Sounds of Hidden Agents: The Development of Causal Reasoning About Musical Sounds.

Listening to music activates representations of movement and social agents. Why? We test whether causal reasoning plays a role, and find that from childhood, people can intuitively reason about how musical sounds were generated, inferring the events and agents that caused the sounds. In Experiment 1 (N = 120, pre-registered), 6-year-old children and adults inferred the presence of an unobserved animate agent from hearing musical sounds, by integrating information from the sounds' timing with knowledge of the visual context.

Societal inferences from the physical world.

Moffett points to humans' use of physical markers to signal group identity as crucial to human society. We characterize the developmental and cognitive bases of this capacity, arguing that it is part of an early-emerging, intuitive which allows the inanimate world to encode rich social meaning about individuals' identities, and the values of the society as a whole.

Aesthetic Motivation Impacts Judgments of Others' Prosociality and Mental Life.

The ability to infer others' prosocial vs. antisocial behavioral tendencies from minimal information is core to social reasoning. Aesthetic motivation (the value or appreciation of aesthetic beauty) is linked with prosocial tendencies, raising the question of whether this factor is used in interpersonal reasoning and in the attribution of mental capacities.

Expectancy Effects Threaten the Inferential Validity of Synchrony-Prosociality Research.

Many studies argue that synchronized movement increases prosocial attitudes and behavior. We reviewed meta-analytic evidence that reported effects of synchrony may be driven by experimenter expectancy, leading to experimenter bias; and participant expectancy, otherwise known as placebo effects. We found that a majority of published studies do not adequately control for experimenter bias and that multiple independent replication attempts with added controls have failed to find the original effects.

Interpersonal utility and children's social inferences from shared preferences.

Similarity of behaviors or attributes is often used to infer social affiliation and prosociality. Does this reflect reasoning using a simple expectation of homophily, or more complex reasoning about shared utility? We addressed this question by examining the inferences children make from similar choices when this similarity does or does not cause competition over a zero-sum resource. Four- to six-year-olds (N = 204) saw two vignettes, each featuring three characters (a target plus two others) choosing between two types of resources.

The origins of dance: Characterizing the development of infants' earliest dance behavior.

Dance is a universal human behavior and a crucial component of human musicality. When and how does the motivation and tendency to move to music develop? How does this behavior change as a process of maturation and learning? We characterize infants' earliest dance behavior, leveraging parents' extensive at-home observations of their children. Parents of infants aged 0-24 months ( = 278, 82.

Hearing water temperature: Characterizing the development of nuanced perception of sound sources.

Without conscious thought, listeners link events in the world to sounds they hear. We study one surprising example: Adults can judge the temperature of water simply from hearing it being poured. We test the development of the ability to hear water temperature, with the goal of informing developmental theories regarding the origins and cognitive bases of nuanced sound source judgments.

Designing and detecting lies by reasoning about other agents.

How do people detect lies from the content of messages, and design lies that go undetected? Lying requires strategic reasoning about how others think and respond. We propose a unified framework underlying lie design and detection, formalized as recursive social reasoning. Senders design lies by inferring the likelihood the receiver detects potential lies; receivers detect lies by inferring if and how the sender would lie.

Acoustic regularities in infant-directed speech and song across cultures.

When interacting with infants, humans often alter their speech and song in ways thought to support communication. Theories of human child-rearing, informed by data on vocal signalling across species, predict that such alterations should appear globally. Here, we show acoustic differences between infant-directed and adult-directed vocalizations across cultures.

Triadic conflict "primitives" can be reduced to welfare trade-off ratios.

Pietraszewski proposes four triadic "primitives" for representing social groups. We argue that, despite surface differences, these triads can all be reduced to similar underlying welfare trade-off ratios, which are a better candidate for social group primitives. Welfare trade-off ratios also have limitations, however, and we suggest there are multiple computational strategies by which people recognize and reason about social groups.

Toward inclusive theories of the evolution of musicality.

We compare and contrast the 60 commentaries by 109 authors on the pair of target articles by Mehr et al. and ourselves. The commentators largely reject Mehr et al.

Starting small: exploring the origins of successor function knowledge.

