“Neuroscientists do know that consciousness does not reside in any one part of the brain — there is no region where all information is aggregated together — but they don’t know much more than that…. Anesthesia… is a great example of whyscientists have to think about consciousness. It’s not enough, he said, just to assume your patient is unconscious because she doesn’t respond to pain.

“Philosophers are fond of pointing out that, for all you know, you’re surrounded by people who appear to be fully conscious but who experience none of it subjectively. (They frequently trot out these beings for thought experiments and call them “philosophical zombies.”)”

Philosophical zombies aside, “… [a]ctivity in conscious brains has been shown to loop between sensory areas (the visual cortex in the rear of the brain, for example) and the higher-level parts of the brain associated with processing information (like the temporal lobe, just behind your ears). Mashour and others call this “recurrent processing”: Signals travel from the sensory areas to the processing areas and back again. When somebody is unconscious, the recurrent proc­essing disappears.”

Article here.