My research explores the intersection of social cognition with music cognition, movement and action.
I aim to shed light on novel elements of social cognition by leveraging the phenomena of music and dance; for example, I am working to expand our understanding of goal inferences to explain how we reason about actions like dance, ritual and exercise. I also aim to understand how our perception of music and dance depends on social cognitive representations, even early in development.
In addition, I am interested in the developmental and evolutionary origins of the human music capacity, particularly the origins and social consequences of our ability to entrain, or move in synchrony with an auditory beat.
I use a range of methods and populations, including experimental methods from both cognitive and social psychology to study adults; developmental methods, such as looking-time measures, to study human cognition prior to extensive experience; and cross-species comparative methods to get at evolutionary questions.
The existing literature on action understanding has explored how we infer another persons' goal based on the particular movements they make. In my work, I've been expanding these ideas to explore our understanding of actions in which the movements can't be construed as the efficient way to achieve any external goal - for example, dance-like actions, where a person doesn't seem to be trying to modify the environment in any way. Contrary to the prediction of existing action understanding literature, I've found that people still attribute goals to these actions - in particular, they infer that the person's goal is simply to produce the movements themselves.
This inference causes us to make different predictions about the person's next actions, and, interestingly, is driven by the extent to which the actions are inefficient as ways to accomplish other hypothesized goals (rather than by various perceptual features and simpler factors). This pattern of inference fits with a Bayesian model of goal inference (Baker, Saxe & Tenenbaum, 2009), so long as the goal of producing the movements exists as a hypothesis.
In a related line of studies, I've shown that that this goal inference is conceptually related to higher-level action concepts, including dance, ritual and exercise.
Papers
Schachner, A. & Carey, S. (in prep). Goal inference for 'irrational' actions: Producing the movements is seen as the goal.
Schachner, A. & Carey, S. (in prep). The essence of our concepts of dance, exercise and ritual: The rational inference that the movements are the goal.
Humans around the world are able to entrain, or align their movements, to an external auditory pulse. This ability has been repeatedly highlighted as uniquely human; however, in recent years it has 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.
We provide comparative data demonstrating the existence of two proficient vocal mimicking nonhuman animals (parrots) that entrain to music, spontaneously producing synchronized movements resembling human dance. We also provide an extensive comparative data set from a global video database, systematically analyzed for evidence of entrainment in hundreds of species both capable and incapable of vocal mimicry.
Despite the higher representation of vocal nonmimics in the database, and comparable exposure of mimics and nonmimics to humans and music, only vocal mimics showed evidence of entrainment, with the ability remaining markedly absent in many closely related species incapable of vocal mimicry. These data suggest that vocal mimicry may be a necessary precondition for entrainment, and that our capacity to entrain may have evolved in part as a byproduct of selection for vocal imitation.
Sample videos of birds entrained to music
Download the YouTube videos analyzed in the Current Biology paper
Papers
Schachner, A. (2010). 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., Bd. 111, Nr. 380). Paper.
Schachner, A. (2010). Auditory-motor entrainment in vocal-mimicking species: Additional ontogenetic and phylogenetic factors. Communicative & Integrative Biology, 3 (3), 1-4. Paper.
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. Paper. Supplement. doi:10.1016/j.cub.2009.03.061
Adults across cultures speak to infants in a specific infant-directed manner, often termed 'musical speech' for its exaggerated prosody and slower, repetitive structure. In a chapter on early development, colleagues and I aimed to integrate the literature on infant-directed speech, music and vocal affect.
We also investigated 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. We suggest that use of infant-directed speech may act as an effective cue for infants to select appropriate social partners, allowing infants to focus their attention on individuals who will provide optimal care and opportunity for learning.
Papers
Schachner, A., & Hannon, E. (2011). Infant-directed speech drives social preferences in 5-month-old infants. Developmental Psychology, 47,19-25. Paper. doi: doi:10.1037/a0020740
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. Chapter.