Ch. 3: MIND, BRAIN, AND QUANTUM PHYSICS

Quantum Physics

There are several unique experimental quandaries in the physics of the late 1800ís leading to the overturning of the monopoly of physical theory by classical physics. The resolution of these quandaries led to the introduction of quantum theory into modern physics by Einstein, Bohr and others. Based on the revolution in thought brought about by these experiments, we were no longer able to think of the world as wave or particle, matter or energy, subject or object. We were made aware of the fact that light, accepted as waves, now had particle qualities, and electrons, accepted as particles, had wave qualities. At about the same time, Heisenberg gave formal proof that because of the inherent properties of nature, we are not capable of measuring precisely both position and velocity of particles (not because of technical insufficiency), but only probabilities of position and velocity. The deeper shock here is that the particle itself, in one environment, actually lacks definite position, and in another environment lacks velocity, thus introducing a grave problem for physics--how can we measure anything reliably, knowing our measurements (the environment in which we place the particle) alter the object under scrutiny (the particle), thus altering the measurements we are making, thus altering the object under scrutiny,etc?

Other developments pushed us still further away from the classical, and even the relativistic picture of reality, two of which were in response to the famous EPR (Einstein-Podolsky-Rosen) paper.1 The first, and most well-known is the Schroedinger cat paradox. Given that quantum states are superpositions of probability distributions, and these states are only reduced on the act of observation, 2 Schroedinger proposed a cat in a box, sealed in with radioactive material (i.e., a material which emits high energy particles) and a Geiger counter connected to a vial of cyanide. If the radioactive material decays (emits a particle), the Geiger counter will go off ("click"), and the cyanide vial will break, killing the cat. The paradox, using the Schroedinger equation, is that the cat is in a linear superposition of both being dead and being alive at the same time, until the box is opened, the cat is observed, and the "probability wave is collapsed" (i.e., "reduced"), thereby producing a cat that is suddenly either dead or alive. Thus, according to Shroedingerís equation, until the box is opened and the cat observed (i.e., the "wavefunction is collapsed") the cat is both dead and alive at the same time. It is only when the box is opened that our act of observing causes the cat actually to become dead or alive. But can quantum probabilities be used to describe macroscopic systems, such as dead or alive cats? Those who say yes are stuck with a cat that is at the same time both dead and alive, an obvious paradox. Those who say no need to explain what went wrong with the Schroedinger equation, which has consistently proven itself to be a valid and useful equation.

The second development is the EPR paradox, and became the basis for Bell's theorem, which states (at a very basic level) that any equation which adequately explains behavior at the classical level, cannot explain behavior at a quantum level, when discussing causation and action at a distance. Normally we see a universe of cause and effect based on physical contact or fields which are spatially and temporally connected. For example, a billiard ball doesnít move until another ball physically contacts it; likewise, the light of the sun, which is at a distance of approximately 93.2 million miles from the earth doesnít reach our eyes instantaneously. It takes about eight minutes after it leaves the sun, even though light moves as fast as anything in the universe possibly can. The situation is very different in the realm of quantum physics.

Briefly, according to the EPR paradox, two "entangled" particles respond simultaneously to a reduction of just one of the particles, regardless of the distance separating the two particles. 3 A far-fetched macroscopic example of this would be if two eggs were thrown out of a rapidly spinning bowl (we will say these eggs are "entangled"). One egg has four feet to fall before it is splattered on the sidewalk, while the second egg has eight feet to fall. In the quantum physics world, at the exact moment the first egg is splattered, the second egg also splatters, even though it hasn't hit the ground yet. This is an example of the instantaneous, non-local causation found at the quantum level. The point of describing these events which seem very contrary to our common experience with the world is to help us see that when considering how the mind is produced by the brain, we might not be able to rely on common-sense ideas.

Neurophysiology and Mind

Mind is not localizable in any one part of the brain, as we have already seen. All attempts to discover one single area or even a few areas of the brain controlling "consciousness" have failed (see Appendix C for definitions of mind and consciousness). Certain areas contribute more, however, than others, to "higher" functions, such as the cortex, which processes language, sensation (touch, taste, vision, etc.), computation, creativity and motor control. Damage to various areas of the cerebrum and even removal of certain areas can often be overcome, therefore one can conclude the cerebrum is not the "seat of mind."

