Research in the Mind and Development Lab focuses on social cognitive development, particularly the role of inference and explanation in social and causal reasoning. We're currently exploring how infants and children learn about other people, and how they understand the goals of others' actions.


Our work has also focused on music cognition, particularly the origins of our capacity to move in time with a beat. We often use music cognition as a window into novel aspects of social cognition, leveraging musical phenomena to answer questions about mental state inference.

Goal inference and action concepts
We can't see other people's goals directly - instead, we infer goals based on the movements people make. To make this inference, our minds use an implicit assumption: That people move efficiently toward the object they want. These goals are the primary way we encode and represent actions.

In this arm of the research program, we are exploring how we infer goals and represent actions, both as young children and as adults. We aim to account for our intuitive, early-developing understanding of actions like ritual and dance - which are universal and pervasive in human culture, but challenge existing frameworks for action understanding. In this work, we ask questions like:
  • How do we encode and represent dance and ritual actions?
  • What is the role of rational inference and explanation in action categorization?
  • How are our representations of action concepts structured (i.e. hierarchically)?
  • How do low-level, concrete goal inferences relate to high-level, abstract action categories?
In a recent paper, we found that when observing dance-like actions, adults infer that the actors' goal is to produce the movements for their own sake: Movements are seen as the intended outcome, not just a means to an end. We showed that observers infer these movement-based goals through a process of rational inference to the best explanation: When movements are clearly intentional, but cannot be explained in terms of any other goal (like an object or location), we conclude that the goal must have been to produce those movements for their own sake. The existence of movement-based goals stands in contrast to previous claims, showing that our representations of goals are far broader than previously believed.

We are currently exploring the development of movement-based goal inference in infants, asking whether imitation of movement-based goals is a particularly powerful cue to social affiliation (see below for more). We are also exploring the conceptual role of movement-based goals in adult action concepts. We have found strong evidence that movement-based goals serve as the conceptual foundation for abstract, lexicalized action categories, including dance and ritual.

Relevant Papers

Schachner, A. and Carey, S. (2013). Reasoning about 'irrational' actions: When intentional movements cannot be explained, the movements themselves are seen as the goal. Cognition, 129, 309-327. PDF, Supplementary Materials.
Schachner, A. and Carey, S. (in prep).The categorization of actions as dance and ritual depends on the rational inference that the movements are the goal.
Hannon, E., Schachner, A., & Levine, R.S. (in prep). Infants' understanding of dance: Detection of off-beat dancing to music by 10-month-old infants.

Relevant Conference Presentations

Schachner, A., & Carey, S. (2013). Exact imitation as a product of goal inference: When actions have irrelevant, arbitrary movements, implementing these movements is seen as part of the actors' goal. Talk presented at the Society for Research on Child Development, Seattle, WA.
Schachner, A., & Carey, S. (2012). Reasoning about 'irrational' actions: When intentional movements cannot be explained, the movements themselves are seen as the goal. Talk presented at Harvard-Yale Conference on Social Cognitive Development, Cambridge, MA.
Schachner, A., & Carey, S. (2011). Spontaneous goal inference without clear external goals: Dance is defined in terms of goals, not by features of the movement. Talk presented at the Society for Music Perception and Cognition, Rochester, NY.
Schachner, A., & Carey, S. (2011). Goal inference for 'irrational' actions: The movements themselves are seen as the goal. Poster presented at the 33rd Annual Meeting of the Cognitive Science Society, Boston, MA. PDF.
Inferring the causes of (music-like) sounds

Similar to tools or visual art, music is an artifact - something designed and produced by intentional actions. From early in development, understanding of material artifacts like tools depends on social cognition, particularly inferences about the artifacts' animate, intentional designer (Kelemen, 1999). Does the perception of auditory artifacts similarly rely on social cognition, even early in development? What cognitive mechanisms underlie this link to social cognition?


Infants' early development

In this line of research, we are exploring infants' reasoning about auditory artifacts, asking whether (and how) year-old infants infer that non-vocal sounds were caused by an animate agent. Using looking-time methods, we have found that year-old infants spontaneously infer whether agents caused the sounds they observe, an aspect of reasoning crucial to understanding sounds as artifacts. We are currently exploring the extent to which infants are able to rationally infer the causes of sounds they observe (i.e. Gopnik & Schulz, 2004), by combining their prior knowledge of the unique capacities of agents (i.e. self-propelled motion) with their understanding of physical causality (i.e. Gelman & Opfer, 2002). These studies lay the foundation for an exciting arm of our research program, characterizing children's early social reasoning about auditory artifacts like music, a ubiquitous and ancient feature of human culture.


