Dissecting the Self
Early in my career as a medical student I was required to perform a dissection of the brain using an old atlas as a step-by-step guide. The brain was bathed in a jar of preservative and wrapped in white cheesecloth. I took it out carefully and placed it on an orange cafeteria tray. The first procedure called for the removal of the gray matter in order to see the underlying brain structures. Beginning in a section that the atlas identified as the temporal lobe, I slowly and gently scraped away its cortical surface using a beveled wooden probe. Having barely exposed a centimeter of brain matter, I was struck by the realization of what I was actually doing. Had this person's memory of his childhood just been scraped away? Perhaps his recall of his whole family now was gone, or simply his recollection of a family outing on a warm summer day in July. Lying inert on this cafeteria tray was the substrate of this person's mind. I picked up the brain again, held it in my hands, and looked at it anew. This was a person's essence, humanity, and entire life experience now frozen in space and time. Who might he or she have been? It became apparent that studying the physical brain would allow me to explore some fascinating questions such as: What is the self? Where is it located in the brain? How does the brain produce a unified self? What is the relationship between the brain and the mind? The answers to these questions reflect the knowledge I have gained over the years as a neurologist and psychiatrist from patients with disorders of the self, and are the subject of this book.
The Patients
The first part of the book looks at patients with brain damage who have altered egos, a change in the brain that transforms the boundaries of the self, the relationship between the self and the world, the self and other people, and the self to itself.1 I use the term “ego” not in a Freudian sense, but rather to refer to the “inner I” that we feel to be the most intimate aspect of the self. As philosopher Colin McGinn points out, there are many words that refer to the “I” including “self,” “subject,” “person,”
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or “ego.”2 It is to these aspects of the self that I refer when speaking of the “ego.”
Patients with altered egos as a result of brain damage experience a transformation in the personal, the aspects of identity that are most significant to the self. These persons might reject one of their arms, disown a spouse, or claim nonexistent relationships to strangers. They might have imaginary brothers, children, or alter egos. There is much to be learned from these cases. As slicing an apple reveals its core, the neurological lesion, or damage, in these patients opens a door into the inner self; it provides an opportunity to examine the physical structure of the self and to see how the self changes and adapts in response to the damaged brain.
Most of the patients described in this book are everyday persons—people with whom any one of us could identify—who undergo transformations of their senses of identity and worldview. Before their brain disorders disrupted their normal functioning, many led rather ordinary lives. They were adults of various ages, accountants, electricians, secretaries, homemakers, business executives, accomplished musicians, or unemployed adults whose brain disorders prevented them from functioning in their previous capacities at their jobs, within their families, or in personal relationships. In some cases, a spouse, family member, or a concerned neighbor brought them to my care. Consider the following case, one of the first patients referred to me for a remarkable neurobehavioral problem.
John
The attending physician in the ER referred a middle-aged electrician, John, and his wife, Joyce G., to my office for a consultation. The patient entered alone and told me that his wife had stopped to make a phone call and would be joining us momentarily. He was a tall, husky, neatly groomed man wearing blue jeans, which oddly enough were wet on the right hip pocket. Before he took a seat, I asked him if he had sat in something wet or perhaps spilled coffee on himself. He said no. John then offered his right hand to shake mine and I was astonished to see that he had what looked like severe chemical burns on his hands; the skin was actually seared away, exposing the muscle and bone.
I asked John if he was aware of the condition of his hands. He casually responded that he had been doing some work on the plumbing in his house and had gotten a few “little burns.” It was clear that John was aware of them but entirely indifferent to their severity. He had applied no
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bandages and had just offered to shake my hand despite the wounds. He simply did not seem to care about the injury. The most extraordinary thing about John was how normal he appeared in other respects. He spoke clearly and intelligently, and I discerned no hint of dementia or psychosis. There was a striking contrast between his superficial mental integrity and his indifference to his medical condition.
Just then his wife entered the office. “Well, Dr. Feinberg, did you get him to talk?” I inquired how her husband got burned. She reported that she had recently observed John unclogging the kitchen sink, after which she, too, had noticed that his jeans were wet at the hip. She had assumed that he merely had splashed himself with water, but later on she noticed blood and pus in his clothing while sorting it for the laundry. When she asked John about the stains, he seemed unconcerned. It was then that she noticed the horrible condition of his hands. She determined that chemicals in the drain cleaner had apparently eaten his flesh down to the muscle and he hadn't even known it. The wound had festered for days, yet John carried on his daily routine apparently without noticing the injury.
