 A particular problem for any theory on the function of dreaming is to explain why a majority of dreams are forgotten and how dreams can fulfill their putative function independently of recall. Crick and Mitchinson (1983) famously proposed that REM sleep “erases” or deletes surplus information and unnecessary memories, which would suggest that enhanced dream recall is counterproductive. Another problem is that dreaming can be lost selectively and independently of other cognitive deficits (Solms 1997, 2000).