Peering into the mystery of consciousness
Saturday, 1 September 2007
Syed Fattahul Alim
Consciousness is the attribute that draws the line between the world of the living and the non-living. But one may question whether the very primitive forms of life such as the protozoa possess what is usually understood by the term consciousness. The difference between the lower animals and the higher animals lies in their levels of consciousness. Precise calibration of various forms of life according to their consciousness is yet to be done. But even if such kind of calibration is ever carried out, would then the difference between humans and lesser animals turn out to be a matter of mere degree or is there something more between human and nonhuman forms of life more than just consciousness? Or in other words, does the simple term consciousness encapsulate everything about living things from amoeba to humans? What about intellect, ego, self, the first person I (who experiences what happens to the body), and the soul that human belief systems say distinguish people from lower animals? Researchers in neuroscience, however, are not willing to accept this kind of special attributes reserved for only humans that distinguish them from other animals. If anything, it is only consciousness in its different forms, they say. What is more, the neuroscientists are not even willing to give any special status to the identity factor, or I, who is in command of the person's body including consciousness.
According to them, there is no such thing as the core of consciousness or the identity of the person concerned. It is consciousness permeated all over the place passing for self, ego, I or soul or by whatever name one may call it. The experiments carried out on the brain has not so far found other essence other than essence called ego, self, or soul hiding somewhere within the human body. Paul Broks in New Scientist explains consciousness in the following words:
'As our post-millennial neuroscientists marvelled at the sparkling, dare I say spectral, patterns cascading from their high-resolution brain scanners, they were nagged by a mischievous question: who's running the show? How does the brain, with its diverse and distributed functions, come to arrive at a unified sense of identity? "Soul" doesn't figure in the lexicon of neuroscience, but what about the soul's secular cousin, "self"? Could we speak of a person's brain without, ultimately, speaking of the person? Was the self merely the sum of its cerebral parts? The illusion of the ghost in the machine was compelling - the natural intuition that somewhere in the shadows of the brain there lurks an observing "I", an experiencer of experiences, thinker of thoughts and controller of actions.
"How does the brain, with its diverse distributed functions, come to arrive at a unified sense of identity?"
This was hard to reconcile with the material facts (the vacant machinery that actually packs the skull) and it was plain to see that the mental operations underlying our sense of self - feelings, thoughts, memories - were dispersed throughout the brain. There was no homuncular assembly point where a little soul-pilot sat watching the dials of experience and pulling the levers of action. We were, neuropsychologically speaking, all over the place. And anyway, who did we think was pulling the levers in the little soul-pilot's head? If we found a ghost in the machine we'd have to start looking for the machine in the ghost.
Belief in an inner essence, or central core, of personhood, was called "ego theory". The alternative, "bundle theory", made more neurological sense but offended our deepest intuitions. Too bad, I thought. We should learn to face facts. The philosopher Derek Parfit put it starkly: we are not what we believe ourselves to be. Actions and experiences are interconnected but ownerless. A human life consists of a long series - or bundle - of enmeshed mental states rolling like tumbleweed down the days and years, but with no one (no thing) at the centre. An embodied brain acts, thinks, has certain experiences, and that's all. There is no deeper fact about being a person. The enchanted loom of the brain does not require a weaver.
Parfit devised a famous thought experiment. Imagine being teleported. A special scanner records the state of every cell in your brain and body and digitally encodes the information for radio transmission. Your body is destroyed in the process but reconstructed as soon as the signals are received and decoded at your destination. You "arrive" in precisely the same condition that you "left", identical in body, brain and patterns of mental activity. Your memories, beliefs, plans, skills and emotions are perfectly intact and you go about your business feeling and believing that nothing about you has changed in the slightest. It's just like waking from a dreamless sleep and getting on with the day.
