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Mind
Games
The 17th century scientist and philosopher René Descartes
saved science from religious domination by coming up with the theory of
dualism—dividing the body from the mind—but it meant that scientists spent
the next two centuries ignoring consciousness. Over the past 20 years there has
been a turnaround, as crusading researchers and thinkers focus on what many see
as the last big thing—the mind. How does the sludgy mass between your ears
decide what time to get up, what career to pursue, or whether to ponder a
cow-shaped cloud? Philosophers had the better of the debate in the past century, trying to
determine what objective truths could be stated about the mind, and behaviourist
psychologists threw the concept out altogether. But the scientists are back,
delving into neuron processes to determine what turns each person’s grey
matter into an experience of self. Neuroscientists, such as Oxford University professor Susan Greenfield,
have pushed deeper into the layers of activity between neurons, proposing that
our level of awareness comes from networks of neurons echoing around the links
between 100 billion matching cells like insects caught in a 3-D spider web: the
bigger the buzz, the higher the awareness. The professor of neurology at the University of Iowa, Antonio Damasio, is examining the evolutionary basis for emotions. Ole Paulsen at Oxford’s neuroscience department is looking at the formation of memory. The university’s Lawrence Weiskrantz implanted a silicon chip in the brain of a paraplegic and got nerve cells to attach directly to it, allowing the person to move a computer cursor using pure thought power. And pharmaceutical companies are pumping out pills such as Prozac that change the brain’s moods. It is in physics, however, that the most intriguing theorems are being developed. At the University of Arizona, an anaesthesiology and psychology professor, Stuart Hameroff, has taken the propositions of Oxford university mathematician Roger Penrose further, developing the Penrose/Hameroff Orchestrated Object Reduction (Orch OR) theory of quantum consciousness. In a nutshell, the theory suggests that inside each nerve cell, spindle-like microtubules (very tiny ropes of protein) exhibit quantum mechanical properties—dual wave/particle characteristics—holding two positions or configurations at the same time. These microtubules are able to dance in unison with thousands of others in a coherent network. Finally, the hybrid states collapse from their uncertainty of quantum entanglement into a singular, “classical” position, in the process forming conscious thought. Unlike the neuroscientific school, advocates of quantum consciousness hope it will provide the magic ingredient beyond chemical processes into the how and why of thinking. While dismissed out of hand in many quarters, the notions have escalated debate and direct research in attempts to prove (and deny) such propositions. The eminent physicist Paul Davies, who has written 25 books including The
Mind of God and is now at the Australian Centre for Astrobiology at
Sydney’s Macquarie University, says consciousness remains deeply mysterious.
Davies says a way to map the debate about the brain, the mind and consciousness
is to see it through the work of the ex-Adelaide mathematician David Chalmers,
now professor of philosophy at the University of Arizona, who talks of
“easy” and “hard” problems. The so-called easy problem is finding out which bits of the brain
correspond to particular mental states—feelings, sensations, thoughts, and
other reactions. “That is something we could, in principle, complete,”
Davies says. “We could imagine a big map of the brain and an understanding at
the electrochemical level of what is going on.” Some thinkers, including the Boston-based professor of philosophy at
Tufts University, Daniel Dennett, have argued that the brain processes inputs
like a Darwinian computer, by selectively sorting perceived information, and
that a separate consciousness outside the matrix of events and sensations of
life is an idle construct. “Subtract them, and nothing is left beyond a weird
conviction [in some people] that there is some ineffable residue of
‘qualitative content’ bereft of all powers to move us, delight us, annoy us,
remind us of anything,” Dennett says. Is a person’s experience of life more than the sum total of sensory
perceptions? Davies says it is here that the so-called hard problem emerges: how
can one describe in terms of neurons and synapses the blueness of blue or the
wetness of water? “Nobody really agrees on this, and there is debate whether
this is in fact a scientific problem,” Davies says. “Is it forever beyond
the realm of science to make a contribution to it?” Rodney Brooks would say so. Brooks is professor of computer sciences at
the prestigious Massachusetts Institute of Technology and head of its 250-strong
artificial intelligence lab. One of his projects is a humanoid robot that sees,
hears and feels. “Our robots have emotions, they respond emotionally,”
Brooks says. “They understand emotional responses in the same sense that a
child will react to an emotional response from an adult, such as anger,
encouragement or getting attention.” The robots emulate human responses via a replica visual cortex, motor
skill learning and language processing. But consciousness? “Any manifestation
of consciousness is an emergent property of simpler mechanisms in our robots,
but we are not saying they are conscious,” he says. Brooks’ book Flesh
and Machines rejects the quantum approach precisely because it is looking
for “magic.” Greenfield’s The Private Life of the Brain explains the early
view of the brain: that most animals share brain characteristics, including a
primitive brain stem surrounded by a limbic system. This system, including the
amygdala and cingulate cortex, cushions basic responses. When it is damaged,
people express inappropriate emotions. For example, Kluver-Bucy syndrome
patients exhibit high sexual drive towards anything nearby, including inanimate
objects. The cortex wraps the limbic system and is designated as the home of
cognitive processes, while the personality resides in the prefrontal cortex.
