| ZEN PHYSICS (what is this?) The Science of Death, the Logic of Reincarnation David Darling 
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You have to begin to lose your memory, if only in bits and pieces, to realize that memory is what makes our lives.
– Luis Buñuel
Almost everything you do and think is based on what your brain remembers has happened to it in the past. And everything you do and think in the future will serve to reinforce the patterns of behavior and response associated with the particular person that you, and others, think of yourself as being. All new experiences and perceptions from one moment to the next are interpreted in the context of your apparently central, abiding self. Memory is your link with the past and your basis for action in the future.
To be a person, one must have a memory – a unique, accessible set of recollections – because to be a person means to hold one’s life story and be actively, intimately involved with it. We must be able to see who we are now in terms of who we have been at different, successive stages along our journey from early childhood. We must hold the script to the inner drama that is ourselves, to know our own narrative. For if we cannot do this, we are without an identity or self.
Fortunately, our memories are remarkably durable. They survive despite the never-ending metabolic turnover of particles in every cell of our bodies, a fact lyrically captured by Loren Eisley in The Immense Journey:
I suppose that in the forty-five years of my existence, every atom, every molecule, that composes me has changed position or danced away and beyond to become part of other things. New molecules have come from the grass and the bodies of animals to be part of me a little while, yet in this spinning, light and airy as a midge swarm in a shaft of sunlight, my memories hold, and a loved face of twenty years is before me still.Atom for atom and cell for cell substitution poses no threat whatever to the self, as experience clearly shows. In the case of people who recover fully after having been in a coma for several months there has been an almost complete replacement of their constituent atoms in the period during which they were unconscious. Yet, upon waking, they have no sensation of being any different or of any time having passed.
A far more extreme case of the “persistence of self” was imagined by H. G. Wells in The Sleeper Awakes, in which a young man falls into a trance that lasts two centuries. As the trance begins, Wells asks: “Where was the man? Where is any man when insensibility takes hold of him?” And two hundred years later:
What a wonderfully complex thing! this simple seeming unity – the self! Who can trace its reintegration as morning after morning we awaken, the flux and confluence of its countless factors interweaving, rebuilding ... the growth and synthesis of the unconscious to the sub-conscious, the sub-conscious to the dawning consciousness, until at last we recognize ourselves again. And as it happens to most of us after the night’s sleep, so it was with Graham at the end of his vast slumber.When he conceived this fantasy Wells could hardly have imagined how close reality was to emulating his fiction. Between 1916 and 1927, there occurred a worldwide epidemic of encephalitis lethargica, or sleeping sickness. Nearly five million people contracted this devastating illness, one third of whom died shortly after as a result. But for others there followed a bizarre trancelike state – not unconsciousness but a conscious stasis – in which time seemed to stand still. It was for them as if the world, instead of giving the appearance of continuous change as in a movie, had instead become stuck in a single frame.
Then, as in Wells’s story, came the awakening. More than forty years after they had been struck down, the victims were temporarily and almost miraculously freed from their frozen state by the administration of massive doses of the anti-Parkinson’s drug L-dopamine. For those who had been more deeply affected, their last living memories were of the world as it had been shortly after World War I. More than four decades had elapsed during which all the substance of their bodies and brains had been replaced many times over. But upon resuming relatively normal consciousness, the patients were in no doubt as to who they were. It was for them as if there had been no vast temporal chasm. And for this very reason, they were confused, disoriented, by what they found, or did not find, in the new world into which they had been catapulted. One profoundly affected patient, for instance, upon being revived used strangely outmoded turns of phrase and spoke of Gershwin and other contemporaries as if they were still alive. She knew it was 1969, because during her trance she had absorbed news of current events such as the bombing of Pearl Harbor and the assassination of Kennedy, but she felt with overwhelming conviction that it was 1926.