She began to cry. “Doctor, you don't realize what's going on? He seems perfectly fine to you in here. But when we go home, he will immediately head downstairs into the basement, turn out all the lights, and sit in the dark. He won't budge. I have to bring him breakfast, lunch, dinner—he won't eat if I don't bring him food.”
What was the problem with John? His wife explained that John was currently out of work, and maybe this had made him a bit down. However, his mood seemed bright, and he said he did not feel depressed. Furthermore, depressed patients often lose their appetite and John had not lost any weight. He was sleeping well at night. “No, his symptoms didn't look like those of depression,” I thought to myself.
I then asked why John was out of work. It turned out that he had had an accident a couple of months back. He had fallen from a scaffold, hit his head, and been hospitalized for several weeks. His wife recalled, “Come to think of it, his doctors did mention something about his brain, but I didn't quite understand the problem.”
That was interesting. John's formal mental status exam—which includes tests of orientation, language, memory, and other cognitive functions—confirmed that John was cognitively intact. Indeed, it eventually turned out that every aspect of John's neurological exam was normal. On the areas of his hands that were free of burns, he was able to distinguish sharp from dull stimuli, and hot from cold stimuli. This finding meant that John's indifference to his burns could not be due to simple numbness in
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his hands, which would suggest a problem with the pain nerves in his hands or with the spinal cord carrying pain information to his brain.
I needed to learn more about the condition of John's brain, so I ordered an MRI (Figure 1-1.)3One can see from this scan that large portions of John's right frontal and parietal lobes and a part of his left frontal lobe have been destroyed by a neurotraumatic accident. This finding accounted for John's problem. Because of the extensive damage to his brain, John suffers from a rare condition known as pain asymbolia. He can distinguish among different types of stimuli, but painful stimuli no longer carry any emotional impact, which causes his indifference to his wounds.4 Once the disorder was recognized, we were able to help John avoid the sort of dangerous situations that might lead to physical harm.
The Perplexing “Inner I”
John is one example of the many ways in which a change in the brain can transform the self. But from the standpoint of neurobiology, it is not clear what the self really is or how the brain creates it. The later chapters of this book will address these questions. The nature, significance, and
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Figure 1–1. On the left is a side view of a normal brain. The locations of the frontal, parietal, temporal, and occipital lobes are indicated. The line that runs through the brain indicates the level of the MRI slice of John's brain that appears on the right. In the scans shown in this book, cross-hatched regions represent areas of brain damage. John's scan showed regions of encephalomacia (softened, damaged, lifeless cortical tissue) that occurred as a result of John's head injury. The area of damage included large portions of the right frontal and parietal lobes. In the left hemisphere, the damage was confined to the anterior and medial portions of the frontal lobe. |
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even the existence of the self has been a subject of debate for centuries.5 Philosopher Immanuel Kant (1724–1804) was a proponent of the fundamental existence and primacy of the self. He stated that even before there is thought, before we can know anything about the world or ourselves, there must be a unified “I” as the subject of experience. Kant placed the primordial, unified “I” at the center of his philosophy and argued that the inner “I” creates coherence and lends order to our experience and perception.
The psychologist and philosopher William James (1842–1910), on the other hand, was not a fan of Kant or of the notion of a primordial unified self. He devoted several pages of his monumental work The Principles of Psychology to criticism of Kant's theory. According to James, the “ego” was nothing but “a ‘cheap and nasty’ edition of the soul.”6 James held that there is something that could be appropriately referred to as the self, but he denied that there is any primordial “I” behind this self.
James maintained that there are only “passing states of consciousness,” and our experience of mental unity is simply due to the fact that we as individuals experience successive mental states in our stream of consciousness that are uniquely our own. Put all these experiences together in a single mind and you get a self—without any inner “I” pulling it all together. James even made the extreme claim that if somehow one could put together several independent minds that shared the same experience and past, one could produce the same mental unity among minds that we as single minds experience:
Successive thinkers, numerically distinct, but all aware of the same past in the same way, form an adequate vehicle for all the experience of personal unity and sameness which we actually have. And just such a train of successive thinkers is the stream of mental states. . . which psychology treated as a natural science has to assume.