The reticular formation is the seat of the conscious state. If the reticular formation is damaged, the person becomes unconscious, and often enters into an irreversible coma. Some have proposed this area as the foundation for mind, since general excitability, awareness, and to some extent, pain are processed here. But this also is not the seat of the mind. Incidents are not uncommon in which persons in reticular formation comas have recovered, and they remember incidents which occurred in their presence while they were in the comatose state. Therefore, though their environmental interaction was disabled and other functions were diminished, they were still able to process and store information, and usually even with an affective component (anger at discouraging doctors, helplessness at their own state, love for significant others who talked to them and cared for them, etc.).

Finally, both memory function and emotions are vital to mind. The limbic system contains key brain structures involved with long-term memory and emotional determinacy (especially the hippocampus and amygdala) . Without long-term memory and emotion, there is no way to develop a consistent view of oneself, of the world around us, or an affective perspective on either. Thus there would also be no way to develop personhood or interpersonal relationships, two key elements in the development of mind. The limbic system, however, is also not the housing of the mind. Though severe deficits in "apparent personhood" occur when the hippocampus is damaged, any memories incurred prior to the damage are still intact, therefore the personhood of the individual remains, though its continued growth is severely stunted. Thus a major problem with Alzheimer's patients is that their personalities remain intact throughout the major portion of the disease, but their capacities to learn and to retrieve recent memories become severely limited. Similarly, with affective disorders that alter amygdala function, few people would call other humans "mind-less" because they have difficulty controlling or producing emotions. Thus, these two areas are also not the housing for mind.

Though the mind cannot be localized in any one brain structure, this neither requires nor allows us to ignore the brain in the study of mind (as many psychologists and cognitive scientists attempt). The function, or at least the expression of mind, is altered when the brain is damaged. One might say that while the brain may not "house" mind, it might be a kind of transducer, 4 from mind to behavior and thought. But one still has to answer the question of where this function is localized--what is the "pineal gland" for today (Descartesí point of contact between mind and brain)? It is my contention that no point of contact will be found, because mind is a product of brain, not a product of any particular point, but of the brain as an holistic system. 5

In studying the mind, it is important for us to have a basic idea of how the brain itself works. Different areas of the brain do different things, as we have already seen. Each of these separate areas has basically the same components controlling them--neurons. Unfortunately for mind speculators, there is no magical, inexplicable difference between the neurons and all other cells in the body. The only major difference is that the neuron has developed excellent abilities for intercellular communication. Each neuron has several, if not hundreds of, dendrites to receive information from other neurons, capillaries, etc., and one larger extension, the axon, by which it transmits information. At every junction between neurons (dendrite-axon, axon-axon, dendrite-cell body, etc.) there exists what is called a synapse (see Appendix A.1). The synapse is an histologically distinct area composed of neurotransmitters contained in vesicles (the vesicle is a small membrane-bound structure that stores and transports neurotransmitters), a paracrystalline, presynaptic grid, a postsynaptic cleft, and a narrow gap (the actual synapse). When a neuron wants to transmit information, it creates an electro-chemical pulse at the root of the axon, the axon hillock. This pulse travels down the axon where it reaches the presynaptic terminal and depolarizes the presynaptic grid. When the presynaptic grid reaches the critical threshold of activation, it releases the vesicles by exocytosis, which then cross by Brownian motion across the synapse to be captured by the postsynaptic cleft. At absorption, the vesicle releases its neurotransmitters and thus gives information to the postsynaptic neuron. When the postsynaptic neuron receives enough information from various presynaptic neurons, it then generates another electric pulse, thus starting the process over again until finally enough neurons are activated to produce a macroscopic result (motion, perception, etc.). This is one of the key levels where computational quantum mechanics has applicability to neurophysiology.