In his remarkable account of such cases in his book Awakenings, the neurologist Oliver Sacks supports the argument, first expressed by Leibniz (“Quis non agit non exitit”), that we must be active or we cease, in any ontological sense, to exist – that activity and actuality are one and the same. How else, he wondered, could the instantaneous return to normal movement and speech be explained in a person who had been totally inactive for more than forty years. Most of us stiffen up if we remain in the same position for a couple of hours. Six weeks with a broken leg in a cast and we need at least a few days to recoup the strength in our muscles and the flexibility in our joints. Yet some of the sleeping-sickness victims, having been virtually motionless for half a lifetime, were, within a few seconds of their “unfreezing,” jumping up, walking about with great energy, and chattering excitedly to anyone who would listen. The only satisfactory conclusion Sacks could draw was that during their trance there had been no subjective duration for the victims whatever. It was as if the “current of being” (Sacks’s phrase) had been abruptly turned off and, more than forty years later, turned back on again. In between, for the victim, time had stood still and memory remained intact. Nothing was added to it, but nothing was subtracted either.
We occasionally curse our memory when it lets us down. Yet overall, the powers of memory are prodigious. They enable a credible (though not necessarily objectively accurate) recollection of the life’s journey of a particular human brain, built up from numerous perceptions, feelings, thoughts, actions, and conversations with other brains – a series of complex experiences stored coherently, so it appears, and in a form that corresponds with their actual chronological order. At the same time, most of us cannot remember anywhere near everything that has happened to us. And whatever we imagine might be the benefits of having an eidetic or photographic memory, those who actually possess one know that it can be a blight and a handicap – in fact, in its most extreme manifestation, a crippling neurological disorder. Jorge Luis Borge wrote a disturbing short story, “Funes the Memorius,” about a young man who remembered every detail of his past:
He knew by heart the forms of the southern clouds at dawn on 30 April 1882, and could compare them in his memory with the mottled streaks on a book in Spanish binding he had seen once and with the outlines of the foam raised by an oar in the Rio Negro the night before the Quebracho uprising.Such exquisite retention might seem entirely fantastic. But the eminent neurologist A. R. Luria documented an actual case of total recall in his astonishing book, The Mind of a Mnemonist. The subject was a Russian man, Sherashevsky, who could remember – or, more to the point, could never forget – any detail, however small, of the experiences of his life: every sight, sound, taste, smell, and touch, every thought and impression, every way of looking at and analyzing a situation. And, of course, it was disastrous for him because he had no sense of discrimination. He could never focus on a specific problem or situation because as soon as he turned his attention to it, his mind was choked full or irrelevancies. Every trivial item spawned the recollection of a thousand others. He could not follow through a particular chain of reasoning, or make decisions, or take an interest in one topic over any other. In fact, he could not function normally at all and spent many of his days in abject depression and misery.
Recent research by scientists at the Cold Spring Harbor Laboratory, New York, suggests that photographic memory may have a genetic basis. Their work has centered on the so-called CREB gene in the fruit fly Drosophila. This gene is suspected of being the master switch that regulates other genes for synthesizing the key proteins involved in long-term memory. The Cold Spring Harbor team created a strain of fly carrying a modified form of the CREB gene which produced unusually large amounts of activator protein – the protein required for laying down memories. In addition, they arranged matters so that the altered CREB gene would only be turned on above 98 degrees Fahrenheit. Kept at room temperature, the genetically modified flies behaved normally, taking about ten training sessions to learn to avoid an odor associated with an electric shock. When warmed above 98 degrees, however, they learned the association after just one session. It seems likely that a similar “faulty” master gene, leading to the overproduction of activator protein, exists in people with exceptional powers of memory.
For survival reasons, a normal memory is selective and patchy, even if, to its owner, it doesn’t seem to be that way. The brain holds on to what it needs and quickly forgets what is irrelevant. Having organized itself, during childhood, around a particular worldview, the brain tends to consolidate mainly those memories that appear to fit in with and enhance this system of belief. Normal memory, then, is heavily biased toward a particular conception of reality. It is gappy, but good in parts, and may be exceptionally good with regard to some specific life episodes.