Adults' mature representations

In a line of related studies with adults, we are investigating the specific hypothesis that people intuitively invoke living, animate agents as the explanation or cause of regular, orderly, patterned structure -- in music-like sounds, and also in other stimuli. Understanding how we reason about orderly stimuli is crucial for multiple psychological domains, including orderly objects (e.g. tools), orderly sounds (e.g. music), and order in nature (e.g. 'intelligent design'). In this work, we ask questions like:
  • Do all orderly stimuli cue agency?
  • Is this link the product of a simple association, or a rational inference that agents are the most likely cause?
  • How should we define "order", and how do adults represent this abstract concept?
Thus far, we find evidence that the link between order and agency is not simple, associative, or driven by low-level properties of the stimuli. Instead, the link between order and agency appears to be a product of high-level causal reasoning. In ongoing and future work, we aim to address broader questions regarding our intuitive causal explanations of orderly structure, and map out the cognitive mechanisms underlying the link between order and agency.

Relevant Papers

Schachner, A. (under revision). Causal inference accounts for the link between agents and order.
Schachner, A. & Kelemen, D. (in prep). 13-month-old infants infer the causal origins of musical sounds.

Relevant Conference Presentations

Schachner, A., Carey, S., & Kelemen, D. (2013). Inferring the causes of patterned sounds: Were those notes caused by an agent, or an inanimate force? Poster presented at the 8th Biennial Meeting of the Cognitive Development Society, Memphis, TN. PDF.
Social inferences from artifacts
Children grow up in environments saturated by artifacts - objects designed and produced through intentional action. These artifacts are crucial to our lives not only as tools, but also as an ever-present source of social information: Adults form quick and accurate judgments about another person's traits, interests, and social affiliations simply from the artifacts they own, wear and carry (e.g. Gosling, 2008; Richins, 1994).

With support from the NIH NICHD, we have begun exploring the developmental origins of social reasoning from artifacts. This research program has two primary goals:
  1. To characterize typically-developing children's ability to infer others' preferences, traits and social identities from their artifacts, including the types of cognitive processes (rational inference, simple heuristics) which underlie this social reasoning;
  2. To compare typically-developing children to children with Autism Spectrum Disorder, to identify deficits and delays which may contribute to the social difficulties of otherwise high-functioning children with ASD.
We have found that by four years of age, typically-developing children show a sophisticated ability to draw adult-like, rational conclusions about others' mutual interests based solely on their artifacts. This suggests that typically-developing children arrive at school privy to a rich and ubiquitous source of social information: The clothes, bags, tools and toys that others bring to the classroom. In ongoing work, we are investigating the range and types of social information children draw from artifacts, and examining developmental differences in ASD.

Relevant Papers

Schachner, A. and Kelemen, D. (in prep). Artifacts as windows into other minds: Pre-school children use artifacts to infer others' mutual interests.

Funding

2013 - 2016 - National Institute of Child Health and Human Development ($155,346.00)
1F32HD075570-01: Artifacts as windows into other minds: Social Reasoning in Typical and ASD Children.
Infant social cognition

Do infants use others' past behavior to choose preferred social partners? Do infants think of people as members of social groups, and expect members of a group to act similarly to one another?


Infant-directed speech as a social cue

Around the world, adults speak to infants in a specific manner termed infant-directed speech - with exaggerated emotion, slower speed, more repetition and higher pitch. Spontaneous use of infant-directed speech when interacting with infants appears to be an honest, informative signal of caregiver interest and ability. We asked whether infants use this informative social signal to guide their preferences for people, even after the speech behavior has ended. We found that even 5-month-old infants use this cue: After seeing someone speak in an infant-directed manner, 5-month-old infants preferred this person to a novel person; in contrast, after seeing someone speak in an adult-directed manner, infants preferred the novel individual - even after the speech behavior had ended. Thus, use of infant-directed speech may provide an informative social signal that allows infants to select appropriate social partners, focusing their attention on individuals who will provide optimal care and opportunity for learning.


Infants' understanding of social groups: Imitation as a social cue

Adults expect members of social groups to act alike, and imitate others to promote social affiliation. Do infants have similar expectations? In ongoing work, we and our collaborators find that year-old infants expect members of the same social group to produce the same the non-causal, dance-like actions (like jumping or sliding), but have no such expectations for actions that achieve a clear external goal (jumping that results in changing the color of a box). Imitation of non-causal actions appears to be more closely linked to social group membership than imitation of causal actions. Our work on goal inference provides a useful account of this finding (Schachner & Carey, 2013), and these data suggest that year-old infants have a nuanced understanding of the social implications of imitation of different types of actions. This lays the foundation for future work connecting goal inferences with the phenomena of imitation and reasoning about social groups.

