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rendx | on: Not alive, but not dead: disembodied human brains used for drug testing
Can you point me to a paper or other source that proves that the brain is the seat of consciousness? Or that disproves other theories?

I am familiar with the works of Oliver Sacks, Paul Broks, and others, who have spent their lives researching damage to brains and the potential consequences for the psyche. I agree that it sounds like damage to the brain can have big impact, but none of that research, as far as I am aware, proves or even tries to argue that the brain is the only component necessary for consciousness to exist.

I am not interested in beliefs in one theory over another. I am not even asking for probabilities. I am asking for a scientific approach, which is to detail all possible (potentially fringe) theories until they're proven wrong. Anything else is the business of religion.

    Singer, J., & Damasio, A. (2025). The physiology of interoception and its adaptive role in consciousness. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 380(1939), 20240305. https://doi.org/10.1098/rstb.2024.0305
We think that organs can be replaced with little apparent change in consciousness (- this is an active research area, too, by the way). There is also research into how body tissues may form a part of what other theories place exclusively in the brain.

    Aderinto, N., Olatunji, G., Kokori, E., Ogieuhi, I. J., Moradeyo, A., Woldehana, N. A., Lawal, Z. D., Adetunji, B., Assi, G., Nazar, M. W., & Adebayo, Y. A. (2025). A narrative review on the psychosocial domains of the impact of organ transplantation. Discover mental health, 5(1), 20. https://doi.org/10.1007/s44192-025-00148-y
> "Having its own enteric nervous system, sometimes referred to as the “second brain,” the gut is also an immune organ and has a large surface area interacting with gut microbiota. The gut has been shown to play an important role in many physiological processes, and may arguably do so as well in perception and cognition."

    Boem F, Greslehner GP, Konsman JP and Chiu L (2024) Minding the gut: extending embodied cognition and perception to the gut complex. Front. Neurosci. 17:1172783. https://doi.org/10.3389/fnins.2023.1172783
cogman10 | parent | next
Ok, I've actually read into the 3 articles you've suggested and none of them are making the argument you are making. I think you just title mined.

Article 1. is about how the brain interprets incoming signals from the body

Article 2. is about dealing with psychiatric needs, such as medication compliance and stress, which result from organ transplants.

And, as I addressed in another comment, Article 3. is a discussion about the impacts of gut microbiome on mood. It is not a discussion of "consciousness".

cogman10 | parent | next
Three are a million case studies and studies on it. So much so that you'll find studies on the best ways to repair consciousness after traumatic brain injuries [1].

You can't find a single case study where someone's consciousness was notably altered due to bowel resection. Something that has happened all the time.

Where are the people losing or having alerted consciousness after having their stomachs stapled? Their perforated bowels resected? Their bowel cancer polyps removed?

The closest you'll find is soldiers suffering from, understandable, PTSD.

Also, I'd point out that the studies you referenced aren't suggesting your point. They are saying that the gut can affect our mood and cravings. But as anyone that's taken a powerful antibiotic can attest, that did not modify their consciousness even though it nuked a huge portion of their biome.

People also get fecal transplants, they don't share consciousness as a result.

Unless you want to define consciousness as an eternal soul that exists in rocks, then you'll find no support for the suggestion that it exists outside a brain.

You also need to explain why it is that traumatic brain injuries alter consciousness and memory. Why it is that we can observe physical changes in the brains of dementia patients.

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC2931585/

rendx | root | parent
Agreed.

Let's wait and see what happens with brain or head transplantation. :)

rcxdude | parent
If you're going full philosophy of science, are these alternative theories falsifiable in the first place? Much of this kind of argument turns into philosophy and metaphysics instead of empirical science.
rendx | root | parent
Imagine what would happen if we transplanted a head, or full brain, and the consciousness self would still remain the same, like with other organ transplantation.

We'll see!

I am saying: we can guess, but we don't know. I am not saying it's likely. I just want to remain precise in what are theories. It is a theory that consciousness "lives" inside the physical brain, as much as it is one that it doesn't. It is physically possible that it exists energetically and moves and stays with "the larger chunk of body".