1. Sign our petition calling on Cochrane to withdraw their review of Exercise Therapy for CFS here.
    Dismiss Notice
  2. Guest, the 'News in Brief' for the week beginning 18th March 2024 is here.
    Dismiss Notice
  3. Welcome! To read the Core Purpose and Values of our forum, click here.
    Dismiss Notice

[Preprint] A mind-body interface alternates with effector-specific regions in motor cortex, Gordon et al, 2022

Discussion in 'Other health news and research' started by cassava7, Oct 29, 2022.

  1. cassava7

    cassava7 Senior Member (Voting Rights)

    Messages:
    985
    Primary motor cortex (M1) has been thought to form a continuous somatotopic homunculus extending down precentral gyrus from foot to face representations. The motor homunculus has remained a textbook pillar of functional neuroanatomy, despite evidence for concentric functional zones and maps of complex actions.

    Using our highest precision functional magnetic resonance imaging (fMRI) data and methods, we discovered that the classic homunculus is interrupted by regions with sharply distinct connectivity, structure, and function, alternating with effector-specific (foot, hand, mouth) areas. These inter-effector regions exhibit decreased cortical thickness and strong functional connectivity to each other, and to prefrontal, insular, and subcortical regions of the Cingulo-opercular network (CON), critical for executive action and physiological control, arousal, and processing of errors and pain.

    This inter-digitation of action control-linked and motor effector regions was independently verified in the three largest fMRI datasets.

    Macaque and pediatric (newborn, infant, child) precision fMRI revealed potential cross-species analogues and developmental precursors of the inter-effector system. An extensive battery of motor and action fMRI tasks documented concentric somatotopies for each effector, separated by the CON-linked inter-effector regions. The inter-effector regions lacked movement specificity and co-activated during action planning (coordination of hands and feet), and axial body movement (e.g., abdomen, eyebrows).

    These results, together with prior work demonstrating stimulation-evoked complex actions and connectivity to internal organs (e.g., adrenal medulla), suggest that M1 is punctuated by an integrative system for implementing whole-body action plans. Thus, two parallel systems intertwine in motor cortex to form an integrate-isolate pattern: effector-specific regions (foot, hand, mouth) for isolating fine motor control, and a mind-body interface (MBI) for the integrative whole-organism coordination of goals, physiology, and body movement.

    Preprint: https://www.biorxiv.org/content/10.1101/2022.10.26.513940v1

    Twitter thread by the first author (explains what the motor homonculus is):

    https://twitter.com/user/status/1586026653402402818
     
    Peter Trewhitt likes this.
  2. John Mac

    John Mac Senior Member (Voting Rights)

    Messages:
    905
    All totally over my head but i did like this twitter response

     
    bobbler, Lisa108, alktipping and 2 others like this.
  3. cassava7

    cassava7 Senior Member (Voting Rights)

    Messages:
    985
    Surely, textbook rewrite worthy discoveries such as this work (Penfield’s motor homonculus model dates from 1948) should prompt neurologists and psychiatrists to remain humble about our limited knowledge of the brain.
     
  4. rvallee

    rvallee Senior Member (Voting Rights)

    Messages:
    12,299
    Location:
    Canada
    Sometimes I wonder if by mind they don't mean soul because I have no idea what this has to do with some imaginary boundary between the brain and some spiritual or whatever concept of "the mind".

    Trying to cram old ideas into research just because those ideas are obsessively believed is a terrible, absolutely awful idea.
     
  5. cassava7

    cassava7 Senior Member (Voting Rights)

    Messages:
    985
    One of the authors made this point:
    https://twitter.com/user/status/1586320715573211136


    “Mind” in this work is presumably to be understood as “planning voluntary movement”.
     
    Last edited: Oct 29, 2022
  6. Jonathan Edwards

    Jonathan Edwards Senior Member (Voting Rights)

    Messages:
    13,278
    Location:
    London, UK
    They are all talking through their hats.
    The distinction between soul and brain is entirely legitimate. Descartes's dualism was well founded but a bit wrong in detail.

