The purpose of REM sleep is constantly being questioned. Some studies indicate a connection between REM sleep and memory processing. People who are deprived of REM sleep and dreaming are less likely to recall complex information learned earlier in the day than are people who were not deprived of REM sleep. REM-deprived people also report having difficulty concentrate when they awaken. These findings have led researchers to speculate that REM sleep---and perhaps dreaming---facilitates the storage of memories as well as mental strategies. At the same time, REM appears to help us process recent emotional experience and to “discard” information that is trivial or less important to us. Other research shows no relationship between time spent in REM sleep and memory problems. The exact connection between REM sleep and memory continues to be investigated.