QUANTUM MECHANICS : THEORIES OF CONSCIOUSNESS (Part2)

QUANTUM MECHANICS : THEORIES OF CONSCIOUSNESS 

(Part2)

Quantum Agents

This problem of the indeterminateness of the conscious choices is resolved in orthodox Copenhagen quantum mechanics by adopting a pragmatic stance. The theory is considered to be a set of rules useful to a community of communicating, conscious, observing agents imbedded in a physical universe. These agents make conscious decisions about how to probe that universe, in order to observe responses that will augment their knowledge. The difficulty mentioned above, which is that the known laws do not determine which of the possible probing questions will be physically posed, is neatly resolved by saying that this very openness allows the conscious agents to freely choose which probing questions they will physically pose. Thus the causal gap in the mathematically described structure is filled by the free choices made by conscious agents.

Bohr often emphasized the freedom of these agents to make these choices:

The freedom of experimentation, presupposed in classical physics, is of course retained and corresponds to the free choice of experimental arrangement for which the mathematical structure of the quantum mechanical formalism offers the appropriate latitude. (Bohr, 1958, p.73).

To my mind there is no other alternative than to admit in this field of experience, we are dealing with individual phenomena and that our possibilities of handling the measuring instruments allow us to make a choice between the different complementary types of phenomena that we want to study. (Bohr, 1958, p. 51). 

These quotes highlight the key fact that selection of the Process 1 probing events is determined, within the framework of contemporary physics, not by known mathematical or physical laws but rather by free choices made by conscious agents.

Von Neumann’s Move

John von Neumann formulated Copenhagen quantum mechanics in a mathematically rigorous form, and then, in order to remove ambiguities associated with the placement of the Heisenberg cut, showed that this cut could be pushed all the way up, so that the entire physically describable universe, including the bodies and brains of the agents, are described quantum mechanically. This placement of the cut does not eliminate the need for Process 1. It merely places the physical aspect of the Process 1 psychophysical event in the brain of the conscious agent, while placing the conscious choice of which probing question to pose in his stream of consciousness. That is, the conscious act of choosing the probing question is represented as a psychologically described event in the agent’s mind, which is called by von Neumann (1955, p. 421) the “abstract ego”. This choice is physically and functionally implemented by a Process 1 action in his brain. The psychologically described and physically described actions are the two aspects of a single psychophysical event, whose physically described aspect intervenes in the orderly Process 2 evolution in a mathematically well defined way.

Bohr emphasized that the laws of quantum theory should continue to be valid in biological systems, but that the latitude introduced by the severe constraints upon observation imposed by the demands of sustaining life could permit such concepts such as “teleology” and “volition” to come consistently into play. (Bohr, 1958, p.10, p.22)  

Interactive dualism

Orthodox quantum theory is a theory of a type called interactive dualism, which goes back in modern philosophy to Descartes, and before that to the ancient Greeks. An interactive dualism postulates the existence of two entirely different kinds of realities, mental and physical, that interact. Mental realities have the character of feelings, broadly construed to include thoughts, ideas, perceptions, pains, joys, sorrows and all things that enter directly into our streams of conscious experiences, and are described basically in psychological language. Physical realities are elements that are described in our theories of nature in terms of mathematical qualities assigned to space-time points.

 Interactive dualism combined with the precepts of classical physics gives classical interactive dualism. This has been attacked ferociously by philosophers for over three hundred years, with an intensity that has been increasing over the past half century.  Quantum interactive dualism is based, instead, on orthodox (von Neumann) quantum theory.

The first main objection to classical interactive dualism is that it postulates the existence of two entirely different kinds of things, but provides no understanding of how they interact, or even can interact. The second main objection is that the physical description is, by itself, already causally complete, giving a completely deterministic account of the evolution in time of every physically described entity, which means that the mental realities have nothing to do, and no possibility of influencing anything physical. The mental side is a “ghost in the machine” that is imagined to be pulling the levers in order to ‘work its will’ in the physical world, but cannot really be doing so because the behavior of the physically described universe is completely determined independently of the ghostly machinations.

Quantum interactive dualism neatly evades both objections. The answer to the first is that the form of the interaction between the mentally and physically described aspects of nature is specified in von Neumann’s account of the measurement process. This account is part of a careful mathematical description of the fundamental principles of quantum theory, and of how they are to be employed in practice.   The specification of the form of the interaction between the two differently described aspects is an essential part of von Neumann’s formulation of quantum theory. It is essential because quantum theory is specifically designed to be a tool that allows physicists to make computations that connect their experiences about setting up probing experiments to their expectations about the observable responses to these probing actions. Such a theory requires an adequate theory of measurement and observation, which von Neumann provides.

As regards the second objection, a huge essential difference between the classical and quantum dualities is that in the quantum case the physically described part is not causally complete. Something else is needed to complete the dynamics. Mental realities function both to complete the causal structure and also to undergird what the theory is basically about, namely the structural relationships between the elements in our streams of conscious experiences.  

