Neurophilosophy

According to Efstratios Manousakis, a professor of condensed matter physics at Florida State University in Tallahassee, the key to consciousness could be lie in the quantum effects that occur in the brain when one is viewing ambiguous figures like the spinning silhouette (or Rubin’s vase or the Necker Cube).

These optical illusions are ambiguous because at any one instant they can be perceived either in one way, or in the other, but not in both. The image is said to “flip” when our perception changes from one interpretation of the image to the other. In the case of the spinning silhouette, some find it more difficult than others to switch between the two percepts.

Manousakis bases his model of consciousness on the assumption that conscious awareness is generated anew each time one flips an ambiguous figure. He believes that the ability to flip the image is akin to quantum superposition, in which both possible interpretations co-exist simultaneously in a state that can be expressed as a quantum wave function. Each time the image is viewed, the wave function collapses and one or the other interpretations is perceived.

Exactly what happens in the brain during the image flip could therefore be a neural correlate of consciousness, and may provide important clues to how the brain generates this most elusive of phenomena.

Manousakis therefore collated the data from studies in which participants had their brain activity measured with electroencephalongram and brain imaging while viewing ambiguous figures, and determined the firing rates of neurons before, during, and after they flipped the images. Using these figures, he then determined a firing pattern which he believes is characteristic of the quantum effects that underly consciousness.

Unlike some theories of quantum consciousness, such as that of Stuart Hameroff and Roger Penrose, this one is testable. Using data from studies in which participants were under the influence of LSD (which reduces the neuronal firing rate), Manousakis accurately predicted the frequency with which the subjects could flip the images.

Some researchers who have been critical of previous attempts to use quantum physics to explain consciousness therefore think Manousakis’s model is plausible.

Reference:

Manousakis, E. (2007). Quantum theory, consciousness and temporal perception: Binocular rivalry. doi: 0709.4516. [Full text

Comments

  1. #1 Anon
    October 23, 2007

    He can measure quantum effects with an electroencephalogram?

    Silly particle physicists, doing it all the hard way.

  2. #2 blah
    October 23, 2007

    *yawn*

    another attempt to explain consciousness by combining two things that are poorly understood in general but especially poorly understood by the one proposing the “solution”

  3. #3 carolyn13
    October 23, 2007

    The links you’ve made this week are so compelling, following them has left me no time to comment. So consider this my “Gee whiz, that’s fascinating!” post of the week.

  4. #4 Kurt
    October 24, 2007

    Manousakis bases his model of consciousess on the assumption that conscious awareness is generated anew each time one flips an ambiguous figure. He believes that the ability to flip the image is akin a quantum superposition, in which both possible interpretations co-exist simultaneously in a state that can be expressed as a quantum wave function. Each time the image is viewed, the wave function collapses and one or the other interpretations is perceived.

    I have to say that this is one of the stupidest things I’ve heard in a while regarding consciousness. There seems to be a certain subset of physicists who are really hung up on the notion that quantum mechanics leads in some direct fashion to consciousness. I mean, I have no doubt that quantum mechanics comes into play indirectly, simply because quantum mechanics underlies all of the physics involved in phenomena operating at the scale of a brain. But really — do we need to invoke quantum mechanics directly to explain why reduced neuronal firing rates while under the influence of LSD might affect the rate at which subjects could flip the images in their minds? Come on, now.

  5. #5 David Harmon
    October 24, 2007

    Pfft. It’s been a while, but I have played with simulated neural networks a bit. Even the simple simulations I was dealing with were prone to give ambiguous output, which could be “tipped” by tiny stimuli, or just “noise”. Because the simulations were so simple, I could actually examine the phenomenon directly, and it was just a matter of “tipping points” cascading through the network. Hauling in quantum mechanics to explain that is just an argument from ignorance — he doesn’t understand the fundamentals, so “it must be magic^W quantum mechanics”.

  6. #6 Tatarize
    October 24, 2007

    I see no reason to say that this is quantum anything. The brain is pretty much a prediction machine. We simply happen to take a guess at the spinning figure and which ever way we think it might be spinning gets reinforced as a valid theory because it results in an accurate prediction.

