If one places phantom limbs within the context of the self, the phenomenology of phantom limbs, confronts us with some very interesting ontological questions regarding mental causation and the function of illusion. Phantom limbs do not exist in the physical world as they are unconsciously generated constructions of the mind/brain As phantom limbs are not in the physical world, we say that they are illusory. The self is also a construction of the mind/brain : the self does not extend into the physical world, and can also be described as an illusion. But we should not depreciate or disparage belief in illusions as false conceptions; if the self is an illusion, it is an illusion without which we cannot live. Might the construction of phantom limbs also signify a survival function? These are disturbing illusions that nevertheless may represent an attempt at restoration of the sense of unity, cohesion and continuity of the self. These are some of the questions that I plan to explore.
The neurologist V.S. Ramachandran(Ramachandran 1998)reports that seventy percent of those who suffer from phantom limbs experience pain, and the pain may persist for as long as 25 years after the injury. In most cases the pain cannot be attributed to any identifiable material source such as stimulation of frayed nerve endings, called neuromas. This fact confronts us with the question: where does one look in one’s search for a causal explanation? If the pain is not a sensation produced within the body in current time, the mind/brain may have reactivated the memory of sensations from the limb before it became a phantom. If the painful phantom limb represents a remembered pain, does it serve a biologic purpose, or is the pain meaningless? If the pain cannot be attributed to neuromas ,the pain of phantom limbs must be attributed solely to some process within the mind/brain without a sensory source. It is a creation of the brain in the absence of sensory inputs. The sensation of phantom limb pain can be thought of as an hallucination contained within the more global illusion of the self. The pain of phantom limbs would seem to be analogous to the hallucinations we experience while dreaming. We are essentially cut off from the world when we dream. While bodily sensations may on occasion be incorporated into a dream, the visual images of dreams are entirely created from within.
Some phantom limbs can be experienced as if they are performing customary motor acts of every day life such as waving goodbye or reaching for a cup. Ramachandran observed a patient whose forearm was amputated and his hand was telescoped into the stump. If he attempted to shake hands or reach out to grab a cup he experienced the illusion that his phantom would extend to normal length. On one occasion Ramachandran pulled the cup away and the patient yelled in pain claiming that he had wrenched the cup away from his fingers causing his phantom to telescope unexpectedly. This patient retained an illusionof agency.
Ramachandran (Ramachandran 1998) also described how the illusion of agency can be induced in a patient whose phantom was felt to be paralyzed and lost his sense of agency. This phantom limb patient experienced the illusion of agency by means of Ramachandran’s now famous “virtual reality box”. “The box is made by placing a vertical mirror inside a cardboard box, with the roof removed. The front of the box has two holes through which the patient inserts his good arm and his phantom arm “The mirror superimposes an image of his good arm over the phantom. The patient was asked to make symmetrical movements in both arms and the patient reported that the phantom felt as if it’s motion was restored. Ramamachandran reports that the patient whose phantom was frozen and paralyzed now experienced movement in the phantom. The illusion of agency was induced and re-established by the superimposition of the sight of actual movement in his intact hand. These experiments that demonstrate that the sense of agency can be manipulated, suggest that our feeling of agency, is just that, a feeling or a sensation and nothing more. We can experience a sense of agency when there is no actual cause and effect .This experiment supports the premise that our conscious will is also an illusion. We need to believe in the causal effectiveness of our consciousness will.
Our earliest experience of self in infancy may be induced by motor actions that create an accompanying sense of agency. If belief in the agency of conscious will is an illusion, it is an illusion that is totally compelling . I will suggest that we need to believe in the sense of agency as a sense of agency is our primordial sense of being in the world. As such, it is a core element of our sense of self. The need to maintain this feeling of efficacy is an imperative and transcendent value.
Many observers including William James and Sigmund Freud have recognized that our bodies are the earliest and most primitive source of self experience. (Modell 1993) The unconscious body image or schemata, and its associated conscious feeling states, is the infant’s first experience that I am who I am. The body image is a construction of the mind/brain that is continually recontextualized and updated by experience. The qualities of the self are paradoxical in that a sense of constancy is maintained while at the same time our experience of self is continuously altered, and needs to be continuously altered. If we accept this paradox, there is no inconsistency in playing with multiple identities yet at the same time retaining a belief in the sameness and continuity of the self.
It appears likely that the experience of sameness over time may be related to the constancy of the body image. There is also a suggestion that the body image itself may exist as a genetic given , an inherited template, or schemata, that is present prior to experience. One of our panel members Peter Brugger (Brugger, Kollias et al. 2000)and his colleagues observed four phantom limbs in an individual born without limbs. In this individual, the construction of the phantom limb could have had no relation to the memory of sensations from the extremities.
