From: Kharin (kharin@kharin.com)
Date: Fri Oct 31 2003 - 05:13:21 MST
(Filed: 29/10/2003)
It is a riddle that still foxes scientists – where in the brain our sense of self is born. Paul Broks reports
Science, having done away with the soul, has lately been turning its gaze to the soul's secular cousin: the self. There is no ghost in the machine, it is agreed, just a machine.
The challenge is to specify which operations of the machine (that is, the brain) give rise to the sense of self. According to the neuroscientist Vilayanur Ramachandran this is the greatest scientific and philosophical riddle of all. Others see it as a doomed quest. The self, like the soul, is an illusion; the brain scanners are tracking a chimera.
There is nothing illusory about the effects of brain damage, however, and although any illness can affect the way we see ourselves, neurological disease sometimes penetrates the very substructures of the self - the brain systems controlling long-term memory, for example, or those that regulate emotion and bodily awareness.
As a clinical neuropsychologist, helping patients and those around them come to terms with the psychological consequences of brain disorder, I see problems of self-awareness and personal identity not just as conundrums of science and philosophy but as matters of real practical concern. At the same time, the experiences of patients may illuminate some of the deepest problems of philosophy.
"I know that I exist," said Descartes, "the question is, what is this 'I' that I know?"
One of my patients, Stella, has temporal lobe epilepsy and, when her brain misfires, she is thrown into a similar quandary. Her seizures start with a feeling of detachment. She might be walking down the street. She might be at home. It can happen anywhere. Objects and people seem brighter than usual, more alive, but at the same time utterly unfamiliar. She knows what's going to happen next, and she tries to resist, but usually it happens anyway. "I sort of evaporate."
Evaporate? "I have no idea who I am." She does not know her name and has no recollection of her personal history, or any appreciation of where she is, or what she is supposed to be doing. She has become a point of subjective experience, devoid of identity. These episodes are brief and, within a few minutes, she seeps back into herself.
Stella's loss of identity does not strip her entirely of a sense of self. The "evaporations" seem to lay bare what is sometimes called the "minimal" or "core" self - the self of the present moment. In the words of neurologist Antonio Damasio, this core self is "a transient entity, recreated for each and every object with which the brain interacts". It is the most primitive, and robust, feature of self-awareness.
Yet, in rare cases, even the core self seems to dissolve. Another patient believed that she had ceased to exist. "Am I dead?" she tentatively asked. I assured her that she was alive, that we were on the ward chatting and drinking tea. She was unconvinced.
"But what about you?" she said. "Are you real?" This is Cotard's syndrome , a nihilistic delusional state, which may be due to a neurological decoupling of feelings and thoughts. Thinking that one exists is not enough, the notion must also be felt: "I feel I think, therefore I am.''
Ordinarily, when we think of ourselves we have something other than the primitive, core self in mind, something closer to the notion of "personal identity". We think of a more elaborate entity journeying from a remembered past to an anticipated future, replete with knowledge, recollections, and dispositions to act in certain ways. Philosophers call this the "extended" or "autobiographical" self. It is more fragile than we care to think.
There are many ways of wiping the neural records of a life: the slow progression of Alzheimer's disease crowding the cortex with plaques and tangles, the blitzkrieg of a viral encephalitis blasting through the memory circuits of the temporal lobes, the deep-brain booze-wreckage of alcoholic Korsakoff's syndrome . Yet, in some respects, the autobiographical self is also remarkably robust.
Judy came round from a disturbed sleep to find that a stroke had reset her brain's calendar 23 years back to 1976, leaving her with no memory of the intervening time. She believed she was in her thirties, rather than her sixties. The strange man in the room turned out to be her second husband. He held up a newspaper, pointing out the date at the top of the page and Judy demanded a mirror. Her face was wrinkled, and her hair was short and grey.
However, despite the gross autobiographical discontinuity, integrity of personality was preserved. She was "the same Judy", if rather older and greyer. In time she adjusted to her new circumstances and came to accept the re-drafting of her story.
Other forms of neurological disorder have an opposite effect, leaving memory more or less intact, but distorting the person, in essence. Driving home from work one night, Jeff was hit head-on by a car. I remember him on the ward, furiously wrenching his neck. "Get this head off me," he kept saying. "Get it off, it's the wrong one." The image haunts me. It contains a desolate truth. It was the wrong head.
The original housed the steady dispositions of a loving husband and father, the knowledge and skills of an educated man. His damaged brain is now a place where thoughts and urges roam untethered, provoking dark turns of mood and, sometimes, spiteful outpourings of abuse. "I tell myself it's not really Jeff," his wife says, but she stands by him out of the dutiful conviction that, at some level, it is really Jeff.
Descartes believed that our capacity for self-awareness was due to the possession of an immaterial soul. I have long since rejected this myth. (Are we to imagine a mutilation of Jeff's soul as well as his brain - and, if not, what does the pristine soul make of Jeff's disturbed behaviour?).
I find it harder to shake off "the myth of the self", an inner "I" monitoring the screens of perception, orchestrating thoughts and actions. But neuroscience reveals that the mental processes underlying our sense of self - feelings, thoughts, memories - are scattered through different zones of the brain. There is no special point of convergence, no inner sanctum of the ego. And neurological case studies reveal "the self" to be multifaceted and fragile. To paraphrase the science writer John McCrone, we are all just a stumble or a burst blood vessel away from being someone else.
Dr Paul Broks of Plymouth University is the author of Into the Silent Land (Atlantic Books), which is available for £12.99 + £2.25 p&p. To order, call Telegraph Books Direct on 0870 155 7222.
Tickets for his Last Word lunchtime lecture (12.45-1.45pm) on Nov 13 at the Royal Geographical Society, London, usually cost £21 but are available to Telegraph readers for £8. For tickets, tel; 020 7792 9512. Quote Telegraph Science. The same discount is available for the lunchtime lecture on Nov 11 by Prof Howard Gardner of Harvard University, who will discuss his theory of multiple intelligence and success at work.
www.lastwordlectures.com
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