3. Stages 3 and 4: Non-rapid eye moment
Slow wave sleep is also known as SWS. This state occurs during the third and fourth stages of sleep. They are usually combined since there are many common patterns. Specialists claim that the deepest part of the entire sleep cycle occurs during this period. A person who is suddenly woken during this phase feels groggy. Slow wave sleep is very important since this is when your body cells restore and rejuvenate. Your system releases growth hormones that help heal tissues and muscles. The blood actively delivers nutrients and oxygen to all body parts and organs. Bedwetting and sleep walking occur during these two stages, too.

4. Stage 5: Rapid eye moment
The final stage of the cycle differs from the other four. During this stage a person experiences rapid eye moment sleep. It takes up approximately 20% of sleep. Your brain I now ready to be revitalized. Scientists describe it as the most important stage since without this phase you cannot feel fully prepared for daytime functioning.