How do successive rem periods change as the night progresses?

As the night progresses, the duration of REM (Rapid Eye Movement) sleep periods typically increases with each successive cycle. The first REM period may last only a few minutes, but by the later cycles, REM stages can extend to 20-30 minutes or more. This pattern contributes to the overall restorative effects of sleep, as longer REM periods are associated with enhanced memory consolidation and emotional processing.