Ernest Hartmann: the image that holds the feeling

Hartmann, a psychiatrist at Tufts University in Boston, spent decades studying dreams and nightmares. His theory suggests that dreaming makes connections more loosely than waking thought, and that emotion guides which connections get made.

He paid most attention to the central image: the most striking picture in a dream. In his view, it tends to picture the dreamer's strongest feeling. His best-known example is the tidal wave that sweeps everything away, a common dream after trauma, which pictures a feeling of being overwhelmed rather than anything to do with the sea.