Neuronal Panpsychism

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Panpsychism is the view that everything has a mental life. Many people find this implausible because it seems weird to think that rocks and dust bunnies are cognizers in the same way that people or animals are cognizers. Panpsychism also seems to contradict the growing consensus among neuroscientists who claim that consciousness only “arises” when a certain level of cortical connectivity or information integration is present in the brain, especially in fronto-parietal circuits and other “global workspaces”.

But why think you need a sophisticated network of cortico-cortical activity in order to have a mind, to have a point of view on the world? Why not think a single neuron is a locus of mental experience? Perhaps there is a faint “something-it-is-like” from the point of view of individual neurons. I call this view neuronal panpsychism: it says that every neuron has a distinct mental life independent of its interaction with any other neuron. Of course a neurons experience is going to be significantly impacted by its causal and reciprocal interaction with neighboring neurons but the point is that the neurons themselves are loci of experience in virtue of their intrinsic nature.

But how do we account for the reams of data suggesting that a high-level of connectivity is necessary for what Stan Dehaene calls “conscious ignition”? After all, even coma patients have some preserved neuronal activity but no one thinks they are conscious: they show no external signs of consciousness at least.

The key to explaining this data in a way that’s consistent with neuronal panpsychism is the “nesting” solution. The idea is that the “macro” consciousness of normal human adults is actually composed of the “micro” experiences of all the individual neurons. The feeling of global unity is therefore an illusion according to neuronal panpsychism. The feeling of being one great unified stream of experience is actually an aggregate of billions of microexperiences in the same way that a river is composed of countless water atoms.

But what does it mean for experiences to “add up” in this way? Is there an equivalent of multiplication or taking the integral? These are tough, unresolved theoretical issues facing all brands of panpsychism. But is it any less mysterious than saying consciousness “arises” whenever informational connectivity reaches a certain threshold in frontal-parietal circuits or when there is 40z synchrony or whatever?

I actually think though neuronal panpsychism can make sense of why it feels different to have your frontal-parietal circuits activated or deactivated and why these circuits seem to make both a significant phenomenal and functional difference to the “macro” level experience of normal human adults. Neuronal panpsychism says that all neurons have mental states but that doesn’t mean they all have the same kind of mental states. For example, a motor neuron might have a different experience than a Von Economo neuron, or a cerebellar neuron might have a different experience than a neuron than lives in the prefrontal cortex.

In effect neuronal panpsychism is a kind of microfunctionalism where neurons with different functional profiles have different mental lives. These functional differences arise from both their phylo and ontogenetic history i.e. different types of neurons have different inherited genetic programming but they also have unique, individualized learning experiences.Thus. the differences in felt macro experiences when there are high levels of frontal-parietal activity are due to the unique experiences of those neurons being added to the choir of subcortical neurons. But they are not the origin of phenomenality, only the “loudest” phenomenality or “most famous” phenomenality, to borrow a metaphor from Dan Dennett’s “fame in the brain” theory (which is an intellectual precursor to neuronal panpsychism).

Thus, when a vegetative patient is transitioning to the minimally conscious state and onwards to normal consciousness there is never one unique threshold when consciousness gets “turned on”. Consciousness is not all or nothing. Consciousness is not a special property of only a unique set of cortical circuits in mammals with sufficiently activated global workspaces. According to neuronal panpsychism, ALL neurons contribute to what-it’s-like to be a unified mind or “I”.

But why stop at neurons? Why not think glial cells have mental lives too? Indeed, why not claims all cells have mental lives? This would be “cellular panpsychism”. But that’s another post.

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10 responses to “Neuronal Panpsychism

  1. I’ve seen ideas resembling these before, but I find them very difficult to make sense of. I wonder whether they have any empirical content at all. If your idea is “correct” (whatever that might mean), does it have any physically observable consequences?

    Regards, Bill

    • Hi Bill,

      Neuronal panpsychism is an idea concerning the fundamental metaphysics of consciousness. It’s not meant to have “empirical content” in the way, e.g., the theory of evolution has empirical content.

      I agree with Wilfred Sellars who said that “The aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term.”