Relevant Papers

Schachner, A., & Hannon, E. (2011). Infant-directed speech drives social preferences in 5-month-old infants. Developmental Psychology, 47, 19-25. PDF.
Trehub, S.E., Hannon, E.E., & Schachner, A. (2010). Perspectives on music and affect in the early years. In P.N. Juslin & J.A. Sloboda (Eds.), Handbook of music and emotion: Theory, research, applications. New York, NY: Oxford University Press. PDF.
Powell, L., Schachner, A., & Spelke, E. (in prep). Infants' generalization of causal and non-causal actions across social groups.

Relevant Conference Presentations

Powell, L., Schachner, A., & Spelke, E. (2014). Infants' generalization of causal and non-causal actions across social groups. Poster presented at the International Conference on Infant Studies, Berlin, Germany. PDF.
Schachner, A., & Hannon, E. (2008). The effect of infant-directed speech on early social preferences. Talk presented at the Harvard-Yale Conference on Social Cognitive Development, Cambridge, MA.
Schachner, A., & Hannon, E. (2007). Infant-directed Speech Modulates Subsequent Social Preferences in 5-month-old Infants. Poster presented at the International Conference on Infant Studies, Vancouver, Canada. PDF.
Schachner, A., & Hannon, E. (2007). The effects of infant-directed vocalizations on subsequent face preferences. Poster presented at the Cognitive Development Society, Santa Fe, NM. PDF.
The development of mental theories

As adults, we differentiate between the different domains of the natural world, including artifacts like tools and art, animate agents like people, and inanimate objects like mountains. We have rich, interconnected mental theories of each domain which allow us to reason about past origins and current properties, and make predictions about future states. How do these domain-specific mental theories develop in childhood?

Past work has characterized young children's understanding of the natural world, which in some ways appears notably different than adults'. In particular, young children in the US and UK often endorse purpose-based explanations even for non-living natural phenomena - they say mountains were created for hiking, just like hats were created for warmth. Is this bias innate and universal in young children, or is it a product of Western religious culture?

In two experimental studies involving 128 Chinese children and adults, we and our colleagues find evidence of a bias for purpose-based explanations of nature in Chinese children, and not in Chinese adults. This suggests that the bias for purpose-based explanations may be universal in early life, not solely a product of Western culture.

Relevant Papers

Schachner, A., Zhu, L., & Kelemen, D. (2017). Is the bias for function-based explanations culturally universal? Children from China endorse teleological explanations of natural phenomena. Journal of Experimental Child Psychology, 157 (2017), 29-48. PDF.
The origins and social consequences of entrainment

Why can humans universally move to a beat, while other primates cannot? How did this ability evolve, and how does it develop? Does moving in synchrony with others promote prosocial attitudes and behavior?


Evolutionary origins of entrainment

In past work, we and our colleagues tested the frequent claim that the ability to entrain, or move along with an external auditory pulse, is uniquely human. We showed that two vocal mimicking nonhuman animals (parrots) were able to entrain to music, spontaneously producing synchronized movements resembling human dance. Next, we tested the hypothesis that entrainment evolved as a by-product of vocal mimicry. In particular, we examined an extensive comparative data set from a global video database, including hundreds of species both capable and incapable of vocal mimicry. Despite the higher representation of vocal non-mimics in the database and comparable exposure of mimics and nonmimics to humans and music, only vocal mimics showed evidence of entrainment. Thus, entrainment is not unique to humans, and the distribution of entrainment across species supports the hypothesis that entrainment evolved as a by-product of selection for vocal mimicry.


Social consequences of entrainment: The role of synchrony

In related work, we have asked whether there are social benefits to auditory-motor entrainment, perhaps explaining why humans so often engage in entrainment to sound while other species rarely do. Many studies have claimed that moving in synchrony with other people results in higher prosocial behavior and prosocial attitudes, including greater cooperation and conformity. However, in our work we have failed to replicate several of these effects with both exact and conceptual replications when additional necessary controls are instituted. In particular, we do not find social effects of synchrony when experimenters are kept unaware of participants' experimental condition, preventing possible experimenter bias; or when the effects of synchrony are isolated from other factors. This work provides important methodological recommendations to ensure clarity of findings in this literature, and suggests that the social effects of synchrony may result from having engaged in cooperative behavior toward a shared goal (i.e. the goal of coordinating one's movements), not due to synchrony per se.