In my characterization of interactive dualism I spoke of two kinds of realities, physical and mental. Mental realities are certainly real: a presently felt pain really does exist. The experiencings of theoretical ideas in the streams of consciousness of physicists are also real happenings.  But the existence in nature of real entities that have all the properties ascribed by the precepts of classical physics to, say, “electrons” would be surely denied by most quantum physicists. Quantum philosophy recommends avoiding commitment to the idea that there are realities in nature that accurately conform to our theoretical ideas about the physical universe. In regard to the physical it is only the descriptions themselves, and the way that they are used, that are ascribed significance in orthodox quantum philosophy. Ontological commitments pertaining to the physical are not part of science. In general, the practical meanings of descriptions are defined in the end by how the descriptions are used in practice.

The fact that the form of the interaction between the psychologically and physically described aspects of quantum theory is specified is important: it severely constrains the theory. Arbitrary ad hoc proposals cannot be postulated willy nilly. For example, many proposals are ruled out by the fact the living brain is large, warm, and wet, and interacts strongly with its environment. The first, and very stringent, demand on any serious proposal is that it work in this hostile-to-quantum-effects setting.

The only pertinent quantum effect known to me that survives robustly under these hostile settings is the quantum Zeno effect, so-named because of its rough similarity to the paradox that claims that the hare can never catch the turtle because, by the time the hare reaches where the turtle was, the turtle will have moved on. That claim is obviously false. But there is a vaguely similar claim about quantum mechanics that is unquestionably true (Misra, 1977). If, under appropriate conditions, one repeatedly poses the same probing question at a sufficiently rapid rate, then the sequence of responses will tend to get stuck in place. In the limit of arbitrarily rapid re-posings, the response will become frozen: all the responses will come out to be the same, even though very strong physical forces may be working to make them change. Thus a manipulation of the timings of the probing actions, which are under the control of the consciousness of agent, can have, even in a warm, wet brain, a very special kind of physical effect. If, by mental effort, an agent can cause a sufficient increase in probing rate, then that agent can cause a state of intention and attention to be held in place much longer than would be the case if no such effort were being made.   

The crucial point, here, is that the physically-described laws of quantum mechanics do not fix the times at which the physical Process 1 probing actions occur, or what these physical probing actions will be. This lacuna is the essential reason why the conscious “free choices” on the part of human agents were brought into quantum mechanics by its founders, and were retained by John von Neumann! These conscious choices control the timings of the physical Process 1 events studied by Misra and Sudarshan, and this connection entails, in principle, the capacity of these psychologically described aspects of the streams of consciousness of agents to control, via quantum Zeno holding actions, certain physically described features of the world.

Huge survival benefits could accrue to agents that can exploit this feature of the quantum mechanics, because this intentional stabilizing of attention would hold in place also the corresponding pattern of functional brain activity.

Such a holding effect could, of course, be postulated, ad hoc, to occur in a classical-physics-based model. But in that case the holding effect would not be a direct consequence of the same basic psychophysical laws that are used by physicists to explain atomic phenomena. In the quantum case the holding effect is probably the only robust kind of effect of mind on brain that the theory predicts, whereas any desired regularity could postulated in a theory that simply adds mind ad hoc. As regards classical-physics-based theories, the view of physicists is that classical physics is an approximation to quantum physics. All effects of conscious thought upon brain activity that follow from quantum theory, such as the quantum Zeno holding effect, are eliminated in the classical physics approximation, because in that approximation the uncertainty-principle-based latitude within which the causal effects of mind upon the physically described aspects of nature operate shrinks to zero.

Comparison to psychological findings

The dynamical effect described above of a volition-induced high rapidity of the Process 1 probing actions is exactly in line with the description of the effects of volition described by William James (1892). In the section entitled Volitional effort is effort of attention he writes:

Thus we find that we reach the heart of our inquiry into volition
when we ask by what process is it that the thought of any
given action comes to prevail stably in the mind. (p. 417)
 The essential achievement of will, in short, when it is most
‘voluntary,’ is to attend to a difficult object and hold it fast
before the mind. (p.417). Everywhere, then, the function of effort is the same: to keep
affirming and adopting the thought which, if left to itself, would slip away.(p.421)

James may have foreseen, on the basis of his efforts to understand the mind-brain connection, the eventual downfall of classical mechanics. He closed his book with the prophetic words

…and never forget that the natural-science assumptions with which we started are provisional and revisable things. (p.433)

A lot has happened in psychology since the time of William James, but these newer developments support James’s idea of the holding-attention-in-place action of volition. Much of the recent empirical and theoretical work pertaining to attention is summarized in Harold Pashler’s book The Psychology of Attention (Pashler, 1998). Pashler concluded that the evidence indicates the existence of two distinct kinds of mental processes, one that appears not to involve volition, and that allows several perceptual processes to proceed in parallel without significant interference, and one that does involve volition and that includes planning and memory storage. This latter process seems to involve a linear queuing effect with limited total capacity.