The most important contribution to a systematic study of quantum physics and neuro-physiology that I have found is the work of Sir John Eccles. One of the first problems he deals with is whether the synapse can theoretically be a site of quantum effects. He cites the work of Margenau (Eccles 1986:418) for his results, and shows that because of the small size of the synaptic vesicle there is just enough quantum instability to allow "tunneling" 6 to occur across the presynaptic membrane. Further, Eccles proposes a mechanism which brings the presynaptic vesicular grid into a "metastable state" conducive to discharge of the vesicles. Since this trigger is semi-unstable it allows for "a quantum mechanical tunnelling process through the barrier" (Beck and Eccles 1992:11,358). 7

Quantum Physical Analogies to Mind

Stapp and Bohm attempt to make a case for the holistic structure of mind, and to compare that to quantum mechanics. Most people think of consciousness as a unified phenomenon, not fragmented and disjointed. Once people consider the apparent fragmentation of the universe and the fact that it is entirely made up of small disjointed particles, they begin to see the stark contrast between the external reality and our own perception of it. For example, we all assume causality. Just because a billiard ball strikes another, what causes us to perceive the "flow" of events that the first ball causes the other ball to move? Certainly there is physical contact, but why do we assume one caused the other? We would not go on to assume that if the same ball were to strike a bowling ball, the bowling ball would therefore roll. Thus we have to postulate concepts such as mass and velocity to explain the observed results quantifiably, which, as we know, generally work out very predictably and accurately. The point is that the flow we observe as integral and continuous is not provable in any a priori sense (ŗ la Hume), even though the calculations work well, and the events "appear" to be integral and continuous.

As a further example, take such aesthetic phenomena as musical works, paintings, and literature. Though individual musical notes stir no great emotions in most people, put certain notes together to make chords, and put those chords in certain patterns, and these fluctuations of air molecules are "magically" transformed into events which create joy, sorrow, anger, etc., in the hearer, who perceives the piece as a "flowing," unified whole. The same effect occurs with stipple paintings, such as by Monet, where individual points of chemicals come together to create a single picture unified theme. Further, any kind of writing or prose where individual marks of ink (letters) come together to create a unified, continuous stream of ideas and images. These concepts are typically even more striking when one understands the neurobiology of the visual, tactile and aural systems. Here millions of individual mechanical, vibrational, and light signals are transduced into biochemical-electrical impulses, then projected to various areas in the brain allowing us to perceive a steady "stream of consciousness" which we call the universe.

Bohm cites two reasons for this appearance of holism (Bohm 1990). The first relates to Bell's theory and non-local action. Given the complex network of neurons in the brain and the time-limiting factors such as electro-chemical generation, Brownian motion, etc., one might expect a more fragmented perception of time. One explanation for this lack of fragmentation is that particles in different areas of the brain may respond simultaneously to an event, thus speeding up the process of integrative perception/cognition. The second explanation set forth by Bohm is analogous to superconductivity. 8 The particles in the brain, similar to those in superconductive metals, "move together in an organized way" (1990:280) and thus all of the separate particles in the system act together in a unified, responsive manner (see also Jirsa 1994:27-35; and Jibu 1994:195-209). This, also, is related to Bell's theorem (instantaneous action at a distance), but is an extension and possible practical, systemic effect of the consequences of Bell's theorem--"the quantum potential for the whole system constitutes a non-local connection that brings about the above described organized and orderly pattern of electrons moving together without scattering." Bohm's conclusion is that mind is this quantum potential for organization. Anything capable of guiding the mass of chaotic "information" of a system and correlating that into an integrated movement on the macroscopic level is said to be a "mental" event of mind, even in the case of metallic superconductivity. Active information, to Bohm, then becomes the bridge between the mental and the physical in nature, and information is what we are perceiving when we say "I think such-and-so," or "I feel such-and-so."

Stapp also claims "nothing in classical physics can create something that is essentially more than an aggregation of its parts," but a quantum actual event "creates a single new actuality by grasping and combining together into a unified new ontological whole various diverse aspects of the prior situation" (Stapp 1991:1470). He goes on by explaining the importance of quantum actual events is their integrative character "in the sense that the information pertaining to the many diverse points [in a quantum equation] are combined together to give the new state." The question Stapp uses to bridge the gap between mind and the above formula is: what does the Schroedinger probability represent?

Stapp mentions Bohm's "pilot-wave" ontological explanation,9 which, in a sense, inverts common conceptions about physics. Stapp rejects Bohm's theory in its pure form because consciousness has previously had no place in classical physics since classical physics is ontologically complete having no need of "consciousness" to support it. What Stapp does is to add "propensity events" (see below) into Bohm's interpretation of quantum physics, which complete the incomplete ontology of Bohm's quantum probabilities.

