"Dr. Hameroff's research for 35 years has involved consciousness - how the pinkish gray meat between our ears produces the richness of experiential awareness. Studying anesthetic gas mechanisms, he focused on how quantum effects control protein conformational dynamics. Following an interest which began in medical school in the computational capacity of microtubules inside neurons, Dr. Hameroff teamed up with the eminent British physicist Sir Roger Penrose in the early 90s to develop a highly controversial theory of consciousness called orchestrated objective reduction (Orch OR). Dr. Hameroff began the international, interdisciplinary conferences on consciousness (Toward a Science of Consciousness) as Director of the Center for Consciousness Studies at the University of Arizona. He has published five books and well over 100 research articles, and appeared in the film What the Bleep do we know!!??"
Ben Dench: Could you briefly explain
the difference between the quantum
theory of consciousness that you
have proposed and the neurocomputational theory of
Stuart Hameroff: First of all, we agree with the neurocomputational theory, just not that it accounts completely for consciousness. Neurocomputation implies that each neuron is a fundamental unit directly analogous to bits and switches in computers. Now we all do a lot of behaviors--sensory processing, driving a car, and so forth--which may or may not be conscious. If they are not conscious--if we are on auto-pilot, then those non-conscious behaviors and processes can be accounted for by neurocomputation. So if you see the brain as a computer at the neural level -- neurocomputation - you can indeed explain non-conscious, auto-pilot functions and behaviors. But consciousness is missing. I think consciousness is something additional to normal cognitive processes. So we don't reject neurocomputiation--in fact we need it. We just say it doesn't account for consciousness. Something else is needed.
Most people would say that
consciousness emerges as a higher order property, an emergent
phenomenon, from complex computation. So if there is sufficiently
complex neurocomputation, consciousness emerges as a novel property.
That's kind of the conventional wisdom, but there's no reason
to think that's true. It's kind of the default position. And in
fact consciousness seems to move around the brain, while the
neurocomputation continues all through the brain.
When I drive to work every day along the same route, my mind often wanders. I am driving perfectly well on auto-pilot as long as everything is routine. I am conscious of what I will be doing when I get to work, the game I watched last night, my family, etc. But if a light flashes or a horn sounds, my consciousness returns immediately to driving. Studies on mind wandering show neuronal activity literally moving around the brain.
Here's another metaphor. Imagine a passenger airplane cruising at 35,000 feet.
The pilot puts the plane on auto-pilot and takes a nap, or goes to the bathroom, perhaps chats with the stewardess in the galley. Everything is fine until there is turbulence and he/she returns to the cockpit and resumes conscious control of the plane from the auto-pilot.
So consciousness is like an added
feature to neurocomputation. I think it occurs in a particular group
of neurons and glia defined by a spatio-temporal envelope moving
around the brain. Within the envelope is consciousness, mediated by
quantum computations in microtubules. All the other neurons outside
the envelope continue to process and compute in a non-conscious way.
So our theory is an added feature to neurocomputation, and doesn't
conflict with it in any way, except to say that neurocomputation per
se does not account for consciousness.
The conscious pilot model, which I published earlier this year, describes a spatio- temporal envelope of synchronized neurons and glia defined by sideways connections through gap junctions. As gap junctions open and close, the synchrony moves around the brain. Obviously neurons themselves don't move, just the synchronized zone. Inside the zone, quantum computation defined by our Orch OR model occurs as an added feature mediating consciousness.
SH: Yes. As a matter of fact, do you know the Lifeboat Foundation? They're related to the Singularity Summit. I'm not well received by AI people because I think the level of complexity to achieve brain equivalence has to include the microtubule level, so that pushes their goalpost for brain equivalence in computers way down the road. Be that as it may, they did invite me to speak at the Singularity Summit in October, and then they asked me to join this Lifeboat Foundation, which is basically to guard against any future disaster of any kind, and they talk about different things.
I'm an anesthesiologist, and a couple weeks ago, in the operating room, we were doing a routine case, we were just kind of talking, and one of the nurses mentioned a book called Patient Zero about something that turns people into zombies. And a zombie is a non-conscious entity, in the movies, but there are also philosophical zombies that Dave Chalmers came up with. And I think that every part of the brain that doesn't have the consciousness pilot is a zombie.