These properties of volition-driven processes appear to be explainable in terms of the basic laws of orthodox quantum physics, which entail the existence of Process 1 physical events whose timings are controlled by conscious choices, and which can, in principle, by means of the quantum Zeno effect, tend to hold in place a pattern of neural activity that will tend to bring into being an intended effect. But this holding effect drops out in the classical-physics approximation, in which all physically described properties become completely determined by physically described properties alone, with consciousness a causally inert, or causally superfluous, bystander. Correlations between physically and psychologically described properties can be described within a classical physics based framework, but the psychologically described aspects will remain essentially epiphenomenal by-products of brain activity.

This evidence from psychology is discussed in detail in Stapp (1999, 2001) and in Schwartz, Stapp, and Beauregard (2003, 2005)

Application in Neuroscience

The most direct evidence pertaining to the effects of conscious choices upon brain processes comes from experiments in which identifiable consciously controllable cognitive processes seem to be controlling directly measured physical processes in the brain. An example is the experiment of Ochsner et.al. (2001). The subjects are trained how to cognitively re-evaluate emotional scenes by consciously creating and holding in place an alternative fictional story of what is really happening in connection with a scene they are viewing.

The trial began with a 4 sec presentation of a negative or neutral photo, during which participants were instructed simply to view the stimulus on the screen. This interval was intended to provide time for participants to apprehend complex scenes and allow an emotional response to be generated that participants would then be asked to regulate. The word Attend (for negative or neutral photos) or Reappraise (negative photos only) then appeared beneath the photo and the participants followed this instruction for 4 sec …

To verify whether the participants had, in fact, reappraised in this manner, during the post-scan rating session participants were asked to indicate for each photo whether they had reinterpreted the photo (as instructed) or had used some other type of reappraisal strategy. Compliance was high: On less than 4% of trials with highly negative photos did participants report using another type of strategy.

Reports such as these can be taken as evidence that the streams of conscious of the participants do exist and contain elements identifiable as efforts to reappraise.

Patterns of brain activity accompanying reappraisal were assessed by using functional magnetic imaging resonance (fMRI). The fMRI results were that reappraisal was positively correlated with increased activity in the left lateral prefrontal cortex and the dorsal medial prefrontal cortex  (regions thought to be connected to cognitive control) and decreased activity in the (emotion-related) amygdala and medial orbito-frontal cortex.

How can we understand and explain the psychophysical correlations exhibited in this experiment?

According to the quantum model, the conscious feelings cause the changes in brain activity to occur. This causation is in strict conformity to the known laws of physics, as spelled out in von Neumann’s book Mathematical Foundations of Quantum Mechanics.

This causal explanation, this whole causal story, falls apart if one tries to explain this psychophysical correlation within the framework of the classical approximation. That approximation entirely eliminates the effects of our conscious choices and efforts upon the physical world, including our brains. But what is the rational motivation for insisting on using this approximation? The applicability of the classical approximation to this phenomenon certainly does not follow from physics considerations: calculations based on the known properties of nerve terminals indicate that quantum theory must in principle be used. Nor does it follow from the fact that classical physics works reasonable well in neuroanatomy or neurophysiology: Quantum theory explains why the classical approximation works well in those domains. Nor does it follow rationally from the massive analyses and conflicting arguments put forth by philosophers of mind. In view of the turmoil that has engulfed philosophy during the three centuries since Newton cut the bond between mind and matter, the re-bonding achieved by physicists during the first half of the twentieth century must be seen as an enormous development: a lifting of the veil. Ignoring this huge and enormously pertinent development in basic science, and proclaiming the validity of materialism on the basis of inapplicable-in-this-context nineteenth century science is not a rational judgment.

Of course, one can simply abandon the idea that ideas can actually cause anything physical, and view the feeling of effort as not a cause, but rather an effect, of a prefrontal excitation that causes the suppression of the limbic response, and that is caused entirely by other purely physical activities.

Viewed from a sufficiently narrow perspective that might seem to be a satisfactory conclusion, but it leads to the old problem: why is consciousness present at all, and why does it feel so causally efficacious, if it has no causal efficacy at all?  Why this big hoax? Quantum theory answers: There is no a hoax! It was only the premature acceptance a basically false physical theory, fundamentally inapplicable to the brain, that ever made it seem so!

 The only objections I know to applying the basic principles of physics to brain dynamics are, first, the forcefully expressed opinions of some non-physicists that the classical approximation provides an entirely adequate foundation for understanding brain dynamics, in spite of the quantum calculations that indicate the opposite; and, second, the opinions of some physicists that the hugely successful orthodox quantum theory, which is intrinsically dualistic, should, for philosophical reasons, be replaced by some theory that re-converts human consciousness into a causally inert witness to the mindless dance of atoms.  Neither of these opinions has any secure scientific basis.

There are several other quantum theories of consciousness, but all of them are based on von Neumann’s work. The physics considerations described above rest completely on that work. I shall describe next some proposals that go far beyond von Neumann’s secure base, and introduce some very controversial ideas.  

 QUANTUM MECHANICS : THEORIES OF CONSCIOUSNESS  (Part1)