This gave birth to the lobotomy for dealing with the unruly mentally ill, and to
the view that the brain could be compartmentalised and a region for
consciousness located. At the Salk Institute in La Jolla, California, one of the DNA pioneers,
Francis Crick, belongs to an informal network known as the La Jolla Group on
Human Origins. It is not a typical conference—no papers are published—but
rather a cross-disciplinary forum interested in the basis of human life. A
meeting last month included a founding member, Derek Denton, whose work on
primary consciousness has stirred the evolutionary biology debate. Nobel
Laureate Gerald Edelman’s widely accepted view is that consciousness arose
through animals’ external perception of food and danger, an ability to form a
mental scene and then an intention to act. Denton, the founding director of the Howard Florey Institute in
Melbourne, has proposed that original or vegetative emotions are derived
internally, and has been using brain imaging of patients to find the
locations—deep in the midbrain—for the source of such urges as thirst,
hunger, or deprivation of air. On the pharmacological side, neuroscientist Candace Pert has identified a
peptide, the natural brain opiate enkephalin, which appears to be involved in
orchestrating emotions and health. It is clear there has been a lot of progress
on the so-called easy problem at the grey-matter synapse and neuron level. Greenfield, a neuro-pharmacologist, has moved from labelling brain
regions and prefers to describe the walnut-shaped brain, with its
cauliflower-appendage of cerebellum, as operating more like New York City. The
brain’s 100 billion neurons could be divided into boroughs, districts and
blocks. A room in a building on a block is like a neuron, which communicates
with other rooms in the city via messengers—transmitters that are received by
receptor chemicals—and inside each room are desk-bound synapses and ion
channel cupboards, with pumps for movement of electrical impulses which deliver
the required end responses. The brain’s ability to self-repair—for example, after a mild stroke—indicates it has plasticity way beyond the earlier categorisations. Far from being on the genetic determinist side of the nature/nurture debate, Greenfield considers the mind as “the seething morass of cell circuitry that has been configured by personal experiences and is constantly being updated as we live out each moment.” Emotions, Greenfield argues, are the building blocks of consciousness, which emerges as a series of waves of neuron networks that rise and fall according to the degree of awareness or stimulation. “One thing is clear: the brain doesn’t work like a digital computer.
It is swirling patterns of electrical activity. It has to do with patterns and
complexity,” says Paul Davies. Certainly there is a huge global effort to find
the bit where it happens, the NCC—the neural correlate of consciousness.
Davies says mapping ways in which neural processes correlate to conscious
outcomes is a reasonable approach. “But you are still stuck with the problem
of what is it about a particular complex electrical pattern that has thoughts or
sensations attached to it, let alone specific ones, like love or a sense of
greenness. What distinguishes those from the swirling electrical patterns in the
Victorian electricity grid, which presumably doesn’t have thoughts and
sensations attached to it? That is what a physicist would like to know. So it
still seems to me, as a physicist, deeply mysterious, the problem of
consciousness.” Alongside the Journal of Consciousness Studies, as a forum for
debate between disciplines, stand the Tucson dialogues. On Monday, the fifth
conference, titled “Towards a Science of Consciousness,” will fill the Music
Hall in the Arizona desert city with 1,000 scientists showcasing the latest
experimental and theoretical explanations for human experience. Davies has attended several Tucson conferences and is impressed by the
level of expertise that is being brought to bear on the subject. His former
Adelaide colleague, Chalmers, is associate director of the Center for
Consciousness Studies, which runs the Tucson events. He told The AFR Weekend
that this year there would be discussion about whether first-person methods of
observation could be developed and be as acceptable as traditional third-person
“observer” analysis of brain behaviour. Another track is sensory substitution: whether a device for a blind
person employing sound or taste can permit some level of seeing. “These people
report that they can see, they have perceptions of depth and so on, but the
$64,000 question is whether they are having the same sort of consciousness that
we have when we see, or whether it is something completely different,”
Chalmers says. On quantum consciousness (Chalmers’ critics call him a panpsychist), he
says there will be a session on a model for visual consciousness with Hameroff
and neurobiologist Nancy Woolf. Woolf is associate adjunct professor of
psychology at UCLA and was introduced to the work of Penrose and Hameroff by
Greenfield. Her work is in the neurotransmitter area of acetylcholine
regulators, and the actions of MAP2 (microtubule associated protein), but she is
attracted to the quantum model for its elegance and because it recognises time
as a variable enabling conscious “memory” to include past and future events.