Although most U. S. children can accurately count sets by 4 years of age, many fail to understand the structural analogy between counting and number - that adding 1 to a set corresponds to counting up 1 word in the count list.

Music as a coevolved system for social bonding.

Why do humans make music? Theories of the evolution of musicality have focused mainly on the value of music for specific adaptive contexts such as mate selection, parental care, coalition signaling, and group cohesion. Synthesizing and extending previous proposals, we argue that social bonding is an overarching function that unifies all of these theories, and that musicality enabled social bonding at larger scales than grooming and other bonding mechanisms available in ancestral primate societies. We combine cross-disciplinary evidence from archeology, anthropology, biology, musicology, psychology, and neuroscience into a unified framework that accounts for the biological and cultural evolution of music.

Babies know bad dancing when they see it: Older but not younger infants discriminate between synchronous and asynchronous audiovisual musical displays.

Movement to music is a universal human behavior, yet little is known about how observers perceive audiovisual synchrony in complex musical displays such as a person dancing to music, particularly during infancy and childhood. In the current study, we investigated how perception of musical audiovisual synchrony develops over the first year of life. We habituated infants to a video of a person dancing to music and subsequently presented videos in which the visual track was matched (synchronous) or mismatched (asynchronous) with the audio track.

Is the bias for function-based explanations culturally universal? Children from China endorse teleological explanations of natural phenomena.

Young children in Western cultures tend to endorse teleological (function-based) explanations broadly across many domains, even when scientifically unwarranted. For instance, in contrast to Western adults, they explicitly endorse the idea that mountains were created for climbing, just like hats were created for warmth. Is this bias a product of culture or a product of universal aspects of human cognition? In two studies, we explored whether adults and children in Mainland China, a highly secular, non-Western culture, show a bias for teleological explanations.

Two randomized trials provide no consistent evidence for nonmusical cognitive benefits of brief preschool music enrichment.

Young children regularly engage in musical activities, but the effects of early music education on children's cognitive development are unknown. While some studies have found associations between musical training in childhood and later nonmusical cognitive outcomes, few randomized controlled trials (RCTs) have been employed to assess causal effects of music lessons on child cognition and no clear pattern of results has emerged. We conducted two RCTs with preschool children investigating the cognitive effects of a brief series of music classes, as compared to a similar but non-musical form of arts instruction (visual arts classes, Experiment 1) or to a no-treatment control (Experiment 2).

Reasoning about 'irrational' actions: when intentional movements cannot be explained, the movements themselves are seen as the goal.

Infants and adults are thought to infer the goals of observed actions by calculating the actions' efficiency as a means to particular external effects, like reaching an object or location. However, many intentional actions lack an external effect or external goal (e.g.

Tracking replicability as a method of post-publication open evaluation.

Recent reports have suggested that many published results are unreliable. To increase the reliability and accuracy of published papers, multiple changes have been proposed, such as changes in statistical methods. We support such reforms.

Infant-directed speech drives social preferences in 5-month-old infants.

Adults across cultures speak to infants in a specific infant-directed manner. We asked whether infants use this manner of speech (infant- or adult-directed) to guide their subsequent visual preferences for social partners. We found that 5-month-old infants encode an individuals' use of infant-directed speech and adult-directed speech, and use this information to guide their subsequent visual preferences for individuals even after the speech behavior has ended.

Auditory-motor entrainment in vocal mimicking species: Additional ontogenetic and phylogenetic factors.

We have recently found robust evidence of motor entrainment to auditory stimuli in multiple species of non-human animal, all of which were capable of vocal mimicry. In contrast, the ability remained markedly absent in many closely related species incapable of vocal mimicry. This suggests that vocal mimicry may be a necessary precondition for entrainment.

Spontaneous motor entrainment to music in multiple vocal mimicking species.

The human capacity for music consists of certain core phenomena, including the tendency to entrain, or align movement, to an external auditory pulse [1-3]. This ability, fundamental both for music production and for coordinated dance, has been repeatedly highlighted as uniquely human [4-11]. However, it has recently been hypothesized that entrainment evolved as a by-product of vocal mimicry, generating the strong prediction that only vocal mimicking animals may be able to entrain [12, 13].