Just how good it can be was graphically demonstrated by the Canadian neurosurgeon Wilder Penfield and his team in Montreal in the 1950s. While operating on people under local anesthesia, in an effort to cure focal seizures by excising damaged brain tissue, Penfield would cut and turn back a portion of their skulls, expose their cerebral cortices, and then touch an electrical probe to specific points on the surface of the brain. This allowed him to identify and map regions of special importance, such as the language centers, that it was crucial were left intact by the surgery. Depending on exactly where on the cortex the mild pulsing current from the probe was allowed to flow, the patient would react in a highly specific, often comical way. He might utter a short, incomprehensible sound, or be prevented from saying anything at all. He might twitch the index finger of his left hand. And if the probe made contact somewhere on the lateral side of the temporal lobe, it would often trigger in the patient a particular, vivid reliving of a past event, as if the play button of a tiny video recorder had been pressed. Touching one spot on the cortex might cause a patient to hear her mother and father singing Christmas carols around the piano as they did in their youth; stimulation of another point nearby might spark off the recollection of a winter walk through fresh-fallen snow, or of a childhood incident in the schoolyard, or of an encounter with a menacing stranger. Each episode would seem strikingly realistic and detailed (much more so than a normal recollection), and each could be played again from the start, exactly as before, by an identical touch of the probe.
Our sense of being someone, a distinct person in the world, depends upon the unique chain of experiences that connects the moments of our lives – and which, through memory, we carry into the present. In his poem “The Mother’s Breast and the Father’s House,” B. Reed Whitmore writes:
warehouse devoted to documenting and buttressing the persistence of
you
Stuff with the dust of decades is in it
books, faces, tears, fears,
loves, hates, games, names
all in relation to you
colors, odors, textures, travel incredible distances with us
even the weakest among us is a sort of god of preserving of that which
would be wholly trivial if it were not ours ...
In the broadest sense, memory means more than just information stored in our heads. We “remember” about the past – even the very remote past – in our genes. And because of our onboard genetic program the stability of our selves is enhanced through the readily recognizable appearance, from day to day and year to year, of our bodies. Genes, too, inevitably have some influence on the basic architecture of our brains. But by far the most important contribution to personal identity and continuity comes from the memories our brains hold about what has happened to us during life.
Every day we gain some memories and lose others, have different sensations, and find ourselves in new situations, yet the brain copes with all of this change, adapts to it, and emerges at the end feeling as if it were the same person. This is its evolutionary legacy: the brain’s primary urge (like that of our body’s other systems) is to maintain the status quo. It works ceaselessly, automatically, to keep the impression it holds of itself constant and intact, whatever circumstances may prevail. To survive, biologically, means to stay the same, for if you change at all you become someone else, a new individual. So the brain is driven, relentlessly, to do everything it can to reinforce the feeling that it is unified, consistent, continuous. And in this mission, its ability to retain a chain of detailed past experiences is crucial.
Selves are defined by memories. But for many different reasons it is not always possible for a brain to maintain a complete or unbroken memory record. For instance, there is a certain kind of sleeping drug that induces a mild form of the effect known as retrograde amnesia. It does this by blocking the brain’s ability to transfer memories from short-term store to long-term store: if you take this drug you cannot, upon waking, remember anything that happened in the hour or so before you fell asleep. That hour, as far as you are concerned, may as well never have existed.
