Which stage of sleep is characterized by dreaming?

The stage of sleep characterized by dreaming is REM, which stands for Rapid Eye Movement. During REM sleep, the brain is highly active, and this is when most vivid dreaming occurs. This stage of sleep is important for cognitive functions such as learning, memory consolidation, and emotional regulation. Physiologically, the body's muscles are temporarily paralyzed, which prevents individuals from acting out their dreams.

This distinct stage occurs cyclically throughout sleep periods, typically starting about 90 minutes after falling asleep and recurring several times throughout the night. REM sleep is notably different from non-REM sleep stages, which include lighter sleep (N1), moderate sleep (N2), and deep sleep (N3).