Relevant Papers

Schachner, A. (2013). The origins of human and avian auditory-motor entrainment. In A. Wessel, R. Menzel, & G. Tembrock (Eds.), Quo Vadis, Behavioural Biology? Past, Present, and Future of an Evolving Science. Nova Acta Leopoldina N.F. 111 (380), 243-253. PDF.
Schachner, A. (2012). If horses entrain, don't entirely reject vocal learning: An experience-based vocal learning hypothesis. Empirical Musicology Review, 7 (3-4), 157-159. PDF.
Schachner, A. (2010). Auditory-motor entrainment in vocal-mimicking species: Additional ontogenetic and phylogenetic factors. Communicative & Integrative Biology, 3 (3), 1-4. PDF.
Schachner, A., Brady, T. F., Pepperberg, I.M., & Hauser, M.D. (2009). Spontaneous motor entrainment to music in multiple vocal-mimicking species. Current Biology, 19, 831-836. PDF. Supplement. Table. Video 1. Video2. YouTube Videos (zip file).

Relevant Conference Presentations

Schachner, A. & Garvin, L. (2010). Does synchrony really affect social variables? Effects on cooperation, conformity may not be robust. Poster presented at the International Conference on Music Perception and Cognition, Seattle, WA. PDF.
Schachner, A., Brady, T.F., Pepperberg, I., & Hauser, M. (2009). Entrainment to music requires vocal mimicry: Evidence from non-human animals and human individual differences. Talk presented at the Berlin Behavioral Biology Symposium, Berlin, Germany.
Schachner, A., Brady, T.F., & Hauser, M.D. (2009). Good vocal mimics are also good entrainers: Individual differences suggest a shared mechanism for entrainment and vocal mimicry. Poster presented at the Society for Music Perception and Cognition, Indianapolis, IN. PDF.
Schachner, A., Brady, T. F., Pepperberg, I., & Hauser, M. (2008). Spontaneous entrainment to auditory rhythms in vocal-mimicking bird species. Talk presented at Music, Language and the Mind, Somerville, MA.
Schachner, A., Brady, T. F., Pepperberg, I., & Hauser, M. (2008). Spontaneous entrainment to auditory rhythms in vocal-learning bird species. Poster presented at The Neurosciences and Music III, Montreal, Canada. PDF.
Meta-research: Increasing replicability in science
There is extensive evidence that a large percentage of published findings are not reliable (in psychology as well as multiple other fields), leading to difficulty drawing conclusions and accurately estimating effect sizes from the published scientific record. We believe strongly that the replicability of published findings in the scientific literature must be improved.


In this line of meta-research, we ask questions like: How can we increase the importance of replicability, and incentivize replication? How can we promote a nuanced understanding of replication data, and use meta-analysis to avoid over-weighting non-replications? We also do our best to present our own replications and non-replications at conferences and in journals.


One step toward incentivizing replications that we and our colleagues have proposed is a system for post-publication replication tracking, designed to improve the reliability and accuracy of published research. We believe that the incentive structure of scientific publishing must change for the quality of data and scientific conclusions to be improved. Under the current system, the quality of individual scientists is often judged on the basis of their number of publications and citations, with journals similarly judged via numbers of citations. Neither of these measures takes into account the replicability of the published findings, as false or controversial results are often particularly widely cited. We propose tracking replications as a means of post-publication evaluation, both to help researchers identify reliable findings and to incentivize the publication of reliable results. In particular, we propose creating a replicability score for each journal to go along with their impact factor, hopefully incentivizing the publishing of not only exciting research but replicable research as well.


We have presented - and published - research that examines the reliability of important areas of research. In particular, we have presented work showing that when experimenters are blind to condition, effects of synchrony on social variables are not robust. We have also shown, with our collaborators, that at least some kinds of preschool music enrichment provide no consistent benefits to nonmusical cognitive tasks. In both cases, we presented and/or published this data to ensure the completeness of the scientific record on these issues.

Relevant Papers

Mehr, S., Schachner, A., Katz, R., & Spelke, E. (2013). Two randomized trials provide no consistent evidence for nonmusical cognitive benefits of brief preschool music enrichment. PLOS ONE, 8(12), e82007. PDF.
Hartshorne, J.K., & Schachner, A. (2012). Tracking replicability as a method of post-publication open evaluation. Frontiers in Computational Neuroscience, 6 (8), 1-14. PDF.

Relevant Conference Presentations

Schachner, A. (2015).Tracking Replicability: An Approach to Assess Reproducibility Following Publication. Talk to be presented at the annual meeting on Experimental Biology, Boston, MA.
Mehr, S., Schachner, A., Katz, R., & Spelke, E. (2013). Inconsistent evidence for nonmusical cognitive benefits of preschool music enrichment. Poster presented at the 25th Annual Convention of the Association for Psychological Science, Washington, DC. PDF.
Schachner, A. & Garvin, L. (2010). Does synchrony really affect social variables? Effects on cooperation, conformity may not be robust. Poster presented at the International Conference on Music Perception and Cognition, Seattle, WA. PDF.