Koch spent decades at Caltech hunting the neural correlates of consciousness with Francis Crick, and this is his case for integrated information theory — the idea that consciousness is a measure of how much a system’s parts inform each other, and that it can in principle be quantified. Which means, on his account, that a cerebellum with more neurons than the cortex has almost none of it, that some animals have plenty, and that a digital simulation of a brain would have essentially none no matter how good the simulation. He also writes about a psychedelic experience and a near-death moment, which most neuroscientists wouldn’t.
Then I Am Myself the World