    Certainly we aren’t accustomed to things able to be two seemingly contradictory things at the same time and as such aren’t accustomed to predicting that happening so the brain chooses one and either one is considered correct and so we see it turning. Hardly requires a quantum wave collapse. It just requires a well evolved brain constantly making predictions about everything in the world around it.

    If anything, I’d say that quantum state collapse is an example of the same thing. Rather than being a real thing and a real answer it’s just the way we understand things because superposition doesn’t make any sense to our brains just as the idea that the figure is turning counter-clockwise and clock-wise and the figure is both inverted and non-inverted. Both ambiguous figures and superposition are examples of things our brains are just bad at understanding.

    So yeah, you should be able to use the same formulas we use to make superposition make sense to our brains to make sense of other seemingly contradictory states with equal truth values… but not because there are quantum events at work. But rather because we use the same stuff to make sense of quantum events as well.

  7. #7 mrG
    October 24, 2007

    I wonder if this could also mean that Diane Deutch’s audio ‘tritone’ illusion is another example of this consciousness correlate to quantum superposition and collapse … which might then also imply that the cognitive process of tritone-substitutions common in jazz performance makes jazz a uniquely fundamental conscious-quantum-dynamic musical genre!

  8. #8 CRM-114
    October 24, 2007

    Actually, the spinning silhouette can be seen going the one way, or the other way, or being ambiguous, or being both — the superposition of the one and the other.

  9. #9 gerald spezio
    October 24, 2007

    Although I wouldn’t dare apply quantum effects to Professor Manousakis’s brain in Tallahassee where quantum effects have already been applied to football, I am skeptical of any academic, especially a physicist, who uses the word consciousness and quantum effects in the same sentence.

    In his next paper the upward bound professor will claim, predictably – a new paradigm emanating from quantum effects superpositioned on consciousness studies, architectural technique, spirituality, and literature.

    You will know then that it is all horseshit, as in Fred Allen Wolff, Stuart Hammerhead, & Frithof Capture-the-Money.

  10. #10 PJ
    October 24, 2007

    Further to David, studies have been done in animals on bistable motion percepts which have found that you can induce one or other of the percepts by stimulating cells sensitive to motion in one or other direction. This seems like a rather more likely mechanism.

    As everyone else has said, I can see no role for quantum magic here, I’m particularly intrigued that an EEG might be supposed to measure anything on the quantum level.

  11. #11 Matthew L.
    October 25, 2007

    To pile on the bandwagon, skimming the paper, it seems to me that his model works not because of quantum effects on the brain, but because the math chosen describes a similar phenomenon—in this case, how probability functions drive which of two discrete states a perceptual system takes on, much like how the Schroedinger equation can be used to predict what energy states a hydrogen atom takes on.

    Unfortunately, the fact that similar equations describe the phenomena in question doesn’t imply that they have a similar physical basis. This looks like an excellent work of mathematical modeling, but doesn’t demonstrate that quantum mechanics is the basis of consciousness any more than the fact that light behaves like a wave implies the existence of the luminiferous aether.

  12. #12 Kurt
    October 26, 2007

    Some researchers who have been critical of previous attempts to use quantum physics to explain consciousness therefore think Manousakis’s model is plausible.

    Not to beat a dead horse here, Mo, but is this just a claim on Manousakis’s part, or do you know of other researchers who have actually said positive things about this line of research?

  13. #13 boojieboy
    October 26, 2007

    I love it how everybody pays attention when a physicist enters the race to explain an interesting psychological phen, but ignores the fact that there are a bunch of contenders who’ve already put their hats in the ring.

    Most of which rely on the knowledge we have of otherwise ordinary neural interactions like lateral inhibition to explain it.

    The problem with this is that it’ll lead to a bunch of “we knew it all along” and “science is finally catching up to us” proclamations from the Fritjof Capra crowd. Just you wait: Deepak Chopra is going to be using this to promote his quantum-mechanical woo any day now…

  14. #14 Tegumai Bopsulai, FCD
    October 26, 2007

    These optical illusions are ambiguous because at any one instant they can be perceived either in one way, or in the other, but not in both… He believes that the ability to flip the image is akin to quantum superposition, in which both possible interpretations co-exist simultaneously in a state that can be expressed as a quantum wave function.

