Books >> The Brain Has a Mind of Its Own
MY BRAIN AND I ARE ONE
I once attended the wedding of a thirty-five-year-old patient who five years earlier had come to me after seeing in broad daylight the ghost of her dead first husband. At our first meeting she told me about the ghostly visitor, but only after I had asked a simple question: "Has anything strange ... you know ... out of the ordinary ever happened to you?" "Like what?" she responded, fixing upon me a pair of now fully dilated eyes. She then revealed that on occasion she experienced a wave of fear accompanied by "strange sensations," such as a metallic taste in her mouth or a smell in the environment like that of burning rubber. On other occasions while in her home she felt as if everything had been "somehow altered." Sometimes the alteration involved her own sense of herself as somehow split into two people: an observer who commented on her actions, and an actor who carried them out. ("Yet both of them are me," she said.) When I asked for further details, she said: "It's as if I'm a character in a science fiction novel who inhabits one dimension of reality while the rest of the world lives in another." The electroencephalogram, which measures the brain's electrical activity, provided me with proof of what I already suspected. Karen's disturbed sense of herself originated from an epileptic discharge deep within the left temporal lobe of her brain. The temporal lobe is responsible for our sense of connectedness, our personal identity, the feeling of belonging we get from familiar surroundings. When it functions normally, we have no apprehensions about who we are, our situation, or the nature of things. But when the temporal lobe is diseased, strange things can occur. A seizure originating in the temporal lobe can produce disorientation, feelings of having previously experienced events happening at the moment (déjà vu), or equally troubling feelings that familiar objects and people are new and vaguely threatening (jamais vu). Another temporal lobe epileptic I once treated spent long hours in the middle of the night writing philosophy. He filled notebook after notebook with philosophical ramblings that in broad daylight he was able to recognize as not likely to be of much interest to anybody but himself. A serious man, he made me think of prophets and seers. At times his ruminations on the nature of the spiritual world became ecstatic, almost sexual. Dostoevsky, a temporal lobe epileptic, described the process in The Idiot:
There was always one instant just before the epileptic fit ... when suddenly in the midst of sadness, spiritual darkness and oppression, his brain seemed momentarily to catch fire, and in an extraordinary rush, all his vital forces were at their highest tension. The sense of life, the consciousness of self, were multiplied almost ten times at these moments which lasted no longer than a flash of lightning. His mind and his heart were flooded with extraordinary light; all his uneasiness, all his doubts, all his anxieties were relieved at once; they were all resolved into a lofty calm, full of serene, harmoniously and hope, full of reason and ultimate meaning. But these moments, these flashes, were only a premonition of that final second (it was never more than a second) with which the fit began. That second was, of course, unendurable. Thinking of that moment later, when he was well again, he often said to himself that all these gleans and flashes of supreme sensation and consciousness of self, and, therefore, also of the highest form of being, were nothing but disease, the violation of the normal state; and if so, it was not at all the highest form of being, but on the contrary must be reckoned the lowest. Yet he came at last to an extremely paradoxical conclusion. "What if it is disease?" he decided at last. "What does it matter that it is an abnormal intensity, if the result, if the instant of sensation, remembered and analyzed afterwards in health, turns out to be the acme of harmony and beauty, and gives a feeling, unknown and undivined till then, of completeness, of proportion, of reconciliation, and of startled prayerful merging with the highest synthesis of life?"
