An ostracized brain

[Tea Earl Grey Hot]

I've wondered for a while, if someone were able to develop a real live human brain without any physical body whatsoever, would a self aware person still develop or would it be just a clump of cells no more intelligent than a plant? This brain would at no point in its life have access to experience the outside world through the five senses. What do you think would be going on in such a brain?

[Foxaèr]

It depends if the brain was connected to virtual reality. If that was the case, the brain could very well perceive its made up world as reality and believe it is inhabiting the body in which it finds itself in that world.

[Tea Earl Grey Hot]

It depends if the brain was connected to virtual reality. If that was the case, the brain could very well perceive its made up world as reality and believe it is inhabiting the body in which it finds itself in that world.

It's not. It's just sitting there staying alive.

[Foxaèr]

I imagine it would be similar to a mixture of sensory deprivation and lack of societal influences, where a wild personality was formed. The brain would form its own reality and its own rules in which to exist in that reality, but of course there probably would not be many rules since it cannot interact with anything except itself.

[pineapplebunnybounce]

This is very hard to speculate on because almost everything we know and think about are based on what we understand from our perception of the environment. If you don't perceive anything ... there's no framework to build upon. Hmm. The brain is able to recognize self and nonself when intact with a body, there are people who get brain damage and think that their left arms belong to someone else because the brain can no longer recognize it as self. But if your brain just sits there, what is it supposed to recognize as self? It cannot feel it's own existence. So i wonder if there's even a concept of self to develop a "person" around.

[Cato]

I've thought about this from time to time. My initial reaction was that the brain would never become self aware without external stimuli with which to process and differentiate itself.

I then thought about the various gauges and meters used to 'process' input in my time on submarines and then wondered what the brain's default position was. Gauges and meters without input will fail to a certain condition, usually high or low. Let's just talk about hunger.

The brain is not the blank slate that Locke assumed (no marks against Locke here, psychology and neuroscience were yet to be discovered). Does the part of my brain that processes hunger fail high or low? Meaning, is the normal state always hungry or always satisfied before processing the input? Infants cry when hungry. Is this because there is a signal given to the brain when the stomach is empty, or is there a lack of signal given when the stomach is empty? Your created brain will either produce an output or not depending on how this relationship works.

Extend this to quasi-involuntary functions like breathing. I can hold my breathe, but I have never been able to make myself pass out before control of my diaphram is relinquished to my medulla oblongata.

I apologize to a certain extent for my lengthy reply; however, I wanted to put my conclusion in context. In your thought experiment I conclude that the petri-brain cannot become self aware, but proclaim that such a condition would be 'worse' than a plant in that the outputs of evolutionary brain function would be rendered meaningless without a body to interact with.

I'm not certain if this is what you were getting at, but there is no mind-body dichotomy.

Great thread.

[Minimalist]

It depends if the brain was connected to virtual reality. If that was the case, the brain could very well perceive its made up world as reality and believe it is inhabiting the body in which it finds itself in that world.

As good an explanation for the Tea Party as I have yet heard!

[Lucanus]

I tend to think it would be much like an empty HDD with an idle OS that could go on and on being idle as long as it recieves the nutrients it needs. An incredibly complex, carbon based one, but still. And just as soon as it recieves some input, it starts working even on its own.

I may just as well be horseshitting you however.

[Rahul]

No idea. But it's going to be batshit insane in no time. It wouldn't even understand what language was so it couldn't even articulate itself in speech. Or be able to form mental images or sensations or anything. But it would go through the sleep/wake patterns.

And being utterly alone, this social animal's brain, it would be in a living hell.

I would "accidentally" trip over the cord to the life support system. Oops. Subject 438 was accidentally terminated at 1937 hours on July 27, 2013. End of file.

[Angrboda]

A few random points. First, the brain is born with basically all the neuronal connections it will ever have, the brain is mostly shaped by removing neural connections and altering the strength of connections between neurons. Without experience, it's doubtful the brain would develop in any kind of normal way. Many developmental stages require stimulation to occur, and it's generally presumed that a total lack of input would result in a great lack of development, and what development might occur would be grossly distorted and likely dysfunctional.

Without a functioning endocrine system, as well as feedback from the afferent neurons and the feedback loops provided by bodily tissue, there would be an almost total absence of emotional experience, and likely pathological development of the brain systems associated with these elements.

My suspicion is that "awareness" was a relatively early development in the animal kingdom, so I suspect the basic hardware for rudimentary awareness would exist. However, since consciousness as such is controlled by circadian rhythms and other biological systems, it's anybody's guess what the substance of such an awareness would be like. Damasio and others suggest that consciousness and awareness is intimately tied to having a body, including all the visceral, proprioceptive, and external senses; awareness might be present, but without the body, it likely wouldn't resemble anything that we would understand as consciousness. (And this is assuming a lot about hidden layers; if the split-brain experiments are any indication, it may make more sense to speak of multiple centers of awareness and consciousness, hypothetically "tied together" to function as a coherent whole. I'm not sure they are truly "tied together" even in a normal human subject, but if a subject is insulated in this fashion, what integrating mechanisms exist would likely be at a severe disadvantage.)

It's a maxim of neuroscience that neurons which fire together, wire together; and neurons that fire apart, wire apart. It's hard to see any of that happening in the isolated brain. And since much of the timing and feedback which the brain depends upon for coordinating both development and regular function is mediated through the body, the blood, and the peripheral nervous system, it's unlikely the brain by itself could regulate itself. (There are naturally occurring cycles in the behavior of neurons and brain tissue, e.g. the Crick hypothesis, but as far as I know, the actual function of these oscillations is still unknown; the brain's likely time keeper is the biological processes of the body.)