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what are sleep cycles
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so normal human sleep is characterized
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by regular repeating patterns of
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different kinds of sleep
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and they continually occur throughout
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the night
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we call the repeating patterns asleep
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across the night sleep cycles
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we call the different types of sleep
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that occur within sleep cycles
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sleep stages now i've covered off sleep
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stages in other videos
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so in this video i'm going to talk about
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sleep cycles only
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during a sleep cycle a person will
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typically transition
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through differing amounts of what we
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call
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non-rem or non-rapid eye movement
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and rem or rapid eye movement sleep
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non-rapid eye movement sleep is made up
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of light sleep
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which are stages one and two sleep and
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then also a stage of deep sleep
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which we know is stage three rapid eye
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movement or rem sleep or dream sleep
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is the last stage of sleep of which
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there's a single stage that occurs
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after all the non-rapid eye movement
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sleep
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if you want to understand a bit more
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about all of those different types or
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stages of sleep
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have a look at the videos on sleep
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stages
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now sleep cycles vary in length across
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the night
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the average length of the first non-rem
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rem sleep cycle is about 70 to 100
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minutes
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the average length of the second and
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later sleep cycles is about 90
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to 120 minutes overall though
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across the night the average period of
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the rem
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or nrem rem cycle is about 90 to 110
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minutes
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across the night stage 1 sleep will
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account for around
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2 to 5 of your total sleep time
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stage 2 sleep will account for about 45
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to 55
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of total sleep time deep sleep
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known as slow wave sleep will account
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for around 10 to
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20 of your night
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and rem or rapid eye movement dream
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sleep
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will account for about another 20 to 25
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of sleep in the night for a healthy
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adult