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have you ever been drifting off to sleep in your bed all quiet at night and
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suddenly feels like you're falling in your whole body twitches what is that
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well that's a jerk, a hypnic jerk to be precise, a hypnic jerk sometimes called a sleep start is
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the scientific term for what happens when you jump in your sleep there the
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involuntary muscle twitches that happened in your arms legs or even your
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entire body as you drift off to dreamland, most people get them roughly
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70% of the population jumps in their sleep, but why do they happen
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there are two main theories based on neural science and evolution most common
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explanation is that as you fall asleep there are two different systems your
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brain that are basically battling each other. System number one, a network of
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nerve cells called the reticular activating system is just below your
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cerebral cortex the big wrinkly part of your brain. when this system is in full
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force you feel alert, it essentially helps keep you awake. system number two
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call the ventrolateral