    The mistake here is to think that areas of brains have functions where they sit. The only function of a brain cell is the way it joins to a cell somewhere else so this approach goes nowhere. The way the top-to-bottom series of face, hands, legs etc. is copied in motor cortex has nothing to do with function any more than the packing of telephone wires at an exchange does. It is just convenience. The function is in the cross connections.

    The findings are quite interesting but calling it mind-body interface is silly. Even if they pretend they do not really mean it, it is used to make the studies sound sexy.
     
    ukxmrv, bobbler, FMMM1 and 5 others like this.
  7. Shadrach Loom

    Shadrach Loom Senior Member (Voting Rights)

    Messages:
    1,052
    Location:
    London, UK
    Wow. Even if by “soul” you mean “consciousness” that’s quite a large claim. Dualists from Descartes to Nagel have been outgunned philosophically by materialists and functionalists every time some novel way is found to pretend there is such a thing as a “mind-body problem”.

    Gilbert Ryle is definitely not fashionable but his notion of a “category mistake” is still quite useful when people start rabbiting on about qualia, or even when they start trying to interest people in tensions between free will and determinism. His best example of a category mistake is an angry tourist in Oxford asking his guide where the actual university is, after only being shown colleges.
     
    Last edited: Oct 29, 2022
  8. Jonathan Edwards

    Jonathan Edwards Senior Member (Voting Rights)

    Messages:
    13,278
    Location:
    London, UK
    Nope. Descartes was a physicalist anyway - his duality was within his physics, between action and inert extension - which all subsequent physics makes use of. The academic story on this is all guff. Nagel probably missed the point, I agree.

    Materialism is a nonsense if it is based on 'matter'. Remember that Einstein pointed out (quoted in my last paper but one) that physics is just a way of defining the mathematical rules that link experiences. Modern physics abandoned any idea of matter beyond that.

    Functionalism is just wrong. A screwdriver has two functions - to unscrew screws and to open paint tins. So function tells us nothing about anything much - except as Chalmers let out of the bag, at the finest grain, but then it ceases to mean anything to call it functionalism.

    The events that we report as phenomenal experiences are at a completely different level from 'brain' so I think it is legitimate to try to pin down 'soul' domains. Descartes's arguments are pretty hard to beat as I see it - other than of course by Leibniz, who does better still.

    All a bit hard to condense into a forum post but basically the analytic philosophy crowd have been talking themselves round in badly informed circles for rather too long now. And of course the continentals are just barmy.
     
  9. Shadrach Loom

    Shadrach Loom Senior Member (Voting Rights)

    Messages:
    1,052
    Location:
    London, UK
    I’d absolutely agree that analytic philosophy of mind probably focuses way too much on the epistemic status of autophenomenological experience, and that continentals are barmy. Leibniz did invent good biscuits, though.

    But it’s the modern physicalists such as Dennett who do the best job of accommodating current neuroscience within a satisfying account of consciousness as an emergent property, rather than a locatable one. Which is essentially why this sort of paper is as perturbing as old Rene suggesting that the pineal gland was a good bet.
     
  10. Jonathan Edwards

    Jonathan Edwards Senior Member (Voting Rights)

    Messages:
    13,278
    Location:
    London, UK
    Nonsense. Dear old Dan is good company but has no idea of what physical science is about. I think he trained with Ryle, which would have been a bad mistake. Phenomenal experience is the one thing we are certain of, as old René had it. The idea that you can get propositional meaning and propositional attitudes out of the function of sending signals around is ludicrous. Not that I am suggesting some 'other magic' beyond the processes that physics describes (which end in experiences), simply that the inside of those processes is a lot more interesting than a game of billiards.

    The 'intentional stance' is about as barmy as Deleuze.
    The stuff about emergent properties is complete bullshit - whether Tononi or Friston or whoever. It isn't even possible within physics, so it is more dualist than any.

