ABSTRACT
There is no denying that good things may indeed happen to people during dreams, such as memory reorganisation. What is in question is whether these good things are essential to their physical and mental health or even to the survival of our species. The modern scientific concept of dreaming sleep began with the discovery of rapid-eye-movement (REM) periods which occurred at intervals throughout the night. Volunteers, when woken from REM sleep, frequently reported that they had been dreaming and would often be able to give a vivid account of their dream on request. The early studies of REM sleep showed impressive evidence for a link between it and dreams. Much of this has had to be qualified by later analysis but the basic idea is still valid, the idea that people will often report a dream when woken from a REM episode. Some early investigations seemed to show a link between pictures of the dream and the particular eye-movements observed.