Imagine, now, that you have just taken a dose of this drug. For an hour you feel perfectly fine, in no way different than you did before. But, knowing what the eventual effect of the drug will be, you decide to write a detailed message to yourself. This describes all of the main events that happen during the next hour – the phone call from your friend, the sudden heavy shower of rain, the last minute goal you saw on TV that won the game for your team. Suddenly you feel an irresistible weariness creeping over you and decide it’s time to lie down. Eight hours later you wake up. The last thing you remember is taking the sleeping pill. But where did this note come from by the side of your bed? The handwriting looks familiar. It’s from you! Yet you have absolutely no recollection of having written it. You will never, at any moment during the rest of your life, remember having sent that message to yourself. It may as well have been written by a stranger. You are forever cut off from the thoughts and actions of the individual who lived through that missing hour of your life. He or she, though obviously physically continuous with you, is completely detached from your psychological continuum.
Blows to the head often produce a similar effect. Years ago, my son fell down while playing in the street one evening and banged his head against the curb. For a short time he lay unconscious before coming round, clearly still dazed and groggy, with an unfocused look in his eyes. He came inside, sat down, and suddenly looked in surprise at what he was wearing. “Where did I get these clothes?” he asked. In fact, they had been newly bought that afternoon. Yet to this day he cannot remember having gone shopping or anything else that he did in the four hours prior to his accident. His memories hold none of the experiences that his body and brain had during that time. As far as he is concerned now, it may as well have been someone else who had these experiences.
Most instances of amnesia are short-lived and have no important lasting effects on a person. But as a result of certain kinds of serious brain injury or disease, a profound and permanent form of amnesia may overwhelm its victim to the extent that he or she is unable to lay down any new memories at all. Such was the predicament of a certain musician who suffered from Korsakov’s syndrome. On one occasion, she had just completed, with three friends, a rendition of Beethoven’s Quartet in E Minor, Opus 59, No.2, having given a virtuoso performance on the violin. A few minutes later, the cellist urged that they try another piece to which the lady in question replied, “Let us play Beethoven’s E Minor Quartet, Opus 59, No.2.” An embarrassed silence followed, after which a member of the company gently pointed out what had happened.
In one of his essays, Oliver Sacks gives a moving account of another victim of Korsakov’s syndrome, whom he referred to as Jimmie G. When Jimmie first met Sacks in 1975 he was forty-nine years old but had no memory of anything that had happened for the previous thirty years (the damage to his brain having been caused by alcoholism.) To him it was still 1945, World War II had just ended, and he was an ebullient nineteen-year-old working aboard submarines in the U.S. Navy. A moment of crisis and panic ensued when Sacks asked Jimmie to look into a mirror and describe what he saw.
“Jesus Christ,” he whispered. “Christ, what’s going on?” What’s happened to me? Is this a nightmare?”
Two minutes later, having left the room, Sacks reentered to find Jimmie cheerful again, the mirror incident entirely forgotten, greeting him as if for the first time. He had absolutely no recollection of their earlier meeting or conversation. In his notes, Sacks wrote: “He is, as it were, isolated in a single moment of being, with a moat or lacuna of forgetting all round him.... He is a man without a past (or future), stuck in a constantly changing, meaningless moment.”
The problem for Jimmie and for others like him is not that life (in a caring, sheltered environment) need be impossible or even generally unpleasant, but that it is fraught with potential anomalies and contradictions. To believe with all your heart and mind that it is one time when it is really three decades later is to be in continual peril of confronting horrible, inexplicable inconsistencies. It is like living in an alien world – a world peopled by strangers who will always remain strange, and by relatives who appear unaccountably aged. Any moments of panic, it is true, are quickly and permanently forgotten – the syndrome at least ensures this degree of protection from itself. But to be in such a state, with no hope whatever of recovery, is to live permanently on the edge of an abyss of unreason.
We may think ourselves lucky that we are not afflicted with some such deep-seated neurological disorder. But none of us in truth stands far from the brink of personal chaos. Serious malfunctionings of the brain serve not to emphasize how much removed we are from the pathological but how frighteningly close we all stand to insanity’s edge. They expose the fragile basis of our lives: the extraordinary importance of a carefully ordered repository of facts in defining the beings that we are.
