Book: Sleep critical to learning, memory

COLUMBUS, Ohio, Nov. 26 (UPI) -- Improving sleep can enhance memory and intelligence, a U.S. author says in his book "REM Illumination Memory Consolidation."

Dr. Timothy J. Walter, a sleep medicine physician and neurologist, integrates different research findings on sleep and memory and explains how the brain uses emotion throughout the day to decide which memories are worth keeping. While people asleep, the same emotion in a dream may aid in the burning of the memory into the matrix of pre-existing memories, Walter said.

Walter says the discovery of rapid eye movement, or REM, sleep windows -- typically 20 percent to 25 percent of total sleep lasting about 90 to 120 minutes a night -- following learning helps to permanently store memories.

If these REM sleep opportunities are missed, either through sleep deprivation or a sleep disorder such as obstructive sleep apnea, the opportunity to store specific memories may be lost forever, Walter said in a statement. Getting adequate sleep may improve learning and memory, he said.

Walter is co-medical director of Capitol Sleep Medicine Sleep Diagnostic Center in Grove City, Ohio.