    Oh sure. a phenomenon is which multiple states can exist at once is the most straightforward explanation for a phenomenon in which mutliple states cannot exist at once.

  15. #15 Blake Stacey
    October 26, 2007

    One must carefully distinguish a model of a phenomenon which actually uses quantum physics from a model in which certain mathematical tools are applicable. Linear algebra is a mathematical tool used in quantum physics, but describing a system with linear algebra does not make it quantum-mechanical. Long division and the extraction of square roots can also appear in the solution of a quantum problem, but this does not make dividing 420 lollipops among 25 children a correlate of quantum physics.

    Furthermore, optical illusions arise from mental processing which occurs at a level “before” or “beneath” that which we call consciousness. We don’t choose of our own vaunted free will to see the dancer spinning to the left, or the lines of equal length, or the boxes facing upward: something in our brain does that for us. The “I” can then choose, with a certain “effort of will”, to force the perception into another possibility (the dancer turns in the opposite direction; the boxes flip upside-down).

    A neural network implemented in a computer, with no spooky notion of “consciousness” whatsoever, can be susceptible to “optical illusions” if it is presented with stimuli unlike those upon which it had been trained. The network might, for example, be trained to distinguish up-arrows from down-arrows; its space of possible states would have two attractors and could be modeled with a bistable potential. An “optical illusion” would be an input stimulus which does not have an unambiguous interpretation. With some stochastic noise present in the system, the network’s state could flip from one attractor to the other, changing the perception from up to down.

    Yes, people actually study this kind of thing.

    Since transitions from one perceptual state to another can occur without consciousness, I find the assumption that “conscious awareness is generated anew each time one flips an ambiguous figure” to be unfounded.

    Unlike some theories of quantum consciousness, such as that of Stuart Hameroff and Roger Penrose, this one is testable.

    No, Hameroff’s “theory” is falsifiable, and has by any reasonable standard already been falsified. Decoherence timescales of microtubules are too short, and drugs which disrupt microtubule formation do not affect consciousness. Furthermore, the slim grounds on which it might once have been appealing exist no longer: for example, better explanations of anaesthetic activity have since been proposed, tested and upheld.

    Penrose’s speculations have also met with a chilly reception. First of all, what Penrose wants is not the kind of quantum computing which people are trying busily to do in their laboratories today. Penrose thinks that the laws of quantum physics themselves will have to be modified, so that gravitational effects (in an as-yet-unknown theory of quantum gravity) will allow some kind of “hypercomputation”. Changing well-established physical law to open a special place for a parochial phenomenon only observed in a vanishingly small fraction of space and time is not a practice beloved by physicists.

    The rationale which Penrose gives for why such “hypercomputation” is necessary doesn’t make much sense either.

  16. #16 Blake Stacey
    October 26, 2007

    Also:

    AFAICT, the model doesn’t “explain” the difference between what happens with LSD and without. It just provides a formula for a curve with enough parameters so that the curve can be fit in both cases. I agree with Chad Orzel on this one:

    I’m also a little dubious about calling this a “prediction.” I mean, yes, the model he uses does generate a distribution of switching times with the right general shape, while a different model apparently does not. But it’s really more of a fit than a prediction– the parameters used in the model do not appear to have come from any other measurement, but rather have been chosen to give the best possible agreement between the model distribution and the distributions measured in psychology experiments. Which is fine as far as it goes, but unless you can compare the parameters (a couple of time scales, one for the oscillation and one for the perception of time in the brain) to similar parameters measured by other means, or use those parameters to generate curves for some other condition, you haven’t really proved anything. He applies the model to two different situations (two versions of the same experiment, one involving subjects who were on LSD), but it’s essentially a curve fit both times– none of the parameters are the same, and there’s no explanation for the changes.

    The claim made in the Seed daily zeitgeist that this researcher has “hard data to back up his claims” is, therefore, a little overblown.

    Actually, the graphs look to me an awful lot like Poisson processes, maybe with a little modulation. It’s not that hard to imagine the “dominance” of a perception flipping with a roughly constant average rate. . . .