For victims of Korsakov’s syndrome, there is the continual problem of how to reconcile, how to make sense of, the crazy world in which they find themselves in terms of the only world they know – a world that may be many years out of date and that becomes increasingly anachronistic and irrelevant with each passing day. It is a problem that can be resolved or avoided in only one way: by confabulation, by making what (to others) seem facile or absurd rationalizations, “throwing bridges of meaning,” as Sacks says, “over abysses of meaninglessness.” The alternative, as when Jimmie was caught off guard and saw a middle-aged head on what he took to be a young man’s body, is total disorientation, disbelief, and denial. Doubtless we all have, at one time or another, felt a momentary rush of panic when, for example, we wake up thinking we are in one place when, in fact, we are elsewhere. For us, the crisis soon ends as memories flood back and we remember the recent chain of events and how we came to be where we are. But for the Korsakov victim there is no such prospect of relief – only the complete failure, a few minutes later, to remember even the state of panic or its cause. And there is the danger with every new moment and every new incident of the experience being repeated.
As we age, our memories, especially for details such as phone numbers, place names, and other odd snippets of information, inevitably falter as a result of a general, modest neurophysiological decline. Our brains lose about 15 percent of their mass between the ages of twenty-five and seventy. And in the hippocampus, a structure vital to the laying down of new memories, approximately five percent of the neurons die for every decade in the second half of life. But this gentle decline doesn’t seem to make much difference to us. We are born with a more than generous supply of around one hundred billion neurons (plus ten times as many glial or connecting cells), each of which becomes synaptically linked to as many as ten thousand of its neighbors. So we can well afford to lose several hundred million cells and their connections in a lifetime without being seriously inconvenienced. And, reassuringly, positron emission tomographic (PET) imaging has shown that the brains of spry eighty-year-olds are almost as active as those of people in their twenties. It seems that, along with many of the body’s other organs, the brain has immense physiological reserves – more than sufficient to be able to cope with what seems like an alarming loss of its component parts.
For most of us, then, memory loss in old age will amount to no more than a minor nuisance, like nearsightedness or stiffness in the joints. The continuity of our life’s story, the integrity of our brain’s gallery of remembrances, is essentially uncompromised so that we have no difficulty in retaining a stable impression of our own identities or those of people with whom we are familiar. However, for a significant percentage of the population (about 11 percent of those over sixty-five in the United States), there is the prospect in later life of a fairly rapid and catastrophic loss of cognitive functioning, including all levels of memory, due to various forms of dementia.
Because of the devastating effects it has on both the victim and the victim’s family, Alzheimer’s disease has justifiably become one of the most dreaded of terminal illnesses. It is like a cancer that affects the mind rather than the body. Typically within two to five years, it reduces a person from a state of near normality to one of total mental and physical disintegration and helplessness. By stages, Alzheimer’s patients become disconnected from their past. Their forgetfulness deepens until it becomes so profound that victims can no longer remember the names and faces of people they have known for many years, including their own children and spouses. Upon looking in a mirror they may be terrified to find that they can no longer recognize even their own faces. Unlike those afflicted by Korakov’s syndrome, Alzheimer’s sufferers see not an incomprehensibly aged version of themselves, but a total stranger. Yet their terror at being unable to recognize their own reflection is not due to a complete failure of the brain. On the contrary, it stems from the brain trying to struggle on; albeit beset with damage and decay, the brain still contrives to piece together and recall enough about the past and how the world should be that it inadvertently triggers a cataclysmic and irreconcilable inner conflict. The Alzheimer’s patient, even when the disease is far advanced, remembers (though perhaps only at a subconscious level) that a person is supposed to have a face and that one is supposed to know what one’s own face looks like. But the patient’s memory of how his of her face actually appears has been lost.
