Self Comes to Mind

complex brains had long used to simulate their own body states. This would have had a clear and immediate advantage: rapid, energy-saving activation of the maps of certain body states, which were, in turn, associated with relevant past knowledge and cognitive strategies. Eventually the as-if system was applied to others and prevailed because of the equally obvious social advantages one could derive from knowing the body states of others, which are expressions of their mental states. In brief, I consider the as-if body loop system within each organism as the precursor to the operation of mirror neurons.
    As we shall see in Part III, the fact that the body of a given organism can be represented in the brain is essential for the creation of the self. But the brain’s representation of the body has another major implication: because we can depict our own body states, we can more easily simulate the equivalent body states of others. Subsequently, the connection we have established between our own body states and the significance they have acquired for us can be transferred to the simulated body states of others, at which point we can attribute a comparable significance to the simulation. The range of phenomena denoted by the word empathy owes a lot to this arrangement.
The Source of an Idea
     
    I first gleaned the possibility described above many years ago in an odd and memorable episode. One summer afternoon when I was at work in the lab, I had gotten up from my chair and was walking across my office when I suddenly thought of my colleague B. I had no particular reason to think of him—I had not seen him recently, I did not need to talk to him, I had not read about him, I had no plans whatsoever to see him—and yet there he was present in my mind, the full recipient of my attention. One thinks of other people all the time, but this was different, because the presence was unexpected and demanded an explanation. Why was I thinking of Dr. B now?
    Almost instantly a rapid succession of images told me what I needed to know. I mentally replayed my movements and realized that I had moved, for just a couple of moments, in a manner that was that of my colleague B. It had to do with the way I swung the arms and arched the legs. Now that I had discovered why I had been forced to think of him, I could picture his gait distinctly, in my mind’s eye. But the fine point is that the visual images I had formed were prompted—better still, shaped—by the image of my own muscles and bones’ adopting the distinctive motion patterns of my colleague B. In brief, I had just been walking like Dr. B; I had represented my animated skeletal frame in my own mind (technically, I had generated a somatosensory image); and finally I had recalled an appropriate visual counterpart for that particular musculoskeletal image, which turned out to be that of my colleague.
    As the identity of the intruder was revealed, I also gleaned something intriguing about the human brain: I could adopt the characteristic motion of someone else by pure chance. (Or nearly so: in a further replay, I remembered I had seen B walking by my office window sometime earlier. I had processed him with little or no attention, largely nonconsciously.) I could transform the represented motion into a corresponding visual image, and I could recover from memory the identity of a person or persons that would fit the description. All of this was testimony to the close interconnections among an actual motion of the body, the representations of that motion in musculoskeletal and visual terms, and the memories that can be evoked in relation to some aspect of those representations.
    This episode, enriched by additional observations and further reflection, made me realize how our connection to others occurs not just by visual images, language, and logical inference but also via something deeper in our flesh: the actions with which we can portray the movements of others. We can perform four-way translations among (1) actual movement, (2) somatosensory representations of movement, (3) visual representations of movement, and (4) memory. This episode would play a role in developing the notion of body simulation and its application in the as-if body loop.
    Good actors, of course, use these devices in spades, knowingly or not. The manner in which some of the greats channel certain personalities into their compositions draws on this power to represent others, visually and auditorily, and then