How do a few pounds of gray goo in our skulls create our conscious experience—the blue of the sky, the tweet of the birds? Few questions are so profound and important—or so hard. We are still very far from an answer. But we are learning more about what scientists call "the neural correlates of consciousness," the brain states that accompany particular kinds of conscious experience.

Most of these studies look at the sort of conscious experiences that people have in standard FMRI brain-scan experiments or that academics...