There a four stages of sleep: stages 1, 2, 3, and REM sleep. REM sleep makes up about 25% of your sleep cycle and occurs about 80 minutes after you fall asleep. But since sleep cycles repeat, you have the REM stage several times.
Stage 1: Your eyes are closed, but it's easy to wake you up. This phase lasts about ten minutes. Stage 2: You are in light sleep, your heart rate slows, and your body temperature drops. This means your body is getting ready for deep sleep. Stages 3: It's harder to rouse you during this stage, and if someone woke you up, you would feel disoriented for a few minutes. During this part your body repairs itself.
REM sleep happens 90 minutes after you fall asleep. The first period of REM typically lasts 5-15 minutes. Each REM stage gets longer and longer. Your heart rate and breathing quickens. Intense dreams happen during REM sleep because your brain is more active.
Neurotransmitters are chemicals that are messengers between the brain and organs. Without them you couldn't breath, digest, and your heart couldn't beat. They effect the whole human body, and they play a part in sleeping.
Neurotransmitters help you sleep. The neurotransmitters gamma-aminobutyric acid (GABA) and glycine make REM sleep paralysis happen by “turning off” the cells in the brain that allow muscles to be active and move. This makes it so that you don't move around during REM sleep.
Our emotions play a part in how our dreams turn out. But how do we feel emotions during sleep? Our brain is almost wide awake when we enter REM sleep which allows our emotions to kind of drift around and influence our dreams.
As an example, let's say that Joe is stressed out by school or a test that is coming up. That night he has a higher chance of having a dream where he is stressed out. Joe might have a dream of failing the test, or he might have a dream about a different situation, but he is still stressed out on this situation.
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