Chapter 3: Body Image, Out-of-Body Experiences, and the Virtual Self
You are never in direct contact with your own body. What you feel in the rubber-hand illusion, what AZ feels, or what Philip feels when his left arm is “plugged in” is exactly the same as what you feel when you attend to the sensation of your hands holding this book right now or to the feeling of pressure and resistance when you lean back in your chair. What you experience is not reality but virtual reality, a possibility. Strictly speaking, and on the level of conscious experience alone, you live your life in a virtual body and not in a real one.
Yes, everything we experience is virtual. We never experience reality directly, but only the brain simulation.
So what is the self in this simulation? The self is a complex construction of several parts, all of which usually stays together, but might come apart. The components are:
- Model of the physical body: the arms, the legs, the joint-angles, the head...
- Model of the inside of the physical body (interoceptive self): temperature, fullness, heartrate...
- Model of the viewpoint: a "camera" in the model of the world. It is usually sitting between the eyes of the physical body model, but it can move around.
- Others.
We know more: A seeing self also is not necessary. You can shut the windows in front of the little man behind your eyes by closing your eyelids. The seeing self disappears; the Ego remains. You can be a robust, conscious self even if you are emotionally flat, if you do not engage in acts of will, and also in the absence of thought. Emotions, will, and thoughts are not necessary to the fundamental sense of selfhood. Every meditator (remember chapter 1) can confirm that you may settle into a calm, emotionally neutral state, deeply relaxed and widely alert, a state of pure observation, without any thought, while a certain elementary form of bodily self-consciousness remains. Let us call this “selfhood-as-embodiment.”
Minimal self-consciousness is not control, but what makes control possible.
Metzinger guesses that this minimal self-consciousness is made of these parts:
- A model of spacetime.
- A point in this spacetime model, representing a personal viewpoint.
- A model of the body (usually humanoid) centered around the viewpoint.
The mental action of expanding your knowledge about the world, for example, by selecting what you will know, while at the same time excluding what you will, for now, ignore. What this adds is a strong first-person perspective, the experience of being directed at an object.
In more concrete terms, if the self-model can predict what would be enlarged in, and what would be removed from, the global workspace, then the self-model has control of its attention, and that is epistemic control.
In more concrete terms, even if you are lost in a total void dreamland, cannot see or hear, and unable to move your dream body, you can still direct your attention around your dream body, from the head, to the back, to the legs. This makes you into a minimal subject.
As an example of consciousness-engineering, we can imagine how to make a self-conscious airplane. The first step is to install a flight simulator, which would contain a model of spacetime, a model of the plane itself, and a camera-point somewhere inside the cockpit. That would give us a minimally self-conscious plane.
To make the plane into a minimal subject, install a self-attention control software. This thing would bring parts of the plane's self-model into focus on a "global workspace" buffer. It can fill it with info on the left alieron, or the right flapper, or something else.
OBE and autoscopy
My vision was generally poor during OBE experiences, as would be expected in a dark bedroom at night. When I realized I was unable to flip the light switch in front of which I found myself standing in my OBE state, I became extremely nervous. In order not to ruin everything and lose a precious opportunity for experiments, I decided to stay put until I had calmed down. Then I attempted to walk to the open window, but instead found my- self smoothly gliding there, arriving almost instantaneously. I carefully touched the wooden frame, running my hands over it. Tactile sensations were clear but different—that is, the sensation of relative warmth or cold was absent. I leaped through the window and went upward in a spiral. A further phenomenological feature accompanied this experience—the compulsive urge to visualize the headline in the local newspapers: “WAS IT ATTEMPTED SUICIDE OR AN EXTREME CASE OF SOMNAMBULISM ? PHILOSOPHY STUDENT DROPS TO HIS DEATH AFTER SLEEPWALKING OUT THE WINDOW.” A bit later, I was lying on top of my physical body in bed again, from which I rose in a controlled fashion, for the second time now. I tried to fly to a friend’s house in Frankfurt, eighty-five kilometers away, where I intended to try to make some verifiable observations. Just by concentrating on my destination, I was torn forward at great speed, through the wall of my bedroom, and immediately lost consciousness. As I came to, half-locked into my physical body, I felt my clarity decreasing and decided to exit my body one last time.
The records are so fun to read! I'll quote a few more.
my body was lying there in some kind of paralysis. Simultaneously, I found I could pull my hands out of my physical hands, as if the latter were just a stiff pair of gloves. The process of detachment started at the finger- tips, in a way that could be felt clearly, with a perceptible sound, a kind of crackling. This was precisely the movement I had in- tended to carry out with my physical hands. With this, I detached from my body and floated out of it head first, attaining an upright position, as if I were almost weightless. Nevertheless, I had a body, consisting of real limbs. You have certainly seen how elegantly a jellyfish moves through the water. I could now move around with the same ease.
I lay down horizontally in the air and floated across the bed, like a swimmer who has pushed himself off the edge of a swimming pool. A delightful feeling of liberation arose within me. But soon I was seized by the ancient fear common to all living creatures—the fear of losing my physical body. It sufficed to drive me back into my body.