We normally update and refresh our body image through multiple different sensory modalities or portals, such touch, mediated through the skin, vision and proprioception. Proprioception is an unconscious awareness of our body in space , derived from sensations arising from muscles, joints and tendons. The body image , the primordial self when updated through these many sensory portals creates a sense of ownership and agency. Ownership refers to a state of being in which the body is recognized as belonging to me. Ownership implies not only that it is my body , but that my body can be differentiated from other bodies. Here the sense of touch functions as a boundary, and the self becomes a containing envelope. This sense of ownership of one’s body can be observed in infancy. For example(Stern 1985), Siamese twins, who sucked each other’s fingers, were able to differentiate their own hands from those of the other. Some experimenters (Botvinick 2004)have demonstrated that by means of visual and tactile inputs an illusory sense of ownership can be transferred to a rubber hand. This can occur if the subject’s own hand is hidden and the rubber hand is in view and both hands are simultaneously stroked. Agency, is somewhat different from the sense of ownership , as agency includes a belief that one is the author and originator of one’s actions, and furthermore that an action is the consequence of the conscious will. Agency unlike ownership includes the idea of causality. Both the sense of agency and the sense of ownership may prove to be illusions.(Wegner 2002)
Let us imagine how an infant might develop a sense of agency. At first the infant’s limbs flail in a reflexive, involuntary, and unconscious fashion. At some point in time the infant has the experience of controlling the movement of their limbs and hence develops a sense of agency and mastery. The infant feels that the limb has responded to their command. An involuntary action has been brought within the control of the self.
This sense of agency and ownership of the body is an essential element in maintaining a sense of the intactness and coherence of the self. I can illustrate this by means of two anecdotes where the loss of this sense of agency and ownership had a devastating and profound effect upon the organization and experience of the self. This first anecdote was provided by the neurologist Oliver Sacks in his autobiographical account “ A Leg to Stand On” (Sacks 1984) Sacks tells us that he encountered a bull when climbing a mountain in Norway. Fearing attack he ran down the mountain and suffered an injury that seriously damaged the muscle and nerves of his leg. He lost all sense of proprioception in that leg, he lost an unconscious affirmation that the leg existed as an object in the world. It was in a sense the obverse of a phantom limb: his leg was there, it was not missing , he could infer that it was there, but he could not move it or feel it. It was an absence, not a phantom presence, but its effect upon the body image and the self was similar to a phantom limb. He described this loss of proprioception as follows: “one may be said to own or possess one’s body — at least as limbs and movable parts — by virtue of a constant flowing of incoming information, arising ceaselessly, throughout life , from the muscles, joints and tendons. One has oneself, one is oneself, because the body knows itself, confirms itself, at all times, by this sixth sense.” The more I gaze at the cylinder of chalk (the cast), the more alien and incomprehensible it appeared to me. I could no longer feel it as mine, as part of me. It seemed to bear no relation what ever to me. It was absolutely not me — and yet, impossibly, it was attached to me — and even more impossibly, continuous with me.” Sacks further states after the cast was removed : “the flesh underneath my fingers no longer seems like flesh. It no longer seemed like material or matter. It no longer resembled anything. The more I gazed at it and handled it, the less it was there, the more it became Nothing and nowhere. Unalive, unreal it was no part of me — no part of my body, or anything else. It didn’t “go” anywhere at had no place in the world. I lost the inner image , or representation, of the leg. It was a disturbance, an obliteration of its representation in the brain — of this part of the body image.” Sacks goes on to describe his gradual recovery and regaining a sense of agency. Initially he felt that his leg did not belong to him when it refused to obey orders. In Sack’s account: ”when I awoke I had an odd impulse to flex my leg – and in that self-same moment immediately did so! Here was a movement previously impossible. I had thought it and done it. The idea, the impulse, the action were all one. The power of moving, the idea of moving, the impulse to move would suddenly come to me — and then suddenly go. What was central in this process of gaining control of movement was the awareness of the self. In his words “these flashes of involuntary spontaneous unbidden movements involve me: they weren’t just muscle jumping but me remembering” they involve me and my mind no less than my body”
The second anecdote is another autobiographical account, this time from John Hull (Hull 1990) who became blind in mid-life and lost a sense of ownership of his body. With the loss of vision he was unable to update his memories of himself. He was painfully aware of the absence of his body image :” The fact that one can’t glance down and see the reassuring continuity in the outline of one’s own body, moving a distant foot which so to speak waves back saying yes I hear you I am there. There is no extension into space , so that I am nothing but a pure consciousness , I am dissolving I am no longer concentrated in a particular location , which would be symbolized by the integrity of the body“ He then refers to the inability to recontextualized the body image:
“I know what I look like because of memory of photographs and memories of seeing myself in the mirror. So I know that my memories of myself are out of date and the strange thing is that I have no way of updating them. This means that I have a sense of cognitive dissonance what I think about myself.” In both cases, Oliver Sacks who lost his sense of proprioception and John Hull who lost his vision, there was an inability to experience a unified and coherent body image added to which there was an inability to update their body image through sensory inputs. As a consequence both men suffered from a significant and severe depression. Body image and the self are intimately linked together.
