Rationalist Spirituality

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by Bernardo Kastrup


  Chapter 5

  The brain as a consciousness transceiver

  There is a clear relationship between consciousness and the brain. Scientific analysis has shown significant correlation between objects in consciousness and specific neural activation patterns in the brain.1 We also know that electromagnetic stimulation of specific regions of the brain leads to alteration of subjective experiences.2 In addition, from direct personal experience, many of us are familiar with the effects that alcohol and other drugs can have in our states of consciousness through affecting the chemistry of the brain. Finally, we all know that sufficient damage to the brain, or the use of anesthetics,3 consistently leads to an apparent loss of consciousness (or at least to the loss of a memory of consciousness). Therefore, we can safely infer that a functioning physical brain is a necessary condition for the manifestation of our regular conscious states. The question of whether or not it is a sufficient condition is another matter.

  From that perspective, one of the problems with Wigner’s interpretation of quantum mechanics is this: if our regular consciousness causes collapse of the wave function, thereby manifesting physical reality, then who or what caused the reality of the physical brain, a necessary condition for the manifestation of regular consciousness in the first place? After all, the physical brain, as any physical structure, must obey the same laws as the rest of physical reality. Its wave function must be collapsed for it to exist in the material world. Thus we have an apparent chicken-and-egg situation that we need to resolve.

  To motivate Wigner’s interpretation of quantum mechanics, we stated that wave function collapse needed a causal agency from outside known material reality. Then, we postulated consciousness as a natural candidate for that. This implies that consciousness somehow “emanates” from as-of-yet undetected aspects of reality, which are not entirely governed by the known laws of quantum mechanics. This would indeed be contradictory with the orthodox materialistic position that a physical brain generates consciousness, but not with the postulate that a physical brain is necessary simply for the manifestation of consciousness in material reality. More specifically: a physical brain is a necessary condition for the interaction of consciousness with the known, material aspects of reality; consciousness itself being a natural property that emanates from as-of-yet unknown, non-material aspects of reality.

  The line of argumentation above may suggest some form of substance dualism, that is, the idea that consciousness and brain are made of different “stuff”. Substance dualism has been at the basis of most Western religions, being represented in the conception of a spiritual world separate from the material world. My view is that substance dualism is just a way to categorize reality between understood aspects, detectable and describable with our current scientific means, and not-understood, yet undetected aspects. For that matter, this boundary between understood and not-understood aspects of reality moves over time, reflecting the evolution of our knowledge: not so long ago, radio waves would have been classified as a not-understood, somewhat “supernatural” aspect of reality. From this perspective, substance dualism represents merely a so-called “epistemic” classification, that is, a way to organize and label our knowledge of reality, but not a claim that reality itself is somehow intrinsically divided into fundamentally separate realms. Seen this way, substance dualism is not inconsistent with so-called ontological monism, that is, the idea that there is but one, indivisible reality amenable to investigation. To the extent that substance dualism is interpreted as a handy epistemic classification, it is consistent with the line of argumentation above. However, it has not been my intention to imply that reality is somehow fundamentally split between a realm that is knowable and another that is unknowable in principle.

  Discussions about dualism and monism aside, in order to continue our analysis we clearly need a framework to think about how consciousness interacts with the known, material aspects of reality. We have concluded earlier that a physical brain is a necessary condition for this. We have also concluded that consciousness emanates from aspects of reality that are yet unknown to science. A natural model that captures both of these observations is that of the physical brain as a “transceiver” of consciousness in the material world, that is, a kind of “telephone”. The word “transceiver” is an amalgamation of “transmitter” and “receiver”, suggesting a kind of two-way communication between the aspects of reality where consciousness is grounded and the material aspects of reality governed by the laws of quantum mechanics.

  To gain some intuition about the logic of this model, consider robotic interplanetary exploration vehicles like NASA’s Mars rovers “Spirit” and “Opportunity”.4 The rovers were launched in 2003 and spent years exploring the surface of Mars with cameras and other scientific instruments. Despite being controlled remotely from Earth, the robotic vehicles had a certain degree of autonomy embodied in their on-board navigation, data processing, and housekeeping algorithms. Beyond that, they operated as transceiver platforms for the humans on Earth. All images mission control could see of Mars were captured and transmitted by the robotic vehicles. All activities that mission control wanted to carry out on Mars, like drilling on rocks, taking pictures, or moving around, were executed through the robotic vehicles after receiving commands from Earth. In a sense, the members of mission control were very much present on Mars, interacting with the Martian environment through a number of sensors and actuators. Not only was information collected, but concrete changes were left on Mars as a result of their presence there, like tracks on soil or holes in rocks. However, their presence on Mars was a virtual one, operating through the transceiver platforms constituted by the robotic vehicles.

