At the beginning of this paper I asked which brain mechanisms underlie pre-reflective representations of the bodily self and social cognition. ES, based on motor resonance, substantially contributes to the representation of the bodily self and social cognition. However, a unified theory of the neural basis of these target phenomena cannot assign a primary role to motor resonance. I have argued that multisensory spatial coding is at least of equal importance and probably more basic than ES in contributing to several key aspects of the bodily self and social cognition.
Specifically, I have argued that:
(1) Social cognition and the bodily self depend on multisensory spatial coding, which is distinct from motor resonance. Thus, motor resonance may be a necessary but insufficiently “primary” brain mechanism of social cognition and the bodily self (cf. section 1, 2).
(2) The brain networks underlying social cognition and the bodily self largely overlap. Specific functional associations exist (a) between motor resonance and body ownership/agency and (b) between multisensory spatial coding and self-location/the first-person perspective (cf. section 2).
(3) The vestibular system, i.e., the sensory system encoding head motion and gravity, might provide unique information used for multisensory spatial coding that relates the bodily self to other individuals and the external world. This is further suggested by the large overlap existing between the human vestibular cortex and the brain networks underlying the bodily self and social cognition (cf. section 3).
A unifying theory of pre-reflective brain mechanisms of the bodily self and social cognition must be able to account for the empirical evidence reviewed here; and it seems that such a theory cannot exclusively depend on motor resonance. Multisensory spatial coding, motor mechanisms, but also representations of the process of attention appear highly relevant to bodily self and social cognition.
I agree with Gallese & Cuccio (this collection, pp. 3–7) that cognitive neuroscience cannot fully explore these exciting topics by limiting itself to a specific neuroimaging method, such as functional magnetic resonance imaging. Instead, we should exploit multi-method approaches in search for correlative and causal evidence relating brain function and anatomy to the phenomenology of the bodily self and social cognition. The body, but also the spatial representation of the world around us, are relevant to understanding brain function, and when taken into account can lead to novel approaches to phenomenal analysis of subjective experience. But we should be careful in assigning priority to a single brain mechanism when aiming to explain the human self and intersubjectivity. Scrutiny and dialogue at the intersection of philosophy of mind and cognitive neuroscience are necessary in order to advance our understanding of the nature of the human mind.
Acknowledgments
I thank Thomas Metzinger, Jennifer Windt, and two anonymous reviewers for constructive comments on an earlier version of this commentary.