“Perception is intertwined with memory and anticipation of the future,”
Woolf says. Hameroff’s notions echo the work of Austrian physicist Fritjof Capra,
whose Tao of Physics in the 1970s compared Heisenberg’s uncertainty
principle of quantum mechanics (you can’t know both the speed and position of
an atomic particle; the act of observing it will change either) with the cyclic
and balancing postulates of Eastern mysticism. Hameroff says he has read
Capra’s writings. “I think there are tremendous similarities between quantum
physics and spirituality. I think it’s just the deeper reality,” he says. The BBC asked him for comment when producing a series on out-of-body and
near-death experiences. Hameroff says: “What I told them was, if consciousness
is really a process in fundamental space-time geometry, then when the metabolic
drive pumping the coherence of the microtubules in the brain fails, the
information is not destroyed. You would think it would dissipate, but maybe
somehow it remains entangled and hangs together for a while, and then if the
brain is revived, it returns—which raises possibilities for afterlife.” In spite of a horde of critics, Hameroff is undeterred. “Time is on our
side. The classical approaches are going nowhere; they are flailing in terms of
explaining consciousness,” he says. “It is all more of the same hand waving,
emergence arguments, more ultra-reductionism—this part of the brain is
important, that part is not—with no attempt to deal with the enigmatic issues.
Nobody has a clue about the hard problem except to say that it emerges like a
rabbit out of a hat… we have testable predictions and the classical people
don’t.” And where, for Chalmers, is the progress on the hard question? “I think
it’s an awfully big question. We are making progress piece by piece. I don’t
think the hard problem is going to be solved anytime soon,” he concedes.
“But one of the things we are learning is that you can make progress toward a
science of consciousness without solving that problem. Basically, it is a
science of correlations. We get deeper and deeper systematic links between the
brain and consciousness. Because there is still this underlying mystery: why is
this link, this consciousness, there in the first place? At some point, someone
is going to want to say something pretty deep about that. But for now at least,
science is moving forward.” Hameroff says mainstream scientific
attitudes may well turn around with the development of quantum information
technology: quantum computers, quantum cryptography, quantum teleportation.
“As these things become more and more real, I think it would be more
inevitable for people to say, ‘Well, maybe our brains are like quantum
computers,’” he says. Davies’ characteristic caution about such speculation is evident: “I
don’t think it’s been proved that something funny couldn’t happen. I
remain open-minded but sceptical.” But he says consciousness could be worth a
bucketload in the race to create a machine that can truly reason. “This will
be a trillion-dollar business when it finally succeeds,” Davies says of the
global teams vying for first place. “If you could figure out that the brain is doing this
[behaving in a quantum fashion], you would be on to a winner. We are going to
know all about it if someone succeeds in demonstrating it.” The Australian Government has thrown funding in the ring for those
studying this field, giving $30 million to the Special Research Centre for
Quantum Computer Technology, which brings together teams from the University of
NSW, the University of Queensland and the University of Melbourne. Davies concludes that if Penrose and Hameroff are right, and there are microtubules in the brain that allow quantum coherence to be maintained through many cycles of information processing in a hot environment (the brain), “then that is exactly what the quantum computing people would need to make a functioning quantum computer, and that would be a revolution as great as the invention of the computer in the first place. So that is where the money would lie in this… if that is what you are after.” ***
*** *** Further reading: The Private Life of the Brain, by Susan
Greenfield (Penguin). © Australian Financial Review,
“Perspective,” Apr 6
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