W hat are dreams? For centuries, dreaminghashadculturesaroundthe world grasping for an explanation. The Greeks believed dreams were both a prediction of the future and visits from loved ones lost. The Egyptians suggested dreams were simply a different form of seeing, even training dreamers to help plan battles and provide insight on state decisions.SigmundFreud,famedneurologist and psychologist, suggested dreams are a window to our unconsciousness. But there’s more to dreams than just theories, there’s science. Technological advancements and new research have allowed scientists to examine and build on these theories. Check out these five fun scientific facts about dreams. ONEREMsleepmaytriggerdreaming The brain moves through five stages during sleep, including rapid eye movement (REM) sleep. In this stage, the eyes move rapidly, and breathing can become fast or irregular. It’s also in this stage that dreaming is most likely to occur. REM sleep is typically entered within 90 minutes of falling asleep and occurs multiple times as the sleep cycle repeats through the night. TWODreamingoccursthroughoutthesleepcycle During transitional stages, such as waking up (hypnopompic) or falling asleep (hypnogogic), dreaming experiences may occur. These stages are also known as non- REM sleep. However, while dreaming is possible throughout all stages of the sleep process, you’re more likely to remember REM dreams than those coming to life in its non-REM counterparts. THREEDreamscanbeagreatteacher You’ve heard the term, “Let me sleep on it.” Can you believe your brain can teach itself while you’re sleeping? This is possible through a process Harvard neuroscience professor Robert Stickgold calls “off-line memory reprocessing.” The process found sleep, and dreams, play an important role in memory and learning, both before and after a task or behavior is learned. This is because anytime a new memory is made, that information transfers through different areas of the brain to stick around for a while, and those memory- saving patterns correspond with the patterns of brain activity during sleep. 14