Dreaming 'eases painful memories’

Scientists have used scans to shed more light on how the brain deals with the memory of unpleasant or traumatic events during sleep.
The University of California, Berkeley team showed emotional images to volunteers, then scanned them several hours later as they saw them again.
Those allowed to sleep in between showed less activity in the areas of the brain linked to emotion. Instead, the part of the brain linked to rational thought was more active.
The study, published in the journal Current Biology, said it showed the links between dreams and memory.
Most people have to deal with traumatic events at some point in their lives, and, for some, these can produce post-traumatic stress disorder (PTSD), leaving them emotionally disturbed long after the event itself.

Source  - BBC