There are excellent (not flaky) reasons to believe that consciousness does not derive from processes of the brain. There are insurmountable logical problems with that idea. But to cut a long story short the alternative picture, popularly proposed, is that the consciousness is the 'first cause' to the material world. The idea being, that the consciousness(es) creates the material world as a kind of collective dream. Hence, the material world a simulation.
This is a speculative hypothesis that may or may not be right. It looks absurd on the immediate face of it, yet it's fair to say that it's no more radical than the idea of anything existing at all - and existence, from a strictly logical outlook, is self-evident yet mad...
The fact of existence suggests that something can give birth to itself out of nothing, which is more magic than magic. Magic at least respects some kind of [incomprehensible] cause-to-effect. Existence suggests an effect with no cause at all. Yet here it is - and here we are. That's "mad".
The popular assertion from people who assert that consciousness comes first and is the be-all, is that the brain does not create consciousness but filters it. Filters? This doesn't make good sense to me. I think what is more likely, is that the brain focuses consciousness. Think of it like this...
When you're watching a movie, you may be so absorbed in the screen that you forget where you are - you forget the room you are in. When you finish the movie, you then feel like you've "woken up" to the room you were always in. The movie had focused your conscious attention - not filtered it.
I suggest that this is how the brain/mind works. The consciousness is based in the field behind the brain (to be clear, I'm talking about the same field responsible for magnetic forces, and [as best as we can know] the same field responsible for matter as we know it. Matter is a vibration within the field). So, for a given lifetime, we log on to our brain just like we log on to a TV to watch a movie...
The brain is, in effect, a read-write terminal that read-writes the outside material world (and builds internal models of the outside world, that then allow us to run simulations. We call it thinking) and also read-writes from the consciousness itself. So basically, the brain is an extremely sophisticated 2-way bio-electric eBook. But ultimately only a book.
It's interesting to note, that people who have near death experiences (NDE's) consistently report that when they die (temporarily) it's like waking up and 'going home' - and from their experiences they say that this life (this material life) is the comparative dream. It's like my example of 'waking up' from a movie you were absorbed in. NDE people also report having a "wider consciousness" and being far more capable of clear thought and lucid perception; again, just like waking up from a prior zone, immersed in your TV.
NDE people also suggest that incarnating (focusing) to a material brain leads to deep amnesia. This relates to the greater reality that we're supposedly more truly based in. Again, like when you're absorbed into a narrow focus on something, you can't remember outside things because your mind is zoned-out of all memory not associated with your current brain activity, that naturally holds you captive for the time.
To me, this is a more plausible model than claiming material is not really there and consciousness is primary. Though that might ultimately be the case, we can't know. For the sake of hypothesis though, I think it's better to see the consciousness as based within the field, and focused to the brain for a given lifetime. The model is robust and explains a lot, including much psychic phenomena.
A final note. I have not explained the consciousness itself. That's because I can't - no one can. Though real, it's totally incomprehensible in itself. We can only observe its relationship to the brain - not understand what it actually is.
