Studies in animals have shown that the equivalent area drives the basic instinct to satisfy thirst, hunger, warmth and sexual desire. Because if the ventromedial frontal lobes are damaged, dreaming can't occur, Dr. Solms concludes that the lobes are key to dream formation. The dreams about Tetris don't negate the idea that dreams are driven by instinctual urges, he argues. It may be, he said, that dreaming about the game is a manifestation of a basic, competitive urge. There are limits, Dr. Solms said, to what biologists can say about Freud's theory that dreams have hidden meanings.
Psychoanalysts agree, saying the only evidence they have comes from sessions with patients.
Just because Freud's theories aren't fully testable by science, Dr. Nersessian said, doesn't mean they're not worth thinking about. But his ideas are 100 years old, and by bashing him you don't learn anything. If you study him, it opens up new doors to learn new things.