by Eric Wargo
Memory is made possible by the brain’s plasticity, its ability to change from day to day, minute to minute, even moment to moment. The strengths of those trillions of synaptic connections are continually being updated based on our experience. Although different types of learning have been identified in different brain circuits, the most basic principle operative throughout the brain is what is known as Hebbian learning , captured by the phrase “neurons that fire together, wire together.” When a neuron sends a chemical signal to another neuron, the synapse where they link up is strengthened, so that future signals at that synapse will be easier—called long-term potentiation . Through this process, our experiences are self-reinforcing, like a trickle of water wearing a deeper and deeper rivulet in the soil to become a stream. By the same token, connections that are not reinforced decay or weaken over time—called long-term depression .
If there is a brain-based theory of precognition forthcoming in science’s future, it will likely involve these same processes of memory and learning, specifically the ability of synapses to update their facility of signaling. Lo and behold, the cytoskeleton of neurons—including the aforementioned microtubules—controls this process. 46
When the axon of an “upstream” neuron sends neurotransmitters to the dendritic spine of a “downstream” neuron, that dendritic spine enlarges and in other ways makes itself more receptive to future signals, as well as sending retrograde messengers to the upstream neuron that initiate similar changes in the axon terminal. These structural changes that enhance the ability to send and receive signals at a synapse are controlled by the shape-changing of microtubules—a process governed by a kind of chemical dance of proteins that continually disassemble and reassemble these structures, shortening and lengthening them at either end. 47 (Among the microtubule-associated proteins governing this shape-changing is tau; dysregulation of tau proteins is associated with the devastating impairments in Alzheimer’s disease.) Microtubules also transmit electrical signals through the cell and serve as tracks for the transport of cellular raw materials. In reshaping the synapse and controlling synaptic efficiency, microtubules act in concert with other cytoskeletal structures called actin filaments , which are also currently being studied as biological computational devices. 48
So, one hypothesis would be that these structures of the neuronal cytoskeleton may be behaving like tiny molecular versions of the apparatus in the Rochester experiment described in the last chapter: devices that somehow “weakly measure” the behavior of entangled qubits within them at time point A and then, after some regular, predictable length of time (probably rhythmically), perform a subsequent measurement—post-selection in other words. Post-selection might even be a function of the ever-shifting length of a microtubule, as its ends disassemble and reassemble. Via arrays of microtubular time eyes controlling the shape of axon terminals and dendrites, signaling at synapses may be potentiated or enhanced if they are going to be signaling in the future (and vice versa if they won’t be).
Remember that, according to the Dunnean view, precognition would not be a preview of future events out in the world, as is often assumed (negatively assumed, for those who reject precognition on principle); it is instead a presponsivity of the brain to its own future states and behavior (thoughts, emotions, perceptions). If quantum computation in the cytoskeleton enables synaptic connections to be conditioned by their future signaling, this would scale up in complex networks of interlinked neurons, enabling whole “pre-presentations” of thoughts and emotions to be projected into the past, albeit imperfectly and imprecisely, in roughly the same way that salient experiences “project” into the future as memories. There is no question in this model of the brain somehow “receiving” information directly from future events; it is simply communicating with itself across time. 49
This is by no means the first brain-based model for precognition to be proposed. I already mentioned Gerald Feinberg, who suggested in the mid-1970s that precognition is just memory in reverse. Speculating on a possible mechanism, he proposed that brain oscillatory patterns thought to play a role in short-term memory might have both an “advanced” and “retarded” component to them, in the manner of time-symmetric quantum-mechanical models. 50 More recently, Jon Taylor has suggested that similar patterns of neural activation at different points in time may resonate with each other across the brain’s timeline. 51 His proposal resembles Rupert Sheldrake’s argument that memory may be a function of informational patterns resonating across spacetime. But again, formative causation arguments (like Platonic models more generally) seem to put the cart of meaning (as “form”) before the horse of causation. Current retrocausal paradigms in quantum physics offer an interesting alternative way of thinking about informational reflux from the Not Yet, since they apply the same principle to information that Darwin, Wallace, and their contemporaries did for natural forms: selection . Post-selection is really just causal Darwinism.
