Each stage of sleep contributes uniquely to memory consolidation:
1. NREM Sleep: Comprising stages 1-3, NREM sleep, especially stage 3 (also known as deep sleep or SWS), is vital for consolidating declarative memories. During SWS, the brain exhibits slow oscillations, which are thought to facilitate the transfer of information from the hippocampus to the neocortex for long-term storage.
2. REM Sleep: This stage is characterized by rapid eye movements and increased brain activity. REM sleep is crucial for consolidating procedural memories, such as skills and tasks, and emotional memories. The brain's limbic system, involved in emotion regulation, is highly active during REM sleep.