As noted, the sleep paralysis Waelti describes is not a necessary condition for OBEs. They frequently occur following accidents, in combat situations, or during extreme sports—for instance in high-altitude climbers or marathon runners:
A Scottish woman wrote that, when she was 32 years old, she had an OBE while training for a marathon. “After running approximately 12–13 miles . . . I started to feel as if I wasn’t looking through my eyes but from somewhere else. . . . I felt as if some- thing was leaving my body, and although I was still running along looking at the scenery, I was looking at myself running as well. My ‘soul’ or whatever, was floating somewhere above my body high enough up to see the tops of the trees and the small hills.”
OBE experiences are quite common:
Various studies show that between 8 and 15 percent of people in the general population have had at least one OBE. There are much higher incidences in certain groups of people, such as students (25 percent), paranormal believers (49 percent), and schizophrenics (42 percent); there are also OBEs of neurological origin, as in epileptics.
OBE is similar to some other phenomena:
- autoscopy: patients see their own body outside, but they do not identify with it and don’t have the feeling that they are “in” this illusory body.
- heautoscopy: things may sometimes go back and forth, and the patient doesn’t know which body he is in right now.
- feeling of a presence: a second illusory body is only felt (but not seen).
I have always believed that OBEs are important for any solid, empirically grounded theory of self-consciousness. But I had given up on them long ago; there was just too little substantial research, not enough progress over decades, and most of the books on OBEs merely seemed to push metaphysical agendas and ideologies. This changed in 2002
when it was discovered that electrode stimulation at certain brain areas consistently induced OBE:
Initial stimulations induced feelings that the patient described as “sinking into the bed” or “falling from a height.” Increasing the current amplitude to 3.5 milliamperes led her to report, “I see myself lying in bed, from above, but I see only my legs and lower trunk.” Further stimulations also induced an instantaneous feeling of “lightness” and of “floating” about six feet above the bed. Often she felt as though she were just below the ceiling and legless.
How to interpret OBE and related phenomena?
When I first met Blackmore, in Tübingen in 1985, and told her about several out-of-body experiences of my own, she kept asking me to describe, painstakingly, how I moved during these episodes. Not until then did I realize that when I moved around my bedroom at night in the OBE state, it was not in a smooth, continuous path, as in real-life walking or as one might fly in a dream. Instead, I moved in “jumps”—say, from one window to the next. Blackmore has hypothesized that during OBEs we move in discrete shifts, from one salient point in our cognitive map to the next. The shifts take place in an internal model of our environment—a coarse-grained internal simulation of landmarks in settings with which we are familiar. Her general idea is that the OBE is a conscious simulation of the world—spatially organized from a third-person perspective and including a realistic representation of one’s own body— and it is highly realistic because we do not recognize it as a simulation.
The fact that during an OBE, people experience two selves: a body-self, and an astral-self, indicates two separate components of the self-model.
- The "body-self" is the self-model of the body: where the legs go, where the arms go, where the head goes, as a lump of jointed meat and bones occupying a volume in space.
- The "astral-self" is a separate self-model. It is basically a mentally simulated ghosty camera floating in mentally simulated space, the self-visual-standpoint. Around this camera, there is a ghosty body that has no weight, experiences no gravity, and cannot collide with anything, but it is still a body, with hands and legs that you can bend. The ghosty camera is perched between the eyes of the body-self, usually.
- Most of the times, the astral body and the physical body are coincident, but during OBE, they aren't.
It is a lot less bizarre when one thinks about memories, or imaginations. When you relive a memory, or imagine what you'd do in a story, often you are seeing yourself from a third-person perspective, as if you are having an OBE.
So, what is the philosophical significance of OBE? It shows that there are different parts of the self-model: the body-self, the viewpoint-self. They usually are linked together, but when they come apart, our sense of self always follows the viewpoint-self. That is, our "locus of identity" is the viewpoint-self.
Another reason the OBE is interesting from a philosophical perspective is that it is the best known state of consciousness in which two self-models are active at the same time. To be sure, only one of them is the “locus of identity,” the place where the agent (in philosophy, an entity that acts) resides. The other self-model—that of the physical body lying, say, on the bed below—is not, strictly speaking, a self-model, because it does not function as the origin of the first-person perspective. This second self-model is not a subject model. It is not the place from which you direct your attention. On the other hand, it is still your own body that you are looking at. You recognize it as your own, but now it is not the body as subject, as the locus of knowledge, agency, and conscious experience. That is exactly what the Ego is. These observations are interesting because they allow us to distinguish different functional layers in the conscious human self.
Rubber-hand and whole-body illusions
The rubber-hand illusion is too famous for me to summarize. And if it can be done with a hand, it can be done for the entire body. In Video ergo sum: manipulating bodily self-consciousness (2007), the authors reported an experiment for just that, using VR.
We found that during multisensory conflict, participants felt as if a virtual body seen in front of them was their own body and mislocalized themselves toward the virtual body, to a position outside their bodily borders. Our results indicate that spatial unity and bodily self-consciousness can be studied experimentally and are based on multisensory and cognitive processing of bodily information.
