Yes, they can – you can make a lab environment within the normal range for human fetal development, therefore causing the brains to develop consciousness in the same way, for the same reasons. Therefore, there exists at least one scenario in which this can occur.
There's not much difference between the way that brain tissue develops in fetal development and in current lab environments.
> There's not much difference between the way that brain tissue develops in fetal development and in current lab environments.
But wouldn't the sensory input be completely missing? A fetus at least has some of these inputs as the sensory organs are developing, which is part of getting sentience. A brain in a vat has no equivalent so it would lack a lot of additional input that usually goes into forming a human consciousness/sentience.
> A fetus at least has some of these inputs as the sensory organs are developing,
Deaf-blind individuals still exhibit consciousness. There are people who can't smell, or feel touch, or temperature, or pain. How many senses do you have to remove before consciousness goes away?
If consciousness can exist with the absence of senses (e.g. if you were cut off from your senses for five minutes), then who's to say it can't develop without them? We don't know that consciousness requires sensory input; is it safe to assume that?
Consciousness isn't about external sensory perception (at least in my version of the word ;), it's about internal perception. For example, flexing a muscle and correlating the different skin/motion/stress sensors as feedback to the initial motion. Flexing a different muscle and experiencing the tactile sensations from your fingers. Making sense of the myriad of nervous system signals that travel through the spine at any given second.
There's a lot of different inputs and outputs to organize and understand before the brain can even begin to make sense of the world outside the body. In that sense, yes, the brain needs sensory inputs to assert itself, but our traditional "five senses" are but a small subset of the sensory input the brain receives and must process.
I don't know how much we know about the brain but I think inputs could be electrically simulated. Regardless, I'm not so sure "consciousness" depends on inputs as much. The assumption is its consciousness would be similar to our own but an organism that was created in a lab might feel entirely different such that we can't really compare what it would be like to just take our brain and put it in a jar.
I believe there is some phenomena related to the way people born blind visualize or think about things, but I only vaguely remember reading about such things.
If I lost all “bodily” sensory input and somehow kept my mind, I believe that I would still sense my emotions. I don’t think the basic experience of existing requires a body beyond the “brain” itself.
There's not much difference between the way that brain tissue develops in fetal development and in current lab environments.