An inactive state resembling deep sleep in which certain animals living in cold climates pass the winter. In hibernation, the body temperature is lowered and breathing and heart rates slow down. Hibernation protects the animal from cold and reduces the need for food during the season when food is scarce. Compare estivation.
Does Dreaming Indicate a Good Nightâs Sleep? Dreams are typically indicative of a good nightâs sleep, demonstrating that you have passed through the light sleeping phase (NREM) and entered into a deep sleep (REM).
The REM Sleep Stage. REM sleep is the second type of sleep, often kicking in only after a full cycle of NREM sleep. This is the stage where most dreaming occurs. REM is sometimes called paradoxical sleep because brain scans of people who are in REM show that their brains are very active, despite the fact theyâre fast asleep. However, while your brain is active, only your eyes can move. There are exceptions though.