  17. #17 Amiya Sarkar
    October 26, 2007

    Yet another comment in the fray. As has been pointed out earlier, I also agree that the relevance of quantum superposition and that of EEG were misplaced. However, quantum mechanics, electromagnetic coupling and even string theory are good contenders. In my article ‘consciousness’, I pointed out quite lucidly how it might occur. The vibrations in string theory is also a good contender, in my opinion.
    Penrose and Hameroff did a good job in explaining how decoherence might be averted, so that QM did NOT collapse.

    Physicists or whatever, HAVE to resort to esoteric theories to explain such an elusive and little known entity like this.

  18. #18 Blake Stacey
    October 26, 2007

    If this article ever makes it past the arXiv without attracting some heavy criticism, I’ll be quite surprised.

    It’s not been published in a journal called Quantit. Biol. It’s in the “quantitative biology” section of the miscellaneous paper-pile used by mathematicians and physicists. In other words, it hasn’t been peer-reviewed.

  19. #19 Mo
    October 26, 2007

    Kurt – Frank Nori:

    This is different, its logic is impeccable. This [the LSD result] is a remarkable effect that might prove that consciousness and quantum theory are intimately connected.

    and Henry Strapp:

    If it is correct, this is a landmark paper that for the first time uses quantum mechanics to elucidate brain dynamics and both matches existing experimental data and provides testable predictions.

    From this New Scientist article (subscription required).

    Blake – I had nothing to do with the Seed Zeitgeist. Thanks for pointing out that the paper hasn’t actually been published formally. And thanks for pointing me to Chad’s post.

  20. #20 Blake Stacey
    October 26, 2007

    I don’t know about Nori, but Henry Stapp has his own notions of “quantum consciousness”, and to put it plainly, they’re no good either. For example, he thinks that classical mechanics can’t include correlations between particles, and he thinks that thoughts arise so instantaneously that superluminal signalling is required to zip messages across the brain.

    Amiya Sarkar:

    The vibrations in string theory is also a good contender, in my opinion.

    No, they’re not. Strings are (expected to be) about 10-35 meters across. In fundamental physics, tiny size means lots of energy is required to investigate the phenomenon. You’d need a particle accelerator far more powerful than anything our species has ever built in order to pack enough energy into an interaction to detect its “stringy” properties. There is simply no way that biological organisms can exploit string behavior.

    If living things could tap the possibilities of string theory, then it wouldn’t be so hard to test whether string theory is a viable description of the Universe. We could dispense with the gravity-wave telescopes and the stupendous atom-smashers, and instead do experiments on nerve cells.

  21. #21 Kurt
    October 26, 2007

    I guess it’s not surprising that Nori and Stapp are physicists and not neuroscientists. Although it does look like Stapp has a long history of dabbling in this quantum consciousness stuff.

    This is different, its logic is impeccable.

    That would actually be pretty funny, if it wasn’t (apparently) meant seriously. I have to admit though, after thinking about it a bit, that combining LSD, “flipping” images, and quantum mechanics all together would have been a stroke of comic genius. This New Scientist magazine, it isn’t by chance related to The Onion, is it?

  22. #22 guthrie
    October 27, 2007

    Kurt – no, New Scientist is a UK-based popular science magazine. Its not that bad, but those of us who have been reading it on and off for 15 or more years can remember when it had less speculative stuff and more real science. Maybe publishing it once a week makes them too ready to include really speculative stuff.

  23. #23 Amiya Sarkar
    October 27, 2007

    Blake, I did not mean ‘exploring’ the CNS or whatever with the aid of ‘strings’. I just pondered whether vibrations (a property that is fundamental to string theory; according to this theory all the four fundamental forces and matter may be explained) could ‘synchronize’ neural correlates of consciousness. Question of power does not arise here, since vibration is inherent and coupling would require little energy as a resonant transfer is expected.

  24. #24 David Harmon
    October 24, 2008

    Amusing coincidence: My Mom sent me the right-brain/left-brain meme about the dancer just now. In the course of tracking down your article on that, I noticed this article with my comment just one year (and one late night :-) ) ago.