The "propensity" concept, put forward by Popper, Heisenberg, Wheeler, and others "is based on the idea that the actual things in nature are 'events' and that quantum theory specifies the 'objective tendencies' or 'propensities' for such events to occur," and these events form "records" (Stapp 1991:1452). These records are the connection between consciousness and brain process, because they are objectified collapses of wave functions, and occur on observation by human consciousness.

The concept of collapsed wave function as being the key to quantum physical and mental overlap seems to be very consistent in the literature. Many authors accept it as assumed, and work only on trying to explain how the process works. Given that the brain is a "chaotic structure" because of its complexity (King 1991:305), it is thought that the wave function collapse best supports the sensitivity and indeterminacy of the system.

Popper and Eccles, for example, feel the wave collapse hypothesis best fits the idea of a classically deterministic "brain," while allowing for the possibility of free will and creativity (non-deterministic) for "mind." Earlier we discussed Eccles's and Beck's theory of atomic switches ("triggers") stimulating release of synaptic material. In their opinion, "mind" is the thing that stimulates the atomic switches, varying the probability gradients (a non-deterministic, thus non-classical function) to produce neural phenomenon (which then produces "deterministic" results), and vice-versa. Mind, therefore, has much more of field attributes to them, unlike the folk psychology (common, intuitive ideas which non-scientifically try to explain behavior) projections of a spiritual or a magical ephemeral entity "hovering over" our brains. Their position is essentially dualistic, formerly thought to be a dead-end for philosophy. With their concept of shiftable quantum probability gradients, dualism is once again capable of regaining momentum, since they postulate a non-physical mind which alters the physical brain.

Penrose is another author who delves into wave collapse-mind theorizing. His book The Emperor's New Mind (1989) has quickly become a paradigm for mind research from a physical perspective. He bases his opinion on the theory that gravity is the key that collapses the wave function. He has noted in Shadows of the Mind (1994), that Einsteinís theory of gravity has been one of the most difficult pieces to fit into the quantum puzzle, but once it is made to fit, it may be a huge step in explaining consciousness.

Most of the authors presented here, put forward, in weak or strong forms, the idea that the brain is a quantum computer. One of the benefits of this is the self-referential character we see in studying mind, which cannot be explained using classical physical philosophy.10 If one considers the brain/mind to be a formal system, it will not be able to examine itself. But if one considers the brain to be a quantum computer having shiftable probability gradients (via Eccles), the paradox of introspection might be circumvented, since the brain isnít introspecting the brain, but the (separate) mind is introspecting the brain, and vice-versa.

Conclusion

There are many gaps in our current understanding of neuroscience at a molecular as well as at an holistic level. There are also gaps in how we are able to apply quantum physics to many phenomena which currently appear to be based on classical physics but which may actually be based on quantum physics, including neurophysiology. Whenever gaps in science occur, wild, spiritual philosophizing occurs. Not that this kind of thinking is necessarily unproductive and wrong--sometimes it leads to provocative and helpful paths. But it can also lead away from answers that could be found using natural science, such as believing the Bible says God created the universe and human-kind in seven days, while refusing to examine any scientific evidence. I am not saying, however, that non-scientific "myths" about reality are less true than the explanations given by contemporary science, since, realistically speaking, science is only a "myth" in itself, accepted by our Western culture.

Understanding the limits of science is important in any kind of philosophizing. For instance, science cannot determine ultimate causes, nor can it determine "ought" from "is" (for example, claiming that humans should live in a competative relationship with nature and with each other, because that is the nature of carnivores). My point is that we are in difficult territory. Some people claim to answer all questions using science alone, believing that all other efforts are futile. Others (including some scientists) throw their hands in the air and fall back on faith propositions to explain everything. As with most ventures in life, balance, patience, and caution is warranted.

Currently quantum physics appears to many to be the panacea for the mind-brain problem. But there are gaps, and as with all science in the past, new discoveries will probably lead us into totally new directions. So as this newest and growing field of neuroscience develops, many questions will be raised about the ethics and philosophy of mind. As these questions are investigated, we will need data from many fields, including quantum physics, as well as the maturity to accept the fact that some questions we may never be able to answer within the paradigm of science.


