Michael W. Clune at Harper’s Magazine:
Despite some intriguing speculation, scientists haven’t yet come up with a clear, satisfying answer to the question of why we dream. Part of the reason is doubtless because, as any time spent studying neuroscience will show you, our knowledge of the brain is in its infancy. And part of it is due to the special limitations of dream research. Animal studies—sometimes referred to as the gold standard of neuroscientific research (think of the things one can do to rat brains that one can’t do to humans)—are of no help here. Like many pet owners, I believe that my dog dreams. But when I see her lying on the couch, muttering and growling with her eyes moving behind closed lids, I can’t wake her and ask her what she saw. When I spoke about the state of the field with the dream researcher Erin Wamsley, she described a kind of disappointment, a sense that the breakthrough insights into the nature of dreaming that seemed imminent a decade or two ago haven’t materialized.
more here.