This is an interesting thought; but your assumption that the brain would just "create its own little world" is unfounded. Like other animals, we are born with certain instincts. It's not been definitively proven that the brain is some sort of perfect blank slate.
While I'm not denying that human brains have been shown to hallucinate under sensory deprivation, there's no way to say whether or not a lab grown brain would experience discomfort because of its lack of input, or whether it would even dream up a coherent reality for itself at all. There's simply no way to test this.
While I'm not denying that human brains have been shown to hallucinate under sensory deprivation, there's no way to say whether or not a lab grown brain would experience discomfort because of its lack of input, or whether it would even dream up a coherent reality for itself at all. There's simply no way to test this.