An encounter with a person suffering from temporal lobe epilepsy raises a question philosophers have argued about for centuries: What is the relationship of mind to brain? How can a disturbance within a fairly circumscribed area of the brain produce such transcendental experiences? Most experts have taken refuge from such questions in a vague and untidy dualism that, until fairly recently, was supported by our experiences with physics and machines. Dualism, the metaphysical conception that body is separated from mind, originated with the seventeenth-century philosopher René Descartes. Descartes proposed that the body, especially the brain, is a machine with functions that can be explained by the mathematical laws of physics. But over the past sixty years physics has changed greatly. According to the principles of quantum physics the observer cannot be meaningfully separated from the experiment that he or she is conducting. Indeed, the viewpoint of the observer often determines what is recorded by the experiment. The most famous example of the observer effect occurs in the double-slit experiment, wherein a stream of particles is directed toward a screen. A second screen, containing two long parallel slits, is then placed between the stream source and the original screen. With the two slits open the particles arrange themselves in bands alternating with blank spaces in between. But when only one slit is open, the particles fill in the blank spaces. "Particles or waves? Which is the true picture?" asks physicist Fred Alan Wolf. "It depends on which part of the experiment is being performed. With one slit open, the stream is composed of particles. With two slits, it is composed of waves." The nature of what is being measured depends on how the observer sets up the experiment. The observer effect holds true for brain/mind dualism, as well. When I listen to my patients tell me about a frightening vision or hallucination-something far removed from everyday experience, I'm encountering the world of mind. But if I record my patient's brain waves during a hallucination and detect an epileptic seizure within the temporal lobe, I've shifted my focus, like the scientist in the double-slit experiment, from one aspect of reality to another. Marcus Rachel, head of the brain study group at the Washington University School of Medicine in St. Louis, suggests another way Of thinking about such a paradox: "Because the brain is a physical structure, it exists in space; but the mind operates in time alone. " The brain as I stare at it depicted on a CAT scan or set out upon an autopsy table is very much an object. It takes up space; I can see it or its representation; I can pick up the autopsy specimen. We're talking about spatial matters here. Mind, in contrast, can be captured only in the temporal dimension. My thoughts require time before I can communicate them to you in the form of words. Without motion or some form of behavior, mind cannot be inferred. Indeed, if I don't move or speak, can you really be sure I'm thinking at all? The closer we look, the more difficult it is to maintain any neat division between mind and brain. Suppose I shout the word fire in a crowded theater. That word, fire, is conveyed by means of sound waves that stimulate the tympanic membranes in the ears of the listeners. Within milliseconds electrochemical events occur in the auditory nerve. They then traverse the labyrinthine pathway within the brain from auditory cortex to auditory association area to limbic system. There the word fire is loaded with fears traceable to the first caveman who burned his fingers before a campfire. Sound waves stimulate tympanic membranes, and physical alterations take place in the brain. Milliseconds later, thanks to the limbic involvement, the hypothalamus and sympathetic nervous system are drawn into the fray: heart rate increases, blood pressure rises, breathing be- comes constricted and labored. The result: hundreds of people jump up from their seats to rush toward the exit--all in response to a concept conveyed by a mere word. Shouting the word fire exerted a powerful influence on matter. At a minimum the physical structure of the brain has been changed, albeit momentarily. Other words and phrases of a different sort (You're a failure; I want a divorce; I love you) exert more permanent modifications within the brain. The PET scan of a schizophrenic or a manic-depressive shows a distinct variation from what, for lack of a better term, we call a normal brain. On the whole it's likely that these distinctions represent differences in the organization and function of the brains of those unfortunates who suffer from these illnesses. Alter the brain and you alter thoughts, feelings, and personal identity. And if you change an attitude or modify your own or someone else's behavior, you've worked a miracle, performed a successful experiment in psychokinesis: you've used the intangible mind to transform something in the physical world. Mind can affect brain; brain can affect mind. But can either be separated from the other? Not any more than the other side of this paper can be separated from the side that you are now reading. My experience with temporal lobe epileptics has raised a haunting personal question: How many of my own habits and propensities are determined for me by my brain? To what extent am I anything other than my brain? Is there any way of separating the brain from the person who just asked that question? My way of coping has been to fashion a simple mantra I repeat silently from time to time: "My brain and I are one. My brain and I are one." But even as I think and speak these words--my brain changing all the while as I do so--I still find it difficult to believe that this three- pound mass of protoplasm with the consistency of an overripe avocado is the seat of who I am, of who we all are.
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