The logical conclusion seems then to be that the states of consciousness are all that psychology needs to do her work with. Metaphysics or theology may prove the Soul to exist; but for psychology the hypothesis of such a substantial principle of unity is superfluous.7
Unlike James, many neuroscientists since have weighed in to support the unified self, and some of their ideas will be reconsidered in this book. The neurophysiologist Charles Sherrington, for example, was a firm believer in the unified self. Sherrington beautifully summarized in his book Man on His Nature why he felt compelled to posit the existence of the self:
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This self is a unity. The continuity of its presence in time, sometimes hardly broken by sleep, its inalienable “interiority” in (sensual) space, its consistency of view-point, the privacy of its experience, combine to give it status as a unique existence. . .. It regards itself as one, others treat it as one. It is addressed as one, by a name to which it answers. The Law and the State schedule it as one. It and they identify it with a body which is considered by it and them to belong to it integrally. In short, unchallenged and unargued conviction assumes it to be one. The logic of grammar endorses this by a pronoun in the singular. All its diversity is merged into oneness.8
If Kant and Sherrington are correct, as I think they are, and there is such a thing as a self, we need to explain how the brain, which is composed of billions of individual neurons, creates the single and unified entity we call the self. The clinical cases will demonstrate that there are many brain regions that play a role in creating and maintaining a self. But modern neuroscience has now convincingly shown that there is no central place where everything in the brain “physically comes together”; no place where the infinite diversity of the brain can physically combine to create a centralized mind or unified self. Science writer John Horgan, in his recent and provocative book The Undiscovered Mind, called this problem the “Humpty Dumpty dilemma”:
This conundrum is sometimes called the binding problem. I would like to propose another term: the Humpty Dumpty dilemma. It plagues not only neuroscience but also evolutionary psychology, cognitive science, artificial intelligence—and indeed all fields that divide the mind into a collection of relatively discrete “modules,” “intelligences,” “instincts,” or “computational devices.”Like a precocious eight-year-old tinkering with a radio, mind-scientists excel at taking the brain apart, but they have no idea how to put it back together again.9
The problem of mental unity poses a real challenge for any neurobiological theory of the self. If all brain regions that contribute to the self can be enumerated and tallied as if they were computer modules, how are they integrated so that we exist as unified, single selves? What is it about the brain that creates the subjective sense that we possess a single and unified point of view, an inner “I”? What keeps the neurons of our brains from going off in their own directions?
The difficulty with previous solutions to the Humpty Dumpty dilemma is that they tend to view the brain and mind as hierarchically organized like a pyramid. All the brain areas that contribute to the self end up at the top
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Figure 1–2. Many models of the mind envisage the brain as a hierarchy in the shape of a pyramid. The many parts of the brain that contribute to the self and mind make up the base of the pyramid. These parts are combined and organized to create higher levels of the hierarchy. Suddenly, and somewhat mysteriously, a unified self is supposed to “emerge” at the top. |
of this hierarchical system and the unified self and mind, the inner “I,” mysteriously emerge, like the eye atop the pyramid in a dollar bill (Figure 1-2).
The problem with this account is that the brain is not organized like a pyramid, but rather operates like the living organism of which it is a part. All living things are hierarchically organized, but the hierarchy does not have a “top” or “bottom” like a pyramid. Living things representnested hierarchies. In the nested hierarchy of a living thing, all parts make a contribution to the life and activity of the organism. In the nested hierarchy of the self, many parts of the living brain make a contribution to the self. I will try to show that the neurobiological self can be understood as a nested hierarchy of meaning and purpose.
One of the most interesting features of this view of the self is the ultimately personal nature of the nested self. Individual meaning and purpose only exist for the individual and are a part of our being. In our current age of miraculous computer technology, we have lost sight of the simple fact that the mind is a living thing that is an integral part of our existence as living beings. In the concluding chapters, I argue that when the notion of personal being is included in our theories about the brain, we can begin to comprehend the elusive neurobiological basis of the self.