I think that
consciousness is at least binary inasmuch as physically separate parts of the
gross nervous system are self aware in terms of each other. I particularly note the solar plexus brain
correspondence of profoundly automatic consciousness to a governing active
consciousness of the neo cortex.
Thus self awareness
begins with a necessary mutual awareness with neither particularly slaved to
the other as we unconsciously assume.
Yet there is a natural hierarchy of course to all this.
I think that such an
implied architecture makes consciousness inevitable. Besides, I have an issue with conclusions
based on Godel’s Theorem.
An intriguing
consciousness theory, but skeptics want evidence
Tanya
Lewis, LiveScience
June
28, 2013 at 2:54 PM ET
NEW
YORK — The idea that consciousness arises from quantum mechanical phenomena in
the brain is intriguing, yet lacks evidence, scientists say.
Physicist
Roger Penrose of the University of Oxford and anesthesiologist Stuart Hameroff
of the University of Arizona propose that the brain acts as a quantum computer — a computational machine
that makes use of quantum mechanical phenomena (like the ability of particles
to be in two places at once) to perform complex calculations. In the brain,
fibers inside neurons could form the basic units of quantum computation, Penrose
and Hameroff explained at the Global Future
2045 International Congress,
a futuristic conference held here June 15-16.
[ I am not convinced
that what we do is actually complex. I think instead we set up and compare
patterns - arclein]
The
idea is appealing, because neuroscience, so far, has no satisfactory
explanation for consciousness — the state of being self-aware and having
sensory experiences and thoughts. But many scientists are skeptical, citing a
lack of experimental evidence for the idea.
The
Orch OR model
Penrose and Hameroff developed their ideas independently, but collaborated in the early 1990s to develop what they call the Orchestrated Objective Reduction (Orch OR) model.
Penrose's
work rests on an interpretation of the mathematician Kurt Godel's incompleteness theorem, which states that certain results
cannot be proven by a computer algorithm. Penrose argues that human
mathematicians are capable of proving so-called "Godel-unprovable"
results, and therefore human brains cannot be described as typical computers.
Instead, he says, to achieve these higher abilities, brain processes must rely
on quantum mechanics.
But
Penrose's theory didn't explain how this quantum computing occurred inside
actual brains, just that the phenomenon would be needed to solve certain
mathematical equations. Hameroff read Penrose's work and suggested small
fibrous structures that give cells their structural support — known as microtubules — might be capable of
carrying out quantum computations.
Microtubules
are made up of units of the protein tubulin, which contains regions where
electrons are swirling around very close to each other. Hameroff proposed that
these electrons could become "quantum
entangled,"
a state in which two particles retain a connection, and an action performed on
one affects the other, even when the two are separated by a distance.
In
the Orch OR model, the mathematical probabilities that describe the quantum
states of these entangled electrons in microtubules become unstable in
space-time. These mathematical probabilities are called wave functions, and in
this scenario they collapse, moving from a state of probability to a specific
actuality. In this state, the microtubules in one neuron could be linked to
those in other neurons via electrical connections known as gap junctions. These
junctions would allow the electrons to "tunnel" to other regions of
the brain, resulting in waves of neural activity that are perceived as
conscious experience.
"Penrose
had a mechanism for consciousness, and I had a structure," Hameroff told
LiveScience.
Problems
with the model
Interesting as it sounds, the Orch OR model has not been tested experimentally, and many scientists reject it.
Quantum
computers — computers that take advantage of quantum mechanical effects to
achieve extremely speedy calculations — have been theorized, but only one
(built by the company D-Wave) is commercially available, and whether it's a
true quantum computer is debated. Such computers would be extremely sensitive
to perturbations in a system, which scientists refer to as "noise."
In order to minimize noise, it's important to isolate the system and keep it
very cold (because heat causes particles to speed up and generate noise).
Building quantum
computers is
challenging even under carefully controlled conditions. "This paints a
desolate picture for quantum computation inside the wet and warm brain,”
Christof Koch and Klaus Hepp of the University of Zurich Switzerland, wrote in
an essay published in 2006 in the journal Nature.
Another
problem with the model has to do with the timescales involved in the quantum
computation. MIT physicist Max Tegmark has done calculations of quantum effects
in the brain, finding that quantum states in the brain last far too short a
time to lead to meaningful brain processing. Tegmark called the Orch OR model
vague, saying the only numbers he’s seen for more concrete models are way off.
"Many
people seem to feel that consciousness is a mystery and quantum mechanics is a
mystery, so they must be related," Tegmark told LiveScience.
The
Orch OR model draws criticism from neuroscientists as well. The model holds
that quantum fluctuations inside microtubules produce consciousness. But
microtubules are also found in plant cells, said theoretical neuroscientist
Bernard Baars, chief executive officer of the nonprofit Society for Mind-Brain
Sciences in Falls Church, Va., who added, "plants, to the best of our
knowledge, are not conscious."
These
criticisms do not rule out quantum consciousness in principle, but withoutexperimental
evidence,
many scientists remain unconvinced.
"If
somebody comes up with just one single experiment" to demonstrate quantum
consciousness, Baars said, "I will drop all my skepticism."
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