A Sensorimotor Network for the Bodily Self Francesca Ferri 1 , Francesca Frassinetti 2,3 , Martina Ardizzi 1 , Marcello Costantini 4,5 , and Vittorio Gallese 1,6 Abstract ■ Neuroscientists and philosophers, among others, have long questioned the contribution of bodily experience to the consti- tution of self-consciousness. Contemporary research answers this question by focusing on the notions of sense of agency and/or sense of ownership. Recently, however, it has been pro- posed that the bodily self might also be rooted in bodily motor experience, that is, in the experience of oneself as instantiating a bodily structure that enables a specific range of actions. In the current fMRI study, we tested this hypothesis by making par- ticipants undergo a hand laterality judgment task, which is known to be solved by simulating a motor rotation of oneʼs own hand. The stimulus to be judged was either the partici- pantʼs own hand or the hand of a stranger. We used this task to investigate whether mental rotation of pictures depicting oneʼs own hands leads to a different activation of the sensori- motor areas as compared with the mental rotation of pictures depicting anotherʼs hand. We revealed a neural network for the general representation of the bodily self encompassing the SMA and pre-SMA, the anterior insula, and the occipital cortex, bilaterally. Crucially, the representation of oneʼs own dominant hand turned out to be primarily confined to the left premotor cortex. Our data seem to support the existence of a sense of bodily self encased within the sensorimotor system. We propose that such a sensorimotor representation of the bodily self might help us to differentiate our own body from that of others. ■ INTRODUCTION In everyday life, we move, see, and feel our body and have no doubt that it is our own. Any experience of our body provides us with a variety of information related to it, such as our visual, tactile, and, more generally, physi- ological state. Besides the distinction between extero- ceptive, interoceptive, and proprioceptive awareness, what is the basic experience of our body as a bodily self? What enables us to implicitly distinguish our body from other human bodies (Ferri, Frassinetti, Costantini, & Gallese, 2011; Frassinetti, Ferri, Maini, Benassi, & Gallese, 2011; Frassinetti et al., 2009, 2010; Frassinetti, Maini, Romualdi, Galante, & Avanzi, 2008)? Recently, it has been proposed that the bodily self can be conceived as motor in nature (Gallese & Sinigaglia, 2010; Legrand, 2006), that is, based on the experience of our own body parts according to their motor potentialities, as they are repre- sented in a motor bodily format (see Gallese & Sinigaglia, 2011). Accordingly, Smith (2007) explained the concept of bodily self as follows: “The bodily self is a physical agent. Knowledge of oneself as bodily is fundamentally knowledge of oneself as agentive; such knowledge is grounded in both experience of oneself as instantiating a bodily structure that affords a limited range of actions, and experience of oneself as a physical agent that tries to perform a limited range of actions over time” (p. 4). The existence of such motor-experience-based repre- sentation of the bodily self has been investigated at the behavioral level in a previous study from our group (Ferri et al., 2011). In that study, right-handed participants underwent a laterality judgment task using rotated hand stimuli, where the hand to be judged could either be the participantʼs own hand or another personʼs hand. The results showed faster RTs when judging oneʼs right hand compared with all the other hand stimuli, regardless of the magnitude of the rotation. According to previous studies (Frassinetti et al., 2008, 2009, 2010), we named this effect “self-advantage. ” Moreover, Ferri and col- leagues (2011) found that self-advantage does not emerge when participants are asked to explicitly recognize the owner of the observed hand. On the basis of these empirical data, we argued in favor of the assumption that an implicit motor representation of the bodily self exists and that it might help us in distinguishing oneʼs own from othersʼ body, thus leading to the effect of self-advantage. In this fMRI study, we tested the hypothesis that the sensorimotor system plays a pivotal role in the implicit self/other distinction during the laterality judgment task and, more specifically, in the self-advantage for right hand in right-handed participants. We adopted the laterality judgment task because it is now accepted that, to perform it, one simulates a motor 1 University of Parma, 2 University of Bologna, 3 IRCCS - Istituto Scientifico di Castel Goffredo, Mantova, Italy, 4 University G. dʼAnnunzio, Chieti, Italy, 5 Foundation University G. dʼAnnunzio, Chieti, Italy, 6 Italian Institute of Technology © 2012 Massachusetts Institute of Technology Journal of Cognitive Neuroscience 24:7, pp. 1584–1595