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Neurons outside the brain
- yichab0d 8mo ago"[i]f you look closely at our nervous system, you’ll see that there are neuronal clusters distributed throughout the body. Human computation is better understood as distributed than centralized."
- pixl97 8mo agoIt's kind of like having a computer at the home, but tens of thousands of computers at a data center. Things like reflexes can happen quickly because you don't have to go all the way to the brain, but your arm isn't going to be adding 2+2 by itself.
- prabubio 8mo agoon the reflexes - does the term "muscle memory" has any truth in it too?
- ACCount37 8mo agoIt's almost entirely in your brain. Less "your muscles remember how to do things" and more "your brain remembers how to do things using your muscles". The muscles and the nerves within your limbs adapt some - they respond to being used - but they don't have the representation capacity to store action patterns in them. The spine itself is another matter - it's much more complex and adaptive, it has some capacity, it can learn things. It mostly carries a set of reflexes you get at birth, and some commonly used learned action patterns. Less "how to play the piano" and more "a set of finger motions useful for playing piano". The most studied thing is probably the spinal involvement in gait generation and stabilization of bipedal locomotion. Now, things would be different if you were an octopus. But humans are pretty centralized, as far as nervous system goes.
- anthk 8mo agoWith 9front you can import devices from other computers. Your body can do the same... with automatic reflexes and even stuff with automatic driving.
- krackers 8mo ago>but it is also possible to live in more harmonious relation between the head, heart, and gut — all the intelligence centers. Aren't those the supposed locations of the "chakras"?
- bitwize 8mo agoGurdjieff was literally, physically correct: we are three-brained beings.
- SoleilAbsolu 8mo agoI'm in the middle of reading "All and Everything" and had the exact same thought!
- baxtr 8mo agoLink?
- deleted 8mo ago[deleted]
- cjameskeller 8mo agoSort of, but it generally goes more like: base/perineum, genitals, navel, heart, throat, forehead, and then one at the top of the head or just above. The Sefer Yetzirah, however, references specifically "Head, Belly, and Chest" as the three loci of the human body. (§ 3.4-5)
- siavosh 8mo agoA very powerful meditation practice is called self-inquiry. One version of it is after you calm your mind down (say with breath meditation) you look for where u think u r. Wherever that is, ask yourself if that’s where u r, what is looking at it? Keep going, don’t intellectualize it, and keep looking.
- xg15 8mo agoBy the same logic, you could ask "what part of a computer 'is' the computer? The CPU? The hard drive? The RAM? The TPM? The power supply? The sum of all peripherals? Etc" You could ask all kinds of philosophical questions about this, but at the end of the day, there are parts that are easily replaceable and parts that are harder if you want to preserve the identity of a particular machine. E.g. while RAM, CPU, GPU, power supply etc are all essential for running a PC, you can also swap them out without many problems. In contrast, the data on the hard drives or the TPM might be hard or impossible to restore. In the same way, I'd still see the brain as the center of the self, because so much cognitive information is stored there.
- hinkley 8mo agoA modern computer looks more like a worm that believes it is self-aware. There are so many SoC subsystems in a computer that the CPU only thinks it knows what's going on and can be catastrophically wrong about it in some cases. Brian Cantrill has a pretty good rant about it in one of the recent Oxide videos.
- hattmall 8mo agoA human is basically just a worm that evolved a lot of extra stuff to feed itself better.
- andsoitis 8mo agoAs a fun fact, humans and worms have a common hypothetical ancestor we call “urbilateria”, likely living over 550-600 million years ago, before the Cambrian explosion. This ancestor gave rise to a branch called protosomes (worms, insects, mollusks) and another branch called deutorosomes (which includes humans and other vertebrates). Worms and humans share: bilateral body organization, a digestive tract, basic nerve structures, many shared genes that control body development.
- hinkley 8mo agoHow dare you sir. I am a high-functioning fungus.
- nlarion 8mo agoInteresting article, Douglas Hofstadter's book https://en.wikipedia.org/wiki/I_Am_a_Strange_Loop https://en.wikipedia.org/wiki/I_Am_a_Strange_Loop takes it a step further and says that parts of our consciousness/soul lives outside of ourselves and in the minds and brains of others. Since one can generally guess how person you know would respond in a given situation, such as how a spouse might be able to know exactly what their spouse would say/do, and in that sense our "souls" are distributed. It's a bit more nuanced than that, but I think that gets the point across of how parts of ourselves live in others.
- kpil 8mo agoI think that is Hofstadter grieving his wife, and reflecting on how we embed models or predictions of others in our own neural networks, more than anything else. We build models of the world in order to predict it. But I guess you could say other people are objectively shaping the neurons in our brains. But so is that fiddly printer tray or whatever, to a small extent.