When an extremity is lost, there also a loss of a sense of agency and ownership of the body, due to the absence of sensory inputs. All of this contributes to a massive and profound disorganization of the self. Might it be true then that the phenomenology of phantom limbs can be understood as a miscarried attempt to restore the integrity of the body image by providing hallucinatory sensory inputs? I share the view that the hallucinated pain and the illusory sense of agency although disturbing, may represent an attempt to compensate for the absent sensory inputs and re-establish some semblance of a unified body image. This compensatory process is self generated and entirely unconscious. There is a clear analogy here to the self-generated hallucinations of dream, that are also created in the absence of sensory inputs. But the self-generated sensory inputs of the phantom limb, unlike the dream, tend to be unvaried.
I’ve tried to illustrate how the sense of self, as a cohesive entity, depends upon the sensations derived the body and that the body image in turn needs to be continuously recontextualized through a variety of sensory modalities. It is equally true that the self needs to be continually recontextualized not only through sensations but through emotional experience. If one is cut off from all feelings one will think of oneself as empty or dead. If taken further one may begin to doubt the reality of the self and fear that the self is disintegrating.This fear of annihilation of the self is perhaps the most severe type of anxiety that anyone can imagine.
I must say again that our sense of self is fundamentally paradoxical. (Modell1993) We feel that we are of a sameness, we experience an unchanging core identity that persists over time, yet the self requires that it be constantly altered in response to lived experience. The self is nearly co-terminus with consciousness, which as you know, William James thought of as a flowing stream. This paradox of the self disturbed William James, he wrestled with it throughout his life and never found a solution. James was unable to reconcile how a momentary state of consciousness could connect with the stored memories of previous selves and create the unity that we experience as the sameness of our identity. This paradox still remains a mystery – but an explanation may be found in neurobiology. The continuity of the self may be an unconsciously generated illusion analogous to the phantom limb. But unlike the phantom limb, the self is constantly enriched through the recontextualization of memory. The neural correlates of this process may correspond to what Gerald Edelman described as re-entry.
The phantom limb may perpetuate painful sensation in order to support the illusion of the continuity of the self. Instead of painful bodily sensations psychoanalysts commonly observe the persistence of painful belief systems that contribute nothing to the well being of the individual, but also support the illusion of the continuity of the self. It is if the person is saying:” these may be self-destructive thoughts but I lived with them all my life and without them I would not know who I am” These fantasies may form a belief system in which the self is viewed as fundamentally defective, or that one’s love is poisonous, there can be nearly infinite variations on this theme. Such fantasies may be unconscious or partly conscious. However, if unconscious, enabling such malignant unconscious fantasies to become conscious and analyzing the origins of such beliefs may change nothing. It would appear that the persistence of such inimical beliefs may be due to the fact that they have been created in early childhood and have therefore become woven into the very fabric of the self. To relinquish such ideas would alter the illusion of the continuity of the self. Again, this need to maintain the illusion of the continuity of the self is a transcendent value that trumps reason and one’s sense of what is real.
In closing I would like to look at the concept of illusion itself. We no longer believe that the representations of the facts and objects in the world that are created by our minds and brain in any sense mirrors that external reality. For example, colors do not exist in the physical world, they exist only in our minds. Colors could be thought of as an illusion. What exists in the physical world are not colors but only wavelengths and packets of light. The neurophysiologist Semir Zecki (Zeki 1999) has shown, interestingly enough, that the brain constructs an illusion of the sameness and constancy of color. Because we view objects under different conditions of illumination, the wavelength composition of light reflected from these objects constantly changes. The illusion of constancy is achieved in the brain by a neural process that compares the reflected wavelengths of light. Some neuroscientists also believe that the visual experience of moving objects is also an illusion as the brain records discrete visual images like snap shots that are neurally transformed into the visual illusion of motion. Brains create the illusion of motion just like the movies.
Our experience of color is an illusion but it is a very different sort of illusion when compared to the illusion of the self. For color has as its source from something invariant in the physical world. Of course, this cannot be said of the self. The self is a very different sort of an illusion , one in which there is no fixed correspondence between what the mind /brain constructs and what exists in the physical world. The fact that the self is an illusion, that there are no selves in the physical world, does not mean that the self does not exist. It would be a grave mistake to believe that the self does not exist as a psychic reality, as some philosophers have concluded. That the self does not exist has been asserted by philosophers since David Hume, who, in the 18th century, viewed the self as a transient theatre of the mind.. The self is an illusion but it is an illusion, without which we cannot live. The investigation of phantom limbs has surprisingly reaffirmed the psychoanalytic belief in the transcendence of psychic reality and the centrality of illusion in human life. It needs to be added that the neuro-psychological process that creates these illusions is entirely unconscious.
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