Less REM Sleep Tied to Greater Risk of Dementia
People who get less rapid eye movement (REM sleep) may have a greater risk of developing dementia, according to a study published in the online issue of Neurology®, the medical journal of the American Academy of Neurology. This is the stage when dreaming occurs.
There are five stages of sleep. Stage one is light. Stage two is when the body begins to prepare for deeper sleep, including stages three and four. Stage five is REM sleep. During this dream stage, the eyes move rapidly and there is increased brain activity as well as higher body temperature, quicker pulse and faster breathing. The first REM stage occurs about an hour to an hour-and-a-half in and then recurs multiple times throughout the night as the cycles repeat.