Consciousness and the Social Brain

emotions, motivations, and thoughts. We conceive of a mind as a thing that resides here or there, in a particular location. A perceptual model of a mind includes, among its many components, a spatial location assigned to the model. It is true perception in the sense that the perceived properties have a perceived location to form a perceived object. This spatial embodiment is especially apparent in the out-of-body experience. In that state, the machinery has been disrupted and the brain computes and assigns an incorrect location to one’s own mind. My thoughts, my emotions, my motivations, my intentions—these are all suddenly located in the upper corner of the room. Or seem to be.
    This spatial embodiment of a mind is evidently a function of an expert system. In the now classic experiment by Blanke and colleagues, 11 disruption of the TPJ in the right hemisphere caused an out-of-body experience. Vesting a mind with a location, with a spatial structure, may be a part of the building of models carried out by the TPJ and perhaps other areas in the social cognition network.
    We don’t normally think of social perception as being literally like sensory perception. But in this sense it is: we construct a set of properties and bind them to a spatial location. This ability to compute a spatial embodiment when constructing a model of a mind solves one of the long-standing difficulties of simulation theory. You know whether the perceived mental states are yours, or John’s, or Susan’s, in the same way that you know whether the color blue belongs to your shirt, to John’s shirt, to Susan’s shirt, or to the car at the curb. You keep track of it by spatial assignment. You perceive the thoughts and emotions to be emanating spatially from this person, that person, or from yourself. A model of a mind comes with a spatial assignment. Simulation theory by itself cannot solve the problem, but combined with a computed model of a mind, complete with a computed spatial structure, that particular problem disappears.
Difficulty 2: Solving Circularity

    Before Brain A can mirror the state of Brain B, it needs to know what state to mirror. Brain A needs a mechanism that generates hypotheses about the state of Brain B. What generates the initial hypotheses?
    In the hybrid model proposed here, specialized areas generate the hypotheses about other people’s mind states. Those hypotheses are further refined by simulation. If you look at another person grasping a pen, first visual information enters the eye, percolates through the visual system, and reaches the biological motion neurons in the STS. This expert system in the STS uses incoming visual information to categorize the action. The biological motion detectors in the STS are,essentially, computing a hypothesis about the nature of the action. The STS can then drive the mirror neurons that simulate the action. The mirror neurons essentially compute the details of how you would perform the action. The simulation provides nuanced information about the action. In this way, your understanding of the other person’s action is built up by a dialogue between an expert system and a mirror-neuron system. The likely dependence of mirror neurons on an interaction with the STS has been emphasized before. 7
    In the hybrid system, mirror neurons are not rivals to the theory that social perception is emphasized in specialized regions such as the TPJ and STS. Instead, the two mechanisms for social perception could operate in a cooperative fashion. In this proposed scheme, the mirror-neuron system is an extended loop adding to and enhancing the machinery that constructs models of minds.
Simulation of One’s Own Mind: The Resonance Loop

    In the previous section I discussed the possibility that social perception includes two interrelated processes: constructing a model of a mind, and elaborating on that model through brain-wide simulation. The separation between these two processes is probably artificial or at least less categorical than the labels suggest. Think how much more complicated, in a recursive, loop-the-loop way, these processes become when applied to oneself.
    Suppose that you are modeling your own mind state. Suppose your self model includes the hypothesis that you are angry right now. To enhance that hypothesis, to enrich the details through simulation, the machinery that constructs your self model contacts and uses your emotion-generating machinery. The state of anger is implemented