An ostracized brain

[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.)