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It is now 4 stages, not 5!!!! X
Stage 1 typically lasts about 5-10 minutes
Also known as Light Sleep
Stage 2 typically lasts about 20 minutes Stage 2 still has theta waves but they show sleep spindles which show stronger brain activity
About 45% of sleep is spent in this stage – you pass through this stage several times in a night
Stage 3 typically starts 35-45 minutes after falling asleep Stage 4 “technically” no longer exists Stage 3 typically starts 35-45 minutes after falling asleep Stage 3 and 4 used to be split according to the frequency of delta waves – stage 4 used to be when delta waves were more than 50% of the total
Dreaming CAN take place in this stage. This is the stage where PARASOMNIA disorders occur Night terrors, sleep walking, sleep talking, etc Stage 3 and 4 used to be split according to the frequency of delta waves – stage 4 used to be when delta waves were more than 50% of the total
Children and Teens tend to be in this slow wave stage more than adults
About 20-25% of sleep time is spent in REM sleep This stage usually dominates the latter half of the sleep cycle
Paradoxically, these brain waves are similar to when you are awake
The Pons area of the brain is responsible for the paralysis A 2012 study out of the Univ. of Toronto found that two powerful brain chemical systems work together to paralyze skeletal muscles The Pons area of the brain is responsible for the paralysis
The brain areas involved with long-term memory and emotion are highly active during REM sleep (image from Zeology)
If we were not paralyzed, our brain would cause us to act out our dreams. An experiment done on cats where certain nerves were severed caused the cats to stalk invisible prey, run and jump wildly during REM sleep
Websites Used http://www.howsleepworks.com/types_rem.html http://blog.hubspot.com/marketing/science-of-sleep http://blog.withings.com/2015/03/17/the-4-different-stages-of-sleep/ https://www.psychologytoday.com/blog/the-athletes-way/201512/sleep-loss-disrupts-emotional-balance-the-amygdala