I believe consciousness is a result of processes of the brain, and the brain is a very complex machine. It's hard to say anything too concretely beyond that because I don't really understand how it works. I live as though the brain and my consciousness are in perfect sync, but I'm unsure how true that is.
There are, for example, experiments where it can be shown that decisions are made before we are consciously aware that we have made them. Others show that severing a nerve between the hemispheres of our brain can result in two independent consciousnesses. Who can say where I end and my brain begins?
That's one way of seeing things, and I respect that viewpoint, but I disagree. I primarily view myself as my consciousness; everything else is secondary. How do you know you aren't a brain in a vat?