Although a large proportion of our lives are spent participating in social interactions, the investigation of the neural mechanisms supporting these interactions has largely been restricted to situations of social observation — that is, situations in which an individual observes a social stimulus without opportunity for interaction. In recent years, efforts have been made to develop a truly social, or ‘second-person’, neuroscientific approach to these investigations in which neural processes are examined within the context of a real-time reciprocal social interaction. These developments have helped to elucidate the behavioural and neural mechanisms of social interactions; however, further theoretical and methodological innovations are still needed. Findings to date suggest that the neural mechanisms supporting social interaction differ from those involved in social observation and highlight a role of the so-called ‘mentalizing network’ as important in this distinction. Taking social interaction seriously may also be particularly important for the advancement of the neuroscientific study of different psychiatric conditions.
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The authors thank D. Alkire, M.-L. Brandi, J. Lahnakoski, D. Moraczewski, K. Warnell and Y. Xiao for critical comments on the manuscript. The authors are also grateful to the referees for their valuable suggestions. E.R.’s contributions to this paper were supported in part by grants from the US National Institutes of Health (NIH; R01MH107441, R01MH112517 and P01 HD064653). L.S. was funded by a grant from the Max Planck Society for an Independent Max Planck Research Group. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or the Max Planck Society.
Nature Reviews Neuroscience thanks C. Frith, R. Montague and N. Sadato for their contribution to the peer review of this work.
The authors declare no competing interests.
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Redcay, E., Schilbach, L. Using second-person neuroscience to elucidate the mechanisms of social interaction. Nat Rev Neurosci 20, 495–505 (2019). https://doi.org/10.1038/s41583-019-0179-4
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