At its most basic level, a “signal sent back from the future” via post-selection would be one that necessarily indicates a course of action that survived long enough to send that message back—like a little breadcrumb trail from the organism’s future self, or a note at a crossroads weirdly in its own handwriting, saying “come this way.” Part of what post-selection entails is predictability, and thus the recognizability of that handwriting. The more the mechanism can anticipate its state in a few milliseconds or seconds or longer, the more information from its future can have coherence and context, making it meaningful or useful in guiding behavior. Here, in the organism’s relationship to itself across time, is where a kind of “resonance” may come into play, although it must be understood metaphorically. When scaled up in a complex animal nervous system like that of a human being, it may be something like habit or conditioning—a kind of self-trust that the state of the individual performing a measurement now will be more or less the same as the state of individual in a millisecond, a second, or a minute (or a decade)—that acts as a kind of post-selection, providing the cipher key of back-flowing information, enabling it to usefully guide behavior (i.e., be meaningful) rather than noise. 52
Other possibilities should also be kept on the table. For example, could there even be neurons in the body that fire in advance of incoming signals, kind of like Asimov’s thiotimoline molecule? 53 If a single neuron could get even a one-millisecond head start on firing, a chain of hundreds of such neurons (like a chain of Asimov’s endochronometers) could amplify that head start enough to explain the findings of Dean Radin, Daryl Bem, and other presentiment researchers. It is already known that quantum processes accelerate the transmission of electricity within neurons 54 , but for a downstream neuron to actually fire in advance of signals from the upstream neuron would seemingly require some kind of entanglement between molecules in separate neurons, across the synapse. Again, this kind of wider entanglement in the brain remains the holy grail for those trying to solve the problem of quantum consciousness, and it also remains the big stumbling block to those efforts, given the problem that entanglement tends to be lost in warm, wet environments. But researchers are rapidly learning about more and more ways quantum coherence can be sustained in biological systems over distances and across time spans that would have been thought impossible even a decade ago. 55 One puzzling phenomenon that is at least suggestive in this context is spontaneous neurotransmission —neurons firing without being triggered by any input from neighboring cells. Initially thought to be just “noise” in the brain (sound familiar?), it is now thought to play a role in reshaping synapses during learning. 56 Could it be evidence of thiotimoline-like neuronal behavior?
There is much we still don’t know, obviously. But the bottom line is that if synaptic plasticity or other aspects of neurons’ behavior or signaling are controlled or influenced by molecular computers capable of harnessing time-defying quantum principles, then it is likely here that an answer to “how can this be?”—that is, how can the brain get information about its future r
esponses to the world?—will be found. The biological basis of precognition would be learning processes in which the brain’s connectivity and signaling in the present are influenced not only by the individual’s past experience but also, to some as-yet-uncertain degree, by that individual’s future experience. It would enable that individual to “post-select” on rewards ahead and to be influenced by, if not intentionally access, information the individual will conventionally acquire down the road. 57
Such a proposal is, of course, still speculative, only slightly less hand-wavy than the various alternatives. It remains a hypothesis to be tested. But it does not fly in the face of what we are learning about quantum computational processes in biological systems and what some physicists are arguing (and discovering in the laboratory) about retrocausation. Thus, it should not be unpalatable even to materialists, at least in principle.
Libet’s Golem
It sometimes happens in science that new discoveries are made based on old data that were misinterpreted at the time they were collected because existing theories made no place for them. New species are often discovered in old museum collections, for example, when specimens are found to have been misidentified or just ignored, awaiting some shift in taxonomic or evolutionary paradigms. It may be that direct evidence of the nervous system’s time-defying behavior has been staring researchers in the face for nearly four decades. Famous perplexities having to do with the synchronization of sensation, action, and decisions would make more sense in a nervous system capable of computing four-dimensionally across its timeline than in any purely Newtonian information processor.
Older readers will remember drive-in movies—often badly projected and frequently the picture and sound were a few frames out of sync. If the nervous system is a purely classical, mechanical information processor, our everyday experience ought to be a little bit like an out-of-sync drive-in movie … but it isn’t, and why it’s not is a bit of a mystery. If you step on a sharp tack with your bare foot, the pain signal takes roughly a half second to travel 1.5-2 meters between your foot and your brain and for you to become aware of it. Each nerve cell in a long chain has to receive a chemical signal, fire, release its own neurotransmitters, and so on. However, other signals, such as the sight of your foot hitting the floor, have a much shorter “flight time” since light travels much faster from your foot to your eye than that chemical-electric pain signal traveling up your whole body. But if you watch your right foot as you are walking, you feel the sensation of your big toe touch the floor at exactly the same time as you see it visually. Why?
Neuroscientist Benjamin Libet discovered this contradiction between sensory out-of-sync-ness and the subjective experience of our harmoniously orchestrated bodily movements and decisions in a series of landmark experiments in the late 1970s and 1980s. To explain how we don’t experience life like a drive-in movie, he argued that some process in the brain “antedates” our conscious experience relative to the stimulus so that multiple sensations can match up and be felt as synchronous—sort of like taking separate video and audio tracks in a video editing program and sliding one to the side so the visual component synchs up with the audio. But since, it was assumed, you can’t slide the slower of those components (e.g., the pain sensation) to the right in your timeline, synching things up meant sliding all the faster signals to the left or holding them in some sort of buffer while the slower ones caught up. Libet concluded that the coherence of our experience, the fact that it is all synchronized, reflects the remarkable fact that we are really living always about a half second in the past . 58
It gets even stranger, though, when you include our feeling of conscious will in this fictitious synchronization. In 1983, Libet conducted a now-famous experiment that compared the subjective timing of participants’ decisions to move a finger with their motor nerves’ preparation to fire. He found that neurons begin to build up a charge a fifth of a second (200 milliseconds) before the decision to move is consciously made. This discrepancy between what is called the nerve’s readiness potential and the subjective sense of conscious will flies in the face of our ordinary experience of deciding to act and then acting, the intuitive sense that our will causes our actions and is not merely a spectator. 59 For a certain faction in psychology and neuroscience, Libet’s work was the last nail in Descartes’ coffin, the final death blow to the idea that consciousness is something over and above (and prior to) the mechanical operating of the brain’s circuits. Psychologist Daniel Wegner, for instance, expanded on Libet’s research and built an interesting (and troubling) case that our subjective experience of being the masters in our own house is altogether an illusion. 60 Libet himself did not go so far; he felt his discovery did not eliminate conscious will but altered its essential character. Instead of exerting free will, he said, we exert a veto power over pre-initiated actions. V. S. Ramachandran has called this “free won’t.” 61 Our conscious will can intercede within that 200-millisecond window to say “no” to an impulsive action initiated by the brain.