Kinda like this painting La reproduction interdite (1937)
The general feeling of rubber-hand illusion is like "moving the spiritual hand out of the flesh glove into the rubber glove".
The interpretation is this: the brain, by combining visual and tactile information, updated its body model, to identify the visually seen rubber hand with the right hand of the body model. The illusion is ruined when one tries to move the fingers, because the rubber hand would not move, snapping the right hand of the body model back to the actual right hand.
Telepresence robots
Ideally, a human operator would identify his or her own body with that of the slave robot, achieving this with the help of the virtual body, which functions as an interface. Again, nature did just that millions of years ago: Like a virtual body, the phenomenal self-model is an advanced interface designed to appropriate and control a body. Whereas in the case of the virtual body, the slave robot may be thousands of miles away, in the case of the Ego, the target system and the simulating system are identical: The conscious experience of being a subject arises when a single organism learns to enslave itself.
Phantom limbs
Philip rotated his body, shifting his shoulder, to “insert” his lifeless phantom into the box. Then he put his right hand on the other side of the mirror and attempted to make synchronous movements. As he gazed into the mirror, he gasped and then cried out, “Oh, my God! Oh, my God, doctor! This is unbelievable. It’s mind-boggling!” He was jumping up and down like a kid. “My left arm is plugged in again. It’s as if I’m in the past. All these memories from years ago are flooding back into my mind. I can move my arm again. I can feel my elbow moving, my wrist moving. It’s all moving again.”
In Philip's mind, there is a model of the human body of Philip, which includes the nonexistent left arm. Since there is no actual left arm, there is no sensory input about it, and so the model of the left arm remains static, never updating its shape. This is felt as an uncomfortable paralysis.
However, as soon as Philip does the mirror trick, there is visual input about the left arm, and the model of the left arm updates. This model update is felt as a real turning of the left arm.
Somatoparaphrenia
Metzinger doesn't speak of it, but there is an opposite to phantom limbs: somatoparaphrenia,
where one denies ownership of a limb or an entire side of one's body. Even if provided with undeniable proof that the limb belongs to and is attached to their own body, the patient produces elaborate confabulations about whose limb it really is or how the limb ended up on their body.
The confabulations can be funny. I quote Somatoparaphrenia: a body delusion. A review of the neuropsychological literature (2009):
- A woman laying in the bed on the left side of the patient’s body.
- A nest of hands in his bed. Two months later the patient asked hands to be removed, and put in a bag with the remaining ones. The left hand was not the “right” one. New hand more voluminous, heavier, and fleshier, old one smaller and thinner.
- Patient hit her estranged L-ULi, and scratched her L-LLi, identiWed as “the doctor’s leg”. Hand ownership acknowledged with vision prevented, and tactile exploration by the R hand being used. In front of a mirror, with direct vision prevented, ownership of the L hand immediately acknowledged. With both mirror and direct vision deWcit unchanged
- Hand belonging to another Pt (forgotten in the ambulance).
- Three left arms: one of the Pt, one of his niece, the 3rd crossed over his chest
- Disownership of the hand and forearm. Pt lost her hand as a girl. Pt found the hand in the room and sewed it on.
- In darkness, presence of the Pt’s sister on the left side of her body, for three nights a welcome presence, as the Pt was less alone. From the fourth night, the Pt reported that there was not enough space in the bed for two, became angry with her sister, and finally repeatedly bit the sister’s right arm (actually, the Pt’s left arm).
I can't resist quoting some more bizarre confabulations. This is from Anosognosia and major depression in 2 patients with cerebrovascular lesions (1990):
While she acknowledged being in a hospital, she said she was admitted in order to lose weight. She denied any motor deficit on her left side, but said she had problems moving her right side (“I have had a cast covering the whole right side of my body for the past 30 days”). When her left arm was shown to her she recognized it and acknowledged she had problems moving it, but said her main motor problem was her right arm. Several minutes later, however, she denied having any motor problem on the left side, and said she had spent most of the day climbing stairs and walking around the hospital with the patient next to her (who was actually quadriplegic). On repeated occasions, the patient tried to walk by herself (as if she had no motor problems). She said she had the feeling that the left arm did not belong to her but to a nearby person. She disliked the left arm, and hit it several times because “it does not obey me.” She called it “zodoquio” (a neologism).
From Feeling touches in someone else’s hand (2001). A patient after a stroke started having somatoparaphrenia in the left hand. She would recognize her left hard as her niece's hand, and could not feel touch in it. However,
When F.B. was required to report touches delivered to her niece’s hand, her tactile imperception dramatically recovered (Table 1). Immediately after the experiment, we asked F.B. how she could report touches on someone else’s hand. Her response was initially elusive; however she eventually explained the phenomenon as follows (though adding ‘Yes, I know, it is strange’): her absent-minded niece would always forget her hand on the patient’s bed while leaving the hospital, so that F.B. used to take care of it until the niece came back to visit her again.
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