    What Dan did get right though, I think, is the multiplicity of events of experience - not just drafts but the whole thing, fully polished, in massive multiplicity.
     
    alktipping and Peter Trewhitt like this.
  11. rvallee

    rvallee Senior Member (Voting Rights)

    Messages:
    12,299
    Location:
    Canada
    This does not clarify anything and is laughable considering, frankly, literally everything coming out of this ideology. All this talk is just as useless as everything said about physics and the universe before real science gave the right answer. Problem is that medicine doesn't have math to provide reliable proofs, so they get stuck talking about the equivalent of phlogistons and luminiferous aether and whatever, on and on forever.

    Reminds me of this, this square hole can fit so much BS:

    https://www.youtube.com/watch?v=jkz7bnYfuOI


     
  12. Shadrach Loom

    Shadrach Loom Senior Member (Voting Rights)

    Messages:
    1,052
    Location:
    London, UK
    This argument is as old as time and it always, always ends with everyone accusing everyone else of being a dualist.

    It’s intriguing to encounter a neo-Leibnizian on an ME/CFS forum, though. Do you have a biophysical theory of monads? Do you want all atoms to be conscious, or just cells, or solely brain cells, or only sufficiently complex (yet locatable) arrangements of neurons and dendrites, conferred with epiphenomenality as an adaptive advantage?

    I’m not unsympathetic to the idea. Like you, I enjoy Dennett’s account of multiplicity. Consciousness is certainly much less coherent, consistent and unified than we like to pretend.
     
    alktipping and Peter Trewhitt like this.
  13. Jonathan Edwards

    Jonathan Edwards Senior Member (Voting Rights)

    Messages:
    13,278
    Location:
    London, UK
    @Shadrach Loom
    Yes, some details are given in my recent J Consciousness. Studies papers but the main exposition is in my 21st Century Monadology (2014)

    https://www.researchgate.net/publication/260273368_A_21st_Century_Monadology

    The monad is the true atom of nature, with no figure or extension, characterised by a constant internal principle of change or force (Heidegger suggests drive) present a all scales, with internal complexity but no parts. It exists at the fundamental (metaphysical in 1714) level.

    That is a very neat description of modes of excitation of fields in current extended QFT. So not atoms as in Rutherford. Atoms of action. In modern terms the scale fizzles out small at the wavelength of a gluon or time span of a Higgs mode, unless you go for quantum foam, and large at rotatory modes of galaxies based on breakage of symmetry of the Fermion field densities with the spiral shape, but I don't think Leibniz was too far wrong.

    As Leibniz points out, modes in brain owe their rationality, and apperceptive 'consciousness' to being helped out by vast numbers of other animalcular modes in other body tissues and surrounding brain, which bring in and collate signals and set up representations that are fed in through light-like (EM) signals to vibrating membranes inhabited by the higher monads (from New Essays) - pretty much what current neuroscience says.

    Monads like photons will 'perceive' in the sense of being informed by ambient fields, but in a confused way that we cannot expect to be able to envisage. They are not conscious in that their perceptions do not represent anything or draw on memories etc.

    So the monads whose experiences we talk about as our experiences are privileged in having well organised information coming in. But in my last couple of papers I have also explored the possibility that collective Bose modes - which include the modes of sound and the organised rotations that make medium sized dry goods 'objects' to us - have two different forms of input. This is very technical and has to do with ladder operators but in simple terms some inputs define the nature of the mode itself and others 'tweak' it as time goes by, up or down some energy levels. That means that such modes can separate the information that just makes them what they are from information about current goings on.

    Both Descartes and Leibniz were right to point out that the subjective soul must be a single unit, not a series of units linked in sequence like a neural net. So neural nets cannot be monads. Individual cells can, and I suspect Leibniz saw the soul as a monad in one brain animalcule, after his experience with Leeuwenhoek's microscopes. Travis Craddock has proposed very plausible monadic collective modes in cytoskeletal assemblies in dendrites. They appear to be 'fired up' by blue light photons, maybe during waking. Presumably the photons normally transfer locally from mitochondrial events.

