The human brain insists it has consciousness, with all the phenomenological mystery, because it constructs information to that effect. The brain is captive to the information it contains. It knows nothing else. This is why a delusional person can say with such confidence, “I’m a kangaroo rat. I know it’s true because, well, it’s true.” The consciousness we describe is non-physical, confusing, irreducible, and unexplainable, because that packet of information in the brain is incoherent. It’s a quick sketch.
What’s it a sketch of? The brain processes information. It focuses its processing resources on this or that chunk of data. That’s the complex, mechanistic act of a massive computer. The brain also describes this act to itself. That description, shaped by millions of years of evolution, weird and quirky and stripped of details, depicts a “me” and a state of subjective consciousness.
This is why we can’t explain how the brain produces consciousness. It’s like explaining how white light gets purified of all colors. The answer is, it doesn’t. Let me be as clear as possible: Consciousness doesn’t happen. It’s a mistaken construct.