      Neuronal panpsychism would be a way to see how things hang together. It’s not about making predictions but about clarifying concepts and seeing the forest for the trees.

      How do you think we might go about solving the mind-body problem? Do you deny there is a problem? I suspect that for any proposed solution to the problem there is going to be some philosophical aspect not directly amenable to empirical refutation. But there are a lot of things not amenable to empirical refutation e.g. can science refute the claim that a bachelor is a unmarried male? No, because the truth status of the claim is in virtue of its nature as a concept. It would be silly to try and build a “bachelor-o-meter” to detect whether all bachelors are REALLY unmarried males.

      I suspect at some level debates about consciousness are operating at this conceptual level. Neuronal panpsychism is a contribution to debates happening at that conceptual level. Scientists dont have to care about neuronal panpsychism to go about doing experiments but philosophy operates at a much more abstract level so that’s fine. Not all good philosophy needs to make an impact on what scientists do with their time.

      • Let me use an analogy to try to clarify what bothers me. I look around me and I see that many things in the world are evil. So I propose the theory of “pan-villainousness”, which claims that everything in the world contains some level of evil, and the evil of an entity is the accumulated evil of its parts.

        Is your theory any better than the theory of pan-villainousness? If so, why?

      • I hesitate to call the idea developed in this post a “theory”. It’s more like a conceptual framework.

        But the problem with your analogy is that there is no “Hard problem of evil”. People aren’t theorizing about evil, nor do theories of evil have a 2,000 year philosophical history. Nor do people call “evil” the greatest scientific puzzle of our time.

        Neuronal panpsychism is a functionalist approach to the metaphysics of consciousness in the same tradition as other materialist metaphysics of mind. For example, take J.J.C. Smart’s “type identity theory” solution to the mind-body problem. Smart famously said mental processes are identical to brain processes. Neuronal panpsychism is similar to this idea but slightly different in the details. It’s not a scientific theory. It’s a rebuttal to people who think the mind cannot possible be reduced to physical matter. It’s an alternative worldview to Cartesian dualism.

        Do you just think that debates about behaviorism, dualism, identity theory, eliminativism, functionalism, etc. are worthless? It sounds like you just don’t have any appreciation for philosophy of mind. Which is fine. But others like myself do so I will continue to think about these things because they’re philosophically interesting and not because they immediately lend themselves to the day to day drudgery of science.

      • (This is actually a reply to Gary’s reply to me, which hopefully will appear directly above.)

        On the contrary, I am very interested in the philosophy of mind — I have been working for several years on a book about the study of consciousness. But my view is that if ideas have no practical consequences whatsoever, then they are merely strings of words and don’t actually mean anything.

        Also, I find the phrase “day to day drudgery of science” to be, um, interesting.

        Regards, Bill

  2. Gary: “I suspect that for any proposed solution to the [mind-body] problem there is going to be some philosophical aspect not directly amenable to empirical refutation.”

    On the other hand, empirical findings certainly have to be taken into account in formulating a reasonable philosophical assertion about the mind-body problem. For example, how would neuronal panpsychism account for the vivid hallucination evoked in the SMTT experiment described here: http://people.umass.edu/trehub/YCCOG828%20copy.pdf

    • Tweak

      Very interesting post there Gary. I’m not sure if your familiar with biosemiotics, but your neuronal pansychism has great affinities (understood in a certain way) with it. Or the endosemiotic branch of biosemiotics at least. Though in biosemiotics we would refrain from using the term pansychism, since we are only referring to neurones as living systems in their own right, which partake in semiosis.

  3. amanimal

    Hi Gary, an interesting read – brought to mind:

    ‘Nano-Intentionality – A Defense of Intrinsic Intentionality’, Fitch 2008
    http://homepage.univie.ac.at/tecumseh.fitch/wp-content/uploads/2010/08/Fitch2008NanointentionalityCorrect.pdf

    … unfortunately the philosophic nuances are still a bit beyond me, but I enjoyed both Fitch and your post – thanks!

    Mark

  4. I think the real issue is that sure, panpsychism may “feel” weird, but emergentism is every bit as weird and unprovable. Where people fall is just a matter of their jumping off point and what fits with the other ideas they’ve already lined up.

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