- conartist6 8mo agoHey that printer tray is a bit of someone's soul too. Many people's work and decisions, even a bit of the nature of our whole society is recorded in those flimsy things. It may or may not be comforting that most of what we contribute to the world will ultimately be considered mundane, even and perhaps especially if it's successful.
- amelius 8mo agoMakes sense. The boundary we draw around a group of neurons that we call "self" is just arbitrary.
- andsoitis 8mo agoThen, logically, we can cut away 90% of your neurons and you will still be there, right?
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- thuridas 8mo agoWhat really called my attention is the personality change after transplants. I am not super sure about how good the science is. Also. We are very neuro-centric, but the system also had all type of hormones and other chemical messages affecting it.
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- stevenwoo 8mo agoThere's a short science book called Hidden Guests, it talks about why women have the potential to end up with microchimeric "incursions" from sexual partners and their own fetuses, fetuses can have microchimerism with each other (not just twins but prior fetuses from same mother) and fetal cells crossing into the mother and towards the end talks about the resemblance between this and transplants( someone else's cells thriving in one's body). So if organ transplants can potentially have that effect, it's already happening to sexually active women, with the caveat that for the fetal cells it wouldn't have much formed personality, yet.
- nickpsecurity 8mo agoI found a good review of it: https://undark.org/2025/11/28/book-review-hidden-guests/ https://undark.org/2025/11/28/book-review-hidden-guests/
- Terr_ 8mo agoThat reminds of a piece which frames pregnancy as a biochemical cold-war between the body of the mother and the child, which can turn "hot" to the detriment of both. In this framing, the chimerism isn't just from cells getting lost, it's the legacy of structured infiltration and sabotage. ______________ > In primates and mice, it’s a different story. Cells from the invading placenta digest their way through the endometrial surface, puncturing the mother’s arteries, swarming inside and remodelling them to suit the foetus. Outside of pregnancy, these arteries are tiny, twisty things spiralling through depths of the uterine wall. The invading placental cells paralyse the vessels so they cannot contract, then pump them full of growth hormones, widening them tenfold to capture more maternal blood. > These foetal cells are so invasive that colonies of them often persist in the mother for the rest of her life, having migrated to her liver, brain and other organs. There’s something they rarely tell you about motherhood: it turns women into genetic chimeras. https://aeon.co/essays/why-pregnancy-is-a-biological-war-between-mother-and-baby https://aeon.co/essays/why-pregnancy-is-a-biological-war-bet...
- red75prime 8mo ago> I find it more plausible that the feeling of speaking from the gut is akin to allowing that center of intelligence coordinate the rest of our body. The author thinks that mentally poking the bodymap created by the brain can cause changes in the actual processing. I wouldn't believe this without proofs other than introspection(1). Technically, the vagus nerve can carry enough information to produce speech (the gut should be articulate, of course), but it certainly nowhere near the corpus callosum or the spinal cord. I doubt that it can allow to "coordinate the rest of our body". (1) As far as know conscious manipulation of the heart rate is achieved by changing respiratory patterns, not thru direct control of the signals that the brain sends there.
- eurekin 8mo agoThe first time I heard of how many neurons the gut has, I went: "well obviously, there's a lot of receptors and muscles to support peristaltic movement; plus probably some start to end connection for proper synchronization and total volume management - it just has to be processed somehow and locally (in the gut, as opposed to the far brain) seems like an obviously good choice". Never tried to verify that with state of the art though
- CephalopodMD 8mo ago> In several cases, memories of the old heart’s host seem to become accessible to the recipient ^2. That does not seem at all to be what citation 2 is saying.
- ahoka 8mo agoThat's where I have stopped reading.
- m4x 8mo agoThere's a case cited in that paper which does suggest something similar: > A report in the lay literature describes the case of Claire Sylvia who reported changes in her personality, preferences, and behaviors following a heart and lung transplant at Yale-New Haven hospital in 1988. Following surgery, Sylvia developed a new taste for green peppers and chicken nuggets, foods she previously disliked. As soon as she was released from the hospital, she promptly headed to a Kentucky Fried Chicken to order chicken nuggets. She later met her donor’s family and inquired about his affinity for green peppers. Their response was, “Are you kidding? He loved them… But what he really loved was chicken nuggets” (p. 184, [9]). Sylvia later discovered that at the time of her donor’s death in a motorcycle accident, a container of chicken nuggets was found under his jacket [9]. I haven't read the whole thing, maybe there's something more relevant as well. That report isn't really about accessing the previous persons "memories" but at least claims she adopted a part of their personality. I'd be skeptical about its accuracy without more such reports, however.