    So I think we are getting near to a plausible theory of 'soul'. The only problem is that philosophers, physicists and neuroscientists alike cannot get past naive intuitions about a single self floating about in a nerve network.
     
    Shadrach Loom likes this.
  14. Shadrach Loom

    Shadrach Loom Senior Member (Voting Rights)

    Messages:
    1,052
    Location:
    London, UK
    @Jonathan Edwards

    Thanks for setting that out. I’m out of my depth with the science. I can almost see how modern physics might help one to treat consciousness as an intrinsic property of sufficiently informed neural components. I can see that once you build on those foundations, talk of “emergent”, non-intrinsic properties by scientifically-illiterate physicalists will seem like a hand-waving avoidance of the important questions. But although I’ll read your paper with interest (and I’m deeply, genuinely impressed by your polymathery in making a significant contribution to monadology in addition to eminence in rheumatology and the triple jump) I suspect I will struggle with the detail and be unable to comment.

    One quick point, though, before I dive in. If you explain it elsewhere, all well and good. Can I just check again that there is nothing theological in your concept of the soul? It’s a word that most post-Enlightenment philosophers tend to avoid, although it’s not unhelpful to use a single four letter word for the experience of being a conscious entity with a notionally consistent identity over time.

    So it’s worth establishing whether souls, in your usage, wink into being at some point following conception and disappear for good after death, and that there’s no notion of eternality or reincarnation beyond the ultraminimal ones which are presumably inevitable if monads obey the law of conservation of energy.
     
    FMMM1 likes this.
  15. Jonathan Edwards

    Jonathan Edwards Senior Member (Voting Rights)

    Messages:
    13,278
    Location:
    London, UK
    I do not have any interest in organised Abrahamic creeds. But I was convinced by Leibniz that we have to postulate some form of Necessary Being that provides the reasons why we live in a cosmos in which everything follows beautifully regular rules effortlessly. The Being has no location in place or time and is not a cause, so was not 'there before creation'. It is just a totality of reasons, like the rules of chess.

    I am not impressed by claims of 'intelligent design' suggesting that we can attribute a purpose to the Necessary Being. Partly because the intelligent design freaks want the physics to be supplemented by magic tweaks and any really intelligent designer would just build that into the physics. But I think it may be a mistake to rule out the possibility that we live in a cosmos that has some 'end' set out and that the 'reasons' do have some sort of 'purpose'. Since we have no clue as to how the reasons work we are not in a position to pooh-pooh. I have a paper on telic aspects in the 2016 International Leibniz Conference Proceedings.

    But I do not follow Leibniz's desire to have souls as immortal. I am afraid that I think they are rather evanescent. Nevertheless, I think Leibniz's reasoning is very cogent - it is just that his practical application of the arguments does not quite work the way he would like. Modes of excitation in QFT are in a sense immortal, but it all gets very abstract and irrelevant and misleading to make use of that to make souls immortal.

    The physics is very easy. No need for complex harmonic oscillation equations. You just have to note that wherever there is an asymmetry in the cosmos that allows a specific way of oscillating you have a mode of excitation, at least the ground state. If the cosmos was exactly the same throughout there would be no specific wavelengths or frequencies to make use of. As soon as you break symmetry options arise. The way that gives us electrons is very technical and obscure but the way it gives us modes at a biological scale is easy because it is more or less like sound waves. The reasons why brains won't do is to do with very simple systems dynamics. Leibniz worked all the important bits out without Schrodinger's equation.
     
    FMMM1 likes this.
  16. TiredSam

    TiredSam Committee Member

    Messages:
    10,482
    Location:
    Germany
    Blimey chaps.
     

Share This Page