Much research in psychology and cognitive science over the past few decades has identified two systems that guide our behavior in parallel: a fast, largely unconscious, emotional system (sometimes called “System 1”), and a slower, more deliberate, more reasoned system that ideally hovers over and says “no” (“System 2”). It makes sense from an adaptive standpoint that, when making quick responses to real threats—such as swerving to avoid an oncoming car or changing your foot position to avoid a tack—we wouldn’t want our slower deliberative conscious will to get in the way and delay a response that the unconscious mind and body can handle more efficiently and swiftly. Yet even in the absence of such an impediment, how does a large animal like a human manage to survive when sensory signals take a measurable fraction of a second to reach the brain, where they must then be processed and interpreted, before a set of responses can then be sent back down parallel nerve channels to make a motion? It ought to make us very clumsy and easily defeated by sudden threats and by smaller animals with simpler nervous systems. And just imagine if you were an elephant, or a swift 10-ton T-Rex whose sensory and motor signals needed to travel many times that distance.
An emerging paradigm in psychology and neuroscience emphasizes the brain’s role as a predictive processor , meeting these challenges by generating constant simulations or forecasts that are able to guide the body toward anticipated outcomes. 62 A baseball player is able to swing at a point in space where he perceives the ball will be, rather than base his actions on constantly updated, but necessarily slow, moment-to-moment input from his eyes. It happens outside of conscious awareness—and it goes along with many “superpowers” that neuroscientists have attributed to our fast, unconscious processing, in a largely unacknowledged debt to Sigmund Freud and his generation of Victorian psychiatrists who were perplexed at humans’ seeming supernormal abilities (more on which later). But another possibility is that some of what gets labeled unconscious or implicit processing may really be the time-defying possibilities that have been revealed in the experiments of Bem, Radin, and their colleagues. Physicist Fred Alan Wolf proposed in the late 1980s that John Cramer’s transactional interpretation of quantum mechanics could explain Libet’s findings and may also help explain consciousness. 63 Quantum-biologically mediated presentiment, in other words, could be the real reason, or part of the reason, why our lives don’t feel like a drive-in movie.
If the brain really is a quantum future detector—or perhaps, trillions of quantum future detectors networked classically—then effective motor action might be initiated partly from a position displaced slightly ahead in an organism’s timeline, when the success of the action is already confirmed. Such a model would offer another way of thinking about skillful performance in sports or martial arts, for example, not to mention intuition, creative insight, and inspiration. I like to think of this possibility as “Libet’s golem,” an ironic, science-fictional perversion of the lumbering clay robot of Jewish folklore. It is conceiva
ble that we are not after all mere automatons, spectators of our bodies, as Wegner argued, but could be pulling our meat puppets’ strings from a position offset from the “now” of sensation, or perhaps even from multiple temporal vantage points distributed across time. This would be especially the case when engaged in a skilled activity, and it might account for the dissociated feeling that accompanies states of peak engagement and creativity. Could temporally displaced action-initiation even account for the “mental replay” that often follows a successful high-stakes action? In other words, when we mentally relive a successful action in its immediate aftermath, might we in fact be initiating that action, from that action’s future?
It is in this respect that gaining greater understanding of what happens in quantum computers, including biological quantum computers and the role they play in the nervous system, really could provide an important missing piece of the consciousness puzzle. Rather than being simply tantamount to coherence or entanglement across spatially separate parts of the brain, consciousness could instead (or also) have something to do with cognition being distributed across time. With its trillions of classical connections (i.e., chemical signals) mediating the actions of many more trillions of molecular quantum computers, the brain might turn out to be an exquisitely tuned device extracting and synthesizing relevant information from across some indefinite time window and bringing it to bear on an immediate situation or problem. Although our awareness remains tied to a single synchronized (yet in fact, fictitious 64 ) instant of stimuli coordinated among our five senses, we might in fact be “thinking with” a wider swath of our future as well as past history. In which case, the brain really would be a kind of informational tesseract, a 4-D meaning-machine.