- easyThrowaway 8mo agoA safer assumption would be that our body influences our behavior and tastes, and in turn they are directly affected by changes in our body, like an organ transplant. A more interesting question regarding the case above would be "what's in our hearth and lungs that affects our perception of capsaicin?".
- raincole 8mo agoIt's still way, way too different from > In several cases, memories of the old heart’s host seem to become accessible to the recipient
- sriacha 8mo agoSee Michael Levin.
- bandrami 8mo agoI shocked a lot of flatworms for that guy 20 years ago. Really cool stuff.
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- david_draco 8mo ago> What does it mean that that I feel my anxiety in my gut? And that I clearly feel when I’m speaking from my head or my heart (or both)? [...] What does it mean that that I feel my anxiety in my gut? And that I clearly feel when I’m speaking from my head or my heart (or both)? An unjustified logical jump here seems to be that where you feel your thoughts and feelings are coming from is where the responsible neurons are. The assignment of the feeling of origin may be a separate mechanism.
- xattt 8mo agoThe article reads like a naïve person coming to terms with the idea of consciousness… like “whoa maaan, my fingers… they’re finging!” “Extra-cerebral” neurons are optimized for different functions than neurons proper in the brain. It’s unlikely that the gut has thoughts and feelings, given neuronal tissue is distributed throughout viscera (versus concentrated in one spot like the brain). They are distributed so that smooth muscle tissue can contract appropriately and push food and wastes down the line. The author compares the number of GI neurons to the number of neurons in a dog’s brain, but gleans over the number of neurons in a dog’s GI tract which is probably similar or proportionally less because the tract is physically smaller. The neurons the author highlights in the heart are concentrated at the base, because the shape of the heart is optimized for coordinated contraction via electrical impulse propagation.
- killerstorm 8mo agoI think people are just confusing cause and effect here. Anxiety triggers release of hormones like adrenaline and cortisol, which trigger a host of physical symptoms ranging from cold hands (reduced blood flow in extremities) to upset stomach, nausea, increased heart rate, etc. Brain can anticipate these changes and associate anxiety with the effects of these hormones. There might be all sorts of interesting interactions, but saying that gut is responsible for processing of these feelings is definitely a stretch. Another physical reaction which is associated with an emotion is blushing. But somehow nobody is talking about face skin taking control...
- justonceokay 8mo ago
- Schlagbohrer 8mo agoAny discussion of embodied intelligence or the realization of how much of our nervous system is outside of our brain makes thinking about genital mutilation (such as non consensual infant circumcision) even more horrifying. How many nerves are lost when intersex children or infant boys are mutilated?
- lloydatkinson 8mo agoValid points, but will be hopelessly flagged and deleted before long.
- krzat 8mo agoThe assumption that neuron activity == consciousness is incorrect. A lot of neurons in our brain are doing visual processing. How much of it is conscious? Writing this comment, I have very little insight into how I am able to create this sentence and then read it. Makes me wonder what's the point of being conscious anyway.
- andai 8mo agoWell, I can provide a thought experiment I did back in high school... imagine a universe identical to ours, except that nobody was conscious. There would be "no one there" to experience it, by definition. So would such a universe exist?
- ASalazarMX 8mo agoI guess yes? Why would it cease to exist if no one experienced it? It wouldn't change its physical properties.
- NuclearPM 8mo agoThat question isn’t as deep as you think it is.
- andai 8mo agoIf we accept the existence of that which cannot by definition be observed in any way... then is that not an infinitely large category?
- ASalazarMX 8mo agoThese kind of trick questions are variations of the tree falling when no one heard it. They aren't asking "did it generate soundwaves?", they're asking "if sound included perception, did it make a sound?". It's weird to ask questions like these outside quantum mechanics, where observation actually affects the result. https://en.wikipedia.org/wiki/If_a_tree_falls_in_a_forest_and_no_one_is_around_to_hear_it%2C_does_it_make_a_sound%3F https://en.wikipedia.org/wiki/If_a_tree_falls_in_a_forest_an...
- seniortaco 8mo agoFrom an evolutionary perspective, it makes sense that the body would explore all possible ways to increase intelligence, with neurons located anywhere in the body and with chemical in addition to electric signals. It's not like a car or something that was designed with specific functions for specific components.
- anthk 8mo agoMore related stuff. https://www.researchgate.net/publication/365412617_Polyatomic_time_crystals_of_the_brain_neuron_extracted_microtubule_are_projected_like_a_hologram_meters_away https://www.researchgate.net/publication/365412617_Polyatomi...
- deleted 8mo ago[deleted]
- 47282847 8mo agoAnyone here into Systemic Constellations and have a theory of how they work?