Footnotes

1. This paper contained a Gedanken experiment which had two photons emitted from a source going in opposite directions which experienced bizarre behavior. This thought experiment was originally designed to show the inadequacy of quantum theory because of the bizarre behavior predicted by quantum theory. But when a similar experiment was actually done by Alain Aspect (I review this experiment shortly), the thought experiment proved (surpisingly) correct, thus substantiating quantum theory instead of refuting it.

2. Definitions are in order at this point. To "reduce" a "quantum state" means to make it a phenomenological reality, whereas prior to reduction it is merely a "superposition of probability distributions." A quantum state is a theoretical concept that gives us an image of what might be going on with the particle/wave in question. It represents the compilation or "superposition" of various possible directions the particle/wave might go, or how it might otherwise be interacting with its environment. The reason it is called a superposition, is that, mathematically, when we look at a quantum state, we are looking at various individual choices that "could" happen, and we see all of the possible choices coexisting "at the same time" in the same equation, somehow in a very real, physical sense! For example, if we took a particle and gave it two possible paths it could take, in classical physics it could only take one path. But in quantum physics, the one particle somehow takes both paths, and only at the end does the particle actually "appear" (become "reduced"). This is not an unreal theoretical construct, because the effects of the particle can actually be found in both paths, even though it is only "reduced" in one path. This is what makes quantum physics so counter-intuitive and shocking to our classical physics mentality.

3. This hypothesis has been experimentally verified. See Ruhnau (1991) and Aspect (1982) for descriptions of these experiments

4.A transducer is a device which changes one thing into another. For example, a solar cell transduces light into electricity, and an engine transduces gasoline into the power in the pistons, which is then further transduced by the transmission into turning wheels.

5. One might wonder at this point about the nature of "minds" of other spiritual beings, such as angels, and God, who presumably do not have "brains" as this paper defines brains. As I will address later, a mind could conceivably be produced by any complex information processing system, not just a biological-neuronal system. Angels could have been imputed with such a system, allowing them to have minds. God, however, is another question, but one which I donít know that we could address, since I would assume that He is qualitatively different enough from humans that we can draw no conclusions about the ontology and/or origin of Godís mind.

6. Tunneling is the phenomenon we see when a particle/wave breaks through an energy barrier. For a macroscopic analogy, consider a billiard ball thrown against a wall (the energy barrier). In classical physics, the ball will hit the wall, and bounce off. In quantum physics, there is a possibility for the ball to pass through the wall, or tunnel through the wall. This phenomenon is so common and predictable, it is used in many technologies today (for example transistors and a special kind of microscope).

7. Several studies support this hypothesis. The reader is referred to Beck (1992), King (1991), Liu (1992) and Wallich (1993).

8. Superconductivity is a phenomenon in which there is little or no resistance to the passage of electrical current through a wire. This is a result of all of the particles of the wire acting in a cohesive, unified way such that they offer no resistance to the ions passing through it. The amazing thing about this phenomenon, is that somehow, the billions of individual particles act together, as if orchestrated by a "mind." This result is usually only obtained when the wires are brought to an incredibly low temperature, but recently there have been large temperature thresholds at which superconductivity occurs. It is thought that materials will soon be found that could super-cond/uct at room temperature, thus providing an analogy for brain function.

9. Current opinion about the place of quantum physics in the larger picture is that it is only a "special case" of classical physics. Bohm believes quantum physics is actually the foundation and classical physics is merely the special case of mass action of quantum phenomenon

10. Hofstedter deals with this issue of self-referentiality in Goedel, Escher, Bach (1979). Self-referentiality is an idea linked to Goedelís Incompleteness Theorem. One reason why his theorem is so powerful is that it shows that all previous attempts to "prove" the validity of math referred back to themselves in the proofs, thus making the proofs invalid (circular logic). Self-referentiality produces paradox because it causes a system, in essence, to "step outside of itself" to "refer back to itself," which, physically speaking, is impossible. For example, the statement "This sentence is false," is a paradox if taken literally. If it is true, then it is false, and if it is false, then it is true! This sentence is an example of the kinds of concepts encountered with systems that refer back to themselves.