  By now, as a critical reader, you will have already understood where I am going with this and will be asking yourself: “Why would nature impose on itself such limitations as the ones faced by interplanetary explorers operating robotic vehicles?” It apparently makes no sense and sounds utterly forced and artificial. Nonetheless, I have come to conclude that it is the answer to this very question that lies at the heart of the meaning of existence and, as a consequence, the meaning of life. But let us not rush. We will address this question head-on in the coming chapters. For now, I ask for your patience and an open mind. All we are trying to accomplish in this chapter is to postulate the simplest possible model for the interaction of consciousness with the known material world that simultaneously satisfies the two conditions identified earlier: first, that consciousness emanates from outside the domain of quantum mechanics; and second, that the physical brain is a necessary condition for the manifestation of consciousness in material reality. The first condition is motivated by Wigner’s interpretation of quantum mechanics, while the second condition is motivated by empirical observations of the relationship between brain functioning and states of consciousness.

  Continuing on with our analogy, mission control on Earth was limited in their ability to receive information from Mars, as well as to send commands to Mars, by the capabilities of the robotic vehicles physically on Mars. They could not carry out any activity on Mars that was not supported by the on-board instruments and actuators on the robots. They also could not receive any information from Mars whose acquisition was not supported by the capabilities of the on-board sensors and information processing devices of the robots. Another main limitation was the communication bandwidth between mission control on Earth and the robotic vehicles on Mars. In other words, the amount of information per second that could be transmitted back and forth between Earth and Mars limited what could be accomplished. A way around bandwidth limitations was to perform as much data processing in the robots themselves as possible. It was much more efficient to transmit “pre-digested” data from Mars to Earth, in the form of experimental results or compressed images for instance, than raw data. Indeed, raw data tends to require orders of magnitude more communication bandwidth than processed data. Therefore, the robotic vehicles carried out as much data analysis as possible locally, o
n Mars, before transmitting “pre-digested” results back to earth. The same holds the other way around: the more autonomy the on-board robotic systems had in terms of taking their own decisions about routes to take or things to do, the less “raw” commands needed to be sent out from Earth. Ideally, only exploration objectives would be sent out from Earth; the robots themselves determining how to go about achieving those pre-set objectives. For instance, it would be much more efficient to send a command in the form of “find your way to point A”, instead of “drive one meter forward; then stop; then turn 45 degrees; then drive another five meters forward; then stop”, etc. Naturally, the former alternative would require a higher degree of autonomy and, dare I say, intelligence on-board the robotic transceiver platform. We will discuss more about the role of intelligence with respect to consciousness in a later chapter. For now, bear with me a little longer.

  It is conceivable that advanced robotic explorers in the future will go beyond “pre-digesting” data and use their artificial intelligence systems to already compute entire sets of data interpretations and conclusions locally, thereafter sending to Earth only those conclusions. Mission control on Earth would, then, never get access to the original data collected, but only to the interpretation of that data developed by the robots themselves. Mission control’s understanding of another planet would, in this case, be restricted to the robot’s own ability to model and interpret the data it collects from that planet.

  Our physical brain is an amazing information processing platform. It receives information from our five senses, processes and analyzes it, and issues commands to our physical body. In the framework of orthodox science, this is in every way analogous to advanced interplanetary robotic explorers except one: orthodox science postulates that the brain is the final arbiter. Here, instead, we are postulating that the brain is a platform for acquiring data, processing it, analyzing it, “transmitting” the results of this analysis to consciousness, “receiving” causal influences from consciousness, further processing these causal influences, and finally issuing resulting commands to the physical body. If this sounds too far-fetched to you, bear with me a little longer, for soon we will look at specific, physiological mechanisms in the brain that could support this. There are very reputable scientists out there who take this idea very seriously.

  Most scientists feel comfortable with the idea of the brain crunching data before “presenting” it to consciousness; after all, this is pretty much consistent with all scientific data we have on perception. However, most are not comfortable with the idea that the brain also “receives” causal influences from an immaterial consciousness emanating from yet-unknown aspects of reality. The latter would be an instance of what is called “downward causation” in philosophy.

  Philosophically speaking, if immaterial consciousness could not make choices that influence our thoughts and actions in the world, our conscious selves would be mere spectators of the dance of existence. We would not be able to change the course of things in any way, and free will would be merely an illusion. All of our thoughts and actions would be fully determined by the electrochemical processes of our brain physiology. The consciousness that emanates from yet unknown aspects of reality would be limited to observing but not influencing anything through choice. We would just think we are making decisions, but that in itself would be an artifact of our brain physiology and the way its operation is presented to consciousness.

  Such a picture of reality could still be compatible with there being meaning to existence. After all, there would still be an audience to watch the stage play and confer on it its material existence through wave function collapse, even though the audience could not make choices about the turn of events in the play. There would still be subjective experience giving meaning to the universe, though that experience would not be able to causally affect the universe’s dynamics. The bottom line is: we cannot discard this view as inconsistent with our starting hypotheses.

