Self Comes to Mind

execution of a certain movement to inform visual structures of the likely consequence of that forthcoming movement in terms of spatial displacement. For example, when our eyes are about to move toward an object at the periphery of our vision, the visual region of the brain is forewarned of the impending movement and ready to smooth the transition to the new object without creating a blur. In other words, the visual region is allowed to anticipate the consequence of the movement. 8 Simulating a body state without actually producing it would reduce processing time and save energy. The as-if body loop hypothesis entails that the brain structures in charge of triggering a particular emotion be able to connect to the structures in which the body state corresponding to the emotion would be mapped. For example, the amygdala (a triggering site for fear) and the ventromedial prefrontal cortex (a triggering site for compassion) would have to connect to somatosensing regions, areas such as the insular cortex, SII, SI, and the somatosensory association cortices, where ongoing body states are continuously processed. Such connections exist, thereby rendering possible the implementation of the as-if body loop mechanism.
    In recent years, more support for this hypothesis has come from several sources, one of which is a series of experiments by Giacomo Rizzolatti and his colleagues. In these experiments, which made use of electrodes implanted in the brains of monkeys, a monkey would watch an investigator perform a variety of actions. When a monkey saw the investigator move his hand, neurons in the monkey’s brain regions related to its own hand movements became active, “as if” the monkey, rather than the investigator, were performing the action. But in reality the monkey remained immobile. The authors referred to the neurons that behaved in this manner as mirror neurons. 9
    So-called mirror neurons are, in effect, the ultimate as-if body device. The network in which those neurons are embedded achieves conceptually what I hypothesized as the as-if body loop system: the simulation, in the brain’s body maps, of a body state that is not actually taking place in the organism. The fact that the body state simulated by mirror neurons is not the subject’s body state amplifies the power of this functional resemblance. If a complex brain can simulate someone else’s body state, one assumes that it would be able to simulate its own body states. A state that has already occurred in the organism should be easier to simulate since it has already been mapped by precisely the same somatosensing structures that are now responsible for simulating it. I suggest that the as-if system applied to others would not have developed had there not first been an as-if system applied to the brain’s own organism.
    The nature of the brain structures involved in the process reinforces the suggestive functional resemblance between the as-if body loop and the operation of mirror neurons. For the as-if body loop, I hypothesized that neurons in areas engaging emotion, such as the premotor-prefrontal cortex (in the case of compassion) and the amygdala (in the case of fear) would activate regions that normally map the state of the body and, in turn, move it to action. In humans such regions include the somatomotor complex in the Rolandic and parietal opercula as well as the insular cortex. All of these regions have a dual somatomotor role: they can hold a map of the body state, a sensory role, and they can participate in an action as well. By and large, this is what the neurophysiological experiments with monkeys uncovered. This is also consonant with human studies using magnetoencephalography 10 and functional neuroimaging. 11 Our own studies based on neurological lesions point in the same direction. 12
    Explanations of the existence of mirror neurons have emphasized the role that such neurons can play in allowing us to understand the actions of others by placing ourselves in a comparable body state. As we witness an action in another, our body-sensing brain adopts the body state we would assume were we ourselves moving, and it does so, in all probability, not by passive sensory patterns but by a preactivation of motor structures—ready for action but not allowed to act yet—and in some cases by actual motor activation.
    How did such a complex physiological system evolve? I suspect that the system developed from an earlier as-if body loop system, which