The human brain, shaped and honed by powerful evolutionary forces over many millions of years, is a born fighter. Without prompting, without our conscious intervention, it does everything in its power to promote and prolong the survival of the organism that houses it. To this end, it works ceaselessly, and for the most part successfully, to integrate, accommodate, and reconcile all of the information at its disposal. Even in terminal decline, with the bulk of its neural equipment smashed or faulty, it engages in a titanic but ultimately futile attempt to make up for the devastating effects of massive cellular damage. It even tries to rewire and repair itself from within.
At the University of California at Irvine, Carl Cotman and colleagues examined microscopically the brains of people who had died from Alzheimer’s disease and found that the loss of nerve cells in a region known as the entorhinal complex had been compensated for, to some extent, by the growth of other connections. Cells in the entorhinal complex analyze information about smells, but the region is also the site of the most important pathway from the cortex to the hippocampus (a structure crucial to the consolidation of new memories). In rats, cutting the pathway from the cortex to the hippocampus causes the input it receives from elsewhere in the brain (the so-called commissural-associational system and the septum) to rearrange themselves so that they partly take over from the layer of cells previously devoted to the terminals of the entorhinal cells. Cotman and his coworkers discovered that exactly the same kind of rearrangement took place in the hippocampi of Alzheimer’s patients.
The brain, then, does not submit easily. Unfortunately for someone in the final stages of dementia, this grim struggle to retain the maximum degree of cognitive capacity possible under the circumstances is not really desirable. To feel yourself inexorably slipping away, to be gradually cut adrift from everything you believed yourself to be, is surely worse than the actuality of death. And in this situation, the sooner the brain gives over the fight to retain its self the better.
An erosion of memory is an erosion of selfhood. Thus, the victim of Korsakov’s syndrome is still a person, but one whose evolution has come to an end – a person robbed of a future, trapped in stasis, without the possibility of further development or change. An Alzheimer’s patient, on the other hand, is a person in rapid, irreversible decline, a person whose death is occurring bit by bit, to the distress of everyone concerned, during life.
Such conditions graphically expose the importance of our memories, insubstantial things that they are, in binding us together and helping maintain the impression that we exist as coherent, enduring selves. Deprived of them, as the eighteenth-century Scottish philosopher David Hume remarked, “we are nothing but a bundle or collection of different sensations, which succeed each other with an inconceivable rapidity, and are in a perpetual flux and movement.” Hume recognized that personal identity – the one thing we so desperately want to believe is real – is no more than a masterful sleight of the brain. And modern neurology fully concurs.
We start out from the assumption that we are born, grow up, and live out our life as the same person. We have the strong impression of being a single, unchanging self. And all our dealings with other people and our conventional assumptions about our relationship to the world are predicated upon the notion that a fixed inner “I” exists – that personal identity is an inviolate fact.
Under equilibrium conditions – the normal, everyday situation in which changes to our warehouse of memories are small and gradual – the brain can easily sustain the illusion of self. So we who are this self are generally convinced of its permanence. But faced with a sudden rapid depletion of its memory store, through accident or disease, the brain can no longer cope. It becomes deprived of the means by which to project a convincing feeling of selfhood, a feeling that by its very nature must be based upon security and stability. This breakdown of the brain’s capacity to properly integrate the self triggers an inner conflict because the brain, compelled by its survival mandate, is bent upon avoiding change and reacts to it by generating the emotion of fear. In fact, the fear experienced by the Korsakov’s victim or the Alzheimer’s patient who can no longer recognize her own face or surroundings is simply a heightened form of the same fear we all feel when we contemplate the prospect of death. It is the raw fear of losing our selves.
Death would lose its sting if we had no fear of it. But how can we overcome this fear when confronted with the almost incontrovertible evidence that we are merely the narratives running inside our brains? It is bad enough that some of us may have whole sections of our life’s story ripped away through illness. But in death we all confront the ultimate form of amnesia – total neurological destruction and, with it, the ending of everything we are. How can we possibly discover in advance what this implies and how, when it happens, it will feel?