  However, empirical observations tilt the balance in favor of downward causation. Indeed, important indications that consciousness causally influences brain function come from neuroscience experiments. Experiments have been performed in which subjects were asked to direct their conscious attention in particular ways, driven by their own willpower. Brain scan analysis of the effects of such conscious efforts revealed that they could physically alter neural circuitry and brain function in general, even in cases of brain pathology. This effect has been called “self-directed neuroplasticity”, and is an accepted phenomenon.5 It suggests that consciousness, and choice as an object in consciousness, is separate from, and can causally affect, brain functioning. Otherwise, how could something that is merely a result of brain activity choose to, and actually cause, a change in the very brain that generates it in the first place? That would be analogous to saying, for instance, that images of slides projected onto a screen could somehow choose and affect the inner-workings of the projector that generates them in the first place.

  The more technically astute reader may argue that, if there were a built-in feedback mechanism in the brain whereby neural correlates of conscious states could physically influence neuro-physiology, then self-directed neuroplasticity could be explained without contradiction with the hypothesis that consciousness is purely the result of brain activity. In our analogy, this would be like saying that the projector has a built-in digital camera focused on the images projected on the wall, and that the signals captured by the camera are wired directly into the inner mechanisms of the projector, thereby causally influencing its functionality.

  Strictly speaking, there is nothing illogical or inconceivable with this possibility, though it would require a surprisingly complex and global feedback mechanism in the brain that neuroscientists today could not begin to explain. Indeed, in some of the experiments performed, the subjects were instructed to use their willpower to alter the very emotional reaction that would be normally expected. For instance, when shown a photograph that would normally enact sexual arousal, subjects were instructed to use conscious effort to modify this instinctive, hardwired emotional response. Surprisingly enough, such efforts were often met with successful results. If conscious states were entirely the result of deterministic electrochemistry in the brain, the state of sexual arousal should be a deterministic outcome, yet that does not appear to be the case. As Jeffrey Schwartz, of the UCLA Neuropsychiatric Institute, put it, “When, as happens in a growing number of studies, the subject makes an active response aimed at systematically altering the nature of the emotional reaction […] then the demand that the data be understood solely from the perspective of brain-based causal mechanisms is a severe and counter-intuitive constraint.”6

  This strongly suggests, though it does not prove, that consciousness is not simply a result of brain activity, but somehow is able to exert causal influences on the brain from “outside” or “above” the brain. Such downward causation performed by consciousness on brain structure and function, in turn, may influence what other subjective objects later appear in consciousness.

  The orthodox position that consciousness is merely a result of brain activity rests, in a way, on the assumption that brain activity is deterministic. In other words, it assumes that the brain’s structure and perceptual inputs fully determine conscious experience. However, if the outcomes of neural processing fundamentally depend on quantum mechanical principles, we have seen that brain activity then cannot be deterministic: it will depend on wave function collapse that is caused, according to Wigner’s interpretation, by immaterial consciousness. The question now is: do we have reasons to believe that neural processing should be understood on the basis of quantum mechanics? It turns out that we do. And that offers even more evidence that, indeed, consciousness is not merely the result of brain function, but instead emanates from “outside” the brain, causally influencing its functioning.

  World-renowned mathematician and physicist Roger Penrose,7 anesthesiologist Stuart Hameroff,8 and physicist Henry
Stapp,9 amongst others, have elaborated upon specific aspects of brain function that seem to be quantum mechanical in nature. In doing so, they have proposed different mechanisms for how immaterial consciousness could interact with the physical brain. These proposed mechanisms could satisfactorily explain self-directed neuroplasticity. Notice that the articulation of this book is agnostic of which particular mechanism of brain-consciousness interaction holds true, so long as we can reasonably infer that there is one such a mechanism consistent with the transceiver model described earlier. Henry Stapp’s proposed mechanism is a particularly elegant and eloquent example, so I will describe it in a little more detail below to help you gain some intuition about how all this could work in the brain.

  We know that the brain is composed of networks of interconnected, specialized information-processing cells called neurons. Neurons in the networks are connected to each other through nerve terminals, which can transmit signals across neurons. All brain function rests, at its basis, on signals communicated between neurons through these nerve terminals. Each time a neuron tries to communicate with another, this communication attempt is mediated by the movement of calcium ions inside the nerve terminals. Therefore, brain function dependents fundamentally on whether or not the movement of these calcium ions triggers each attempted neural communication. Now here is the key: Stapp states that the movement of the calcium ions, given the dimensions and conditions involved, must happen in accordance with quantum mechanical laws. Consequently, whether or not the calcium ions trigger a communication between neurons is the result of wave function collapse, itself caused by a consciousness emanating from non-material aspects of reality. According to Stapp, this is how immaterial consciousness interacts with the physical brain. Notice that, with this mechanism, there is no discrete “antenna” or localized region of the brain where the interaction with emanating consciousness exclusively takes place. Instead, many of the gazillions of nerve terminals distributed throughout the brain respond to the causal influences of immaterial consciousness. Without consciousness causing wave function collapse at the nerve terminals, all brain processing would “grind to a halt”, so to speak.

 

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