If you are comfortable with this scenario then you should be comfortable with bundle theory. You appreciate that the observing "I" is no more than patterns of energy and information, which can be disrupted and reconstituted without destroying the self - because there is no self to destroy. The patterns are all. If, on the other hand, you believe that some essential "you" would be lost in the process then you are an irredeemable ego theorist. You believe that the reconstituted body is not "you" but a mere replica. Although the replica will know in its bones that it is the very person who stepped into the scanner at the start of the journey, and friends and loved ones will agree, you insist it could not be you because your body and brain would have been destroyed.
Incidentally, we see here a neat inversion of conventional thinking. Those who believe in an essence, or soul, suddenly become materialists, dreading the loss of the "original" body. But those of us who don't hold such beliefs are prepared to countenance a life after bodily death.
The philosophical speculations were intriguing, but the science of selfhood also had more practical concerns. This was the dawn of a new age in neuropsychiatry. The idea that certain forms of insanity were "disorders of the self" had been around for two centuries and more, but now the concept was being refined. The core deficits of autism and schizophrenia, for example, were revealed as faults in the brain circuits underlying personal awareness. This confederation of networks - frontal, limbic, temporal and cerebellar - orchestrated social cognition, from the analysis of gaze direction and facial expression to the deciphering of beliefs, attitudes, and intentions. In the process, it gave definition to that fundamental unit of social intercourse: the person. Just as the brain had evolved systems for guiding interaction with the physical world so, we rather belatedly realised, it had also evolved specialised mechanisms for enabling the interaction of "self" and "other".
The discovery of "mirror neurons" in the 1990s was a breakthrough in this regard. According to Vilayanur S. Ramachandran, one of the leading neuroscientists of the era, it was a discovery as significant in its way as Crick and Watson's decoding of the structure of DNA. Mirror neurons were activated not only in response to self-generated behaviour (reaching for an object, say) but also in response to actions performed by other individuals. Pain and emotional behaviour were similarly mirrored. The implication - that minds were neurologically "bridged" - was far-reaching, and mirror neurons rapidly took their place in theories of developmental psychology and moral behaviour.
The self had entered the neurobiological laboratory. Around this time it also became evident that, rather than being a single "ghost in the machine", we were a composite of two phantoms. The self of the present moment - the so-called "minimal" or "core" self - was, in the words of the neuroscientist Antonio Damasio, "a transient entity, recreated for each and every object with which the brain interacts". It was bound to brain systems involved in mapping and regulating body states. The other phantom was the "extended" self: a unified, continuous being journeying from a remembered past to an anticipated future, with a repertoire of skills, stores of knowledge and dispositions to act in certain ways. This "autobiographical" self emerged from language and long-term memory networks. Michael Gazzaniga, one of the great pioneers of cognitive neuroscience, pointed to a specialised left-hemisphere system - he called it "the Interpreter" - whose function was to wind disparate strands of brain function into a single thread of subjective experience. It worked by identifying patterns of activity across different brain modules and correlating these with events in the external world: it was a teller of tales.
The minimal self gave us our sense of location and boundary, and our intuitions of agency - the feeling that we exercise control over our actions. But these fundamentals of self-awareness were rather fragile constructs. Disturbances of temporal and parietal lobe function could cause profound dislocations of perception such as out-of-body experiences and autoscopic hallucinations (seeing one's body in extrapersonal space). Damage to the frontal lobes could disturb the sense of agency, with limbs developing a recalcitrant will of their own.
The extended self, too, was neurologically fragile. It could be gradually dismantled by dementia, or shattered by a sudden viral attack, the story of the self dissolved with the dissolution of memory. In contrast, a deep-brain stroke or injury to the frontal lobes could leave memory unaffected but recalibrate the machineries of emotion and temperament. The story continued, but the central character had changed beyond recognition. Sometimes the brain's story-telling mechanism itself broke down, resulting in the confabulation of fictional, often fantastical, autobiographical distortions. As science writer John McCrone put it, we are all just a stumble or burst blood vessel away from being someone else. Selfhood is malleable. That was the message.
Consciousness is the attribute that draws the line between the world of the living and the non-living. But one may question whether the very primitive forms of life such as the protozoa possess what is usually understood by the term consciousness. The difference between the lower animals and the higher animals lies in their levels of consciousness. Precise calibration of various forms of life according to their consciousness is yet to be done. But even if such kind of calibration is ever carried out, would then the difference between humans and lesser animals turn out to be a matter of mere degree or is there something more between human and nonhuman forms of life more than just consciousness? Or in other words, does the simple term consciousness encapsulate everything about living things from amoeba to humans? What about intellect, ego, self, the first person I (who experiences what happens to the body), and the soul that human belief systems say distinguish people from lower animals? Researchers in neuroscience, however, are not willing to accept this kind of special attributes reserved for only humans that distinguish them from other animals. If anything, it is only consciousness in its different forms, they say. What is more, the neuroscientists are not even willing to give any special status to the identity factor, or I, who is in command of the person's body including consciousness.
According to them, there is no such thing as the core of consciousness or the identity of the person concerned. It is consciousness permeated all over the place passing for self, ego, I or soul or by whatever name one may call it. The experiments carried out on the brain has not so far found other essence other than essence called ego, self, or soul hiding somewhere within the human body. Paul Broks in New Scientist explains consciousness in the following words:
'As our post-millennial neuroscientists marvelled at the sparkling, dare I say spectral, patterns cascading from their high-resolution brain scanners, they were nagged by a mischievous question: who's running the show? How does the brain, with its diverse and distributed functions, come to arrive at a unified sense of identity? "Soul" doesn't figure in the lexicon of neuroscience, but what about the soul's secular cousin, "self"? Could we speak of a person's brain without, ultimately, speaking of the person? Was the self merely the sum of its cerebral parts? The illusion of the ghost in the machine was compelling - the natural intuition that somewhere in the shadows of the brain there lurks an observing "I", an experiencer of experiences, thinker of thoughts and controller of actions.
"How does the brain, with its diverse distributed functions, come to arrive at a unified sense of identity?"
This was hard to reconcile with the material facts (the vacant machinery that actually packs the skull) and it was plain to see that the mental operations underlying our sense of self - feelings, thoughts, memories - were dispersed throughout the brain. There was no homuncular assembly point where a little soul-pilot sat watching the dials of experience and pulling the levers of action. We were, neuropsychologically speaking, all over the place. And anyway, who did we think was pulling the levers in the little soul-pilot's head? If we found a ghost in the machine we'd have to start looking for the machine in the ghost.
Belief in an inner essence, or central core, of personhood, was called "ego theory". The alternative, "bundle theory", made more neurological sense but offended our deepest intuitions. Too bad, I thought. We should learn to face facts. The philosopher Derek Parfit put it starkly: we are not what we believe ourselves to be. Actions and experiences are interconnected but ownerless. A human life consists of a long series - or bundle - of enmeshed mental states rolling like tumbleweed down the days and years, but with no one (no thing) at the centre. An embodied brain acts, thinks, has certain experiences, and that's all. There is no deeper fact about being a person. The enchanted loom of the brain does not require a weaver.
Parfit devised a famous thought experiment. Imagine being teleported. A special scanner records the state of every cell in your brain and body and digitally encodes the information for radio transmission. Your body is destroyed in the process but reconstructed as soon as the signals are received and decoded at your destination. You "arrive" in precisely the same condition that you "left", identical in body, brain and patterns of mental activity. Your memories, beliefs, plans, skills and emotions are perfectly intact and you go about your business feeling and believing that nothing about you has changed in the slightest. It's just like waking from a dreamless sleep and getting on with the day.
If you are comfortable with this scenario then you should be comfortable with bundle theory. You appreciate that the observing "I" is no more than patterns of energy and information, which can be disrupted and reconstituted without destroying the self - because there is no self to destroy. The patterns are all. If, on the other hand, you believe that some essential "you" would be lost in the process then you are an irredeemable ego theorist. You believe that the reconstituted body is not "you" but a mere replica. Although the replica will know in its bones that it is the very person who stepped into the scanner at the start of the journey, and friends and loved ones will agree, you insist it could not be you because your body and brain would have been destroyed.
Incidentally, we see here a neat inversion of conventional thinking. Those who believe in an essence, or soul, suddenly become materialists, dreading the loss of the "original" body. But those of us who don't hold such beliefs are prepared to countenance a life after bodily death.
The philosophical speculations were intriguing, but the science of selfhood also had more practical concerns. This was the dawn of a new age in neuropsychiatry. The idea that certain forms of insanity were "disorders of the self" had been around for two centuries and more, but now the concept was being refined. The core deficits of autism and schizophrenia, for example, were revealed as faults in the brain circuits underlying personal awareness. This confederation of networks - frontal, limbic, temporal and cerebellar - orchestrated social cognition, from the analysis of gaze direction and facial expression to the deciphering of beliefs, attitudes, and intentions. In the process, it gave definition to that fundamental unit of social intercourse: the person. Just as the brain had evolved systems for guiding interaction with the physical world so, we rather belatedly realised, it had also evolved specialised mechanisms for enabling the interaction of "self" and "other".
The discovery of "mirror neurons" in the 1990s was a breakthrough in this regard. According to Vilayanur S. Ramachandran, one of the leading neuroscientists of the era, it was a discovery as significant in its way as Crick and Watson's decoding of the structure of DNA. Mirror neurons were activated not only in response to self-generated behaviour (reaching for an object, say) but also in response to actions performed by other individuals. Pain and emotional behaviour were similarly mirrored. The implication - that minds were neurologically "bridged" - was far-reaching, and mirror neurons rapidly took their place in theories of developmental psychology and moral behaviour.
The self had entered the neurobiological laboratory. Around this time it also became evident that, rather than being a single "ghost in the machine", we were a composite of two phantoms. The self of the present moment - the so-called "minimal" or "core" self - was, in the words of the neuroscientist Antonio Damasio, "a transient entity, recreated for each and every object with which the brain interacts". It was bound to brain systems involved in mapping and regulating body states. The other phantom was the "extended" self: a unified, continuous being journeying from a remembered past to an anticipated future, with a repertoire of skills, stores of knowledge and dispositions to act in certain ways. This "autobiographical" self emerged from language and long-term memory networks. Michael Gazzaniga, one of the great pioneers of cognitive neuroscience, pointed to a specialised left-hemisphere system - he called it "the Interpreter" - whose function was to wind disparate strands of brain function into a single thread of subjective experience. It worked by identifying patterns of activity across different brain modules and correlating these with events in the external world: it was a teller of tales.
The minimal self gave us our sense of location and boundary, and our intuitions of agency - the feeling that we exercise control over our actions. But these fundamentals of self-awareness were rather fragile constructs. Disturbances of temporal and parietal lobe function could cause profound dislocations of perception such as out-of-body experiences and autoscopic hallucinations (seeing one's body in extrapersonal space). Damage to the frontal lobes could disturb the sense of agency, with limbs developing a recalcitrant will of their own.
The extended self, too, was neurologically fragile. It could be gradually dismantled by dementia, or shattered by a sudden viral attack, the story of the self dissolved with the dissolution of memory. In contrast, a deep-brain stroke or injury to the frontal lobes could leave memory unaffected but recalibrate the machineries of emotion and temperament. The story continued, but the central character had changed beyond recognition. Sometimes the brain's story-telling mechanism itself broke down, resulting in the confabulation of fictional, often fantastical, autobiographical distortions. As science writer John McCrone put it, we are all just a stumble or burst blood vessel away from being someone else. Selfhood is malleable. That was the message.