing participants to anticipate their answers or to wait for a revealed answer (with variable delays). Our hypotheses were that anticipations would increase with informativity, while response times to revealed trials would decrease with informativity.

Knowledge in Sight: Toddlers Plan Efficient Epistemic Actions by Anticipating Learning Gains.

Anticipating the learning consequences of actions is crucial to plan efficient information seeking. Such a capacity is needed for learners to determine which actions are most likely to result in learning. Here, we tested the early ontogeny of the human capacity to anticipate the amount of learning gained from seeing.

The origins of trust: Humans' reliance on communicative cues supersedes firsthand experience during the second year of life.

How do people learn about things that they have never perceived or inferred-like molecules, miracles or Marie-Antoinette? For many thinkers, trust is the answer. Humans rely on communicated information, sometimes even when it contradicts blatantly their firsthand experience. We investigate the early ontogeny of this trust using a non-verbal search paradigm in four main studies and three supplementary studies (N = 208).

How do we interpret questions? Simplified representations of knowledge guide humans' interpretation of information requests.

This paper investigates the cognitive mechanisms supporting humans' interpretation of requests for information. Learners can only search for a piece of information if they know that they are ignorant about it. Thus, in principle, the interpretation of requests for information could be guided by representations of Socratic ignorance (tracking what people know that they do not know).

The effect of disagreement on children's source memory performance.

Source representations play a role both in the formation of individual beliefs as well as in the social transmission of such beliefs. Both of these functions suggest that source information should be particularly useful in the context of interpersonal disagreement. Three experiments with an identical design (one original study and two replications) with 3- to 4-year-old-children (N = 100) assessed whether children's source memory performance would improve in the face of disagreement and whether such an effect interacts with different types of sources (first- vs.

The pragmatic role of trust in young children's interpretation of unfamiliar signals.

What role does children's trust in communication play in their acquisition of new meanings? To answer, we report two experimental studies (N = 81) testing how three- to four-year-olds interpret the meaning of a novel communicative device when it is used by a malevolent and potentially deceptive informant. Children participated in a hiding game in which they had to find a reward hidden in one of two boxes. In the initial phase of the experiments, a malevolent informant always indicated the location of the empty box using a novel communicative device, either a marker (Study 1), or an arrow (Study 2).

Nonverbal rhetoric: 2- to 4-year-old children select relevant evidence when trying to influence others.

This article investigates the early emergence of reason-giving. Toddlers are sensitive to disagreements, and they can track several kinds of informational access, such as visual perception. We investigated whether young children use these skills (a) when assessing whether providing reasons is needed and (b) when selecting appropriate behaviors to support their claims.

Infants discriminate the source of social touch at stroking speeds eliciting maximal firing rates in CT-fibers.

The evaluation of interpersonal touch is heavily influenced by its source. For example, a gentle stroke from a loved one is generally more pleasant than the same tactile stimulation from a complete stranger. Our study tested the early ontogenetic roots of humans' sensitivity to the source of interpersonal touch.

Optimistic expectations about communication explain children's difficulties in hiding, lying, and mistrusting liars.

We suggest that preschoolers' frequent obliviousness to the risks and opportunities of deception comes from a trusting stance supporting verbal communication. Three studies (N = 125) confirm this hypothesis. Three-year-olds can hide information from others (Study 1) and they can lie (Study 2) in simple settings.

Statistical treatment of looking-time data.

Looking times (LTs) are frequently measured in empirical research on infant cognition. We analyzed the statistical distribution of LTs across participants to develop recommendations for their treatment in infancy research. Our analyses focused on a common within-subject experimental design, in which longer looking to novel or unexpected stimuli is predicted.

Probing the Strength of Infants' Preference for Helpers over Hinderers: Two Replication Attempts of Hamlin and Wynn (2011).

Several studies indicate that infants prefer individuals who act prosocially over those who act antisocially toward unrelated third parties. In the present study, we focused on a paradigm published by Kiley Hamlin and Karen Wynn in 2011. In this study, infants were habituated to a live puppet show in which a protagonist tried to open a box to retrieve a toy placed inside.

Epistemology for Beginners: Two- to Five-Year-Old Children's Representation of Falsity.

This paper investigates the ontogeny of human's naive concept of truth. Surprisingly, children find it hard to treat assertions as false before their fifth birthday. Yet, we show in six studies (N = 140) that human's concept of falsity develops early.

Human infants' learning of social structures: the case of dominance hierarchy.

We tested 15-month-olds' capacity to represent social-dominance hierarchies with more than two agents. Our results showed that infants found it harder to memorize dominance relations that were presented in an order that hindered the incremental formation of a single structure (Study 1). These results suggest that infants attempt to build structures incrementally, relation by relation, thereby simplifying the complex problem of recognizing a social structure.

Representation of stable social dominance relations by human infants.

What are the origins of humans' capacity to represent social relations? We approached this question by studying human infants' understanding of social dominance as a stable relation. We presented infants with interactions between animated agents in conflict situations. Studies 1 and 2 targeted expectations of stability of social dominance.

Preschoolers are able to take merit into account when distributing goods.

Classic studies in developmental psychology demonstrate a relatively late development of equity, with children as old as 6 or even 8-10 years failing to follow the logic of merit--that is, giving more to those who contributed more. Following Piaget (1932), these studies have been taken to indicate that judgments of justice develop slowly and follow a stagelike progression, starting off with simple rules (e.g.

The moral, epistemic, and mindreading components of children's vigilance towards deception.

Vigilance towards deception is investigated in 3- to-5-year-old children: (i) In Study 1, children as young as 3 years of age prefer the testimony of a benevolent rather than of a malevolent communicator. (ii) In Study 2, only at the age of four do children show understanding of the falsity of a lie uttered by a communicator described as a liar. (iii) In Study 3, the ability to recognize a lie when the communicator is described as intending to deceive the child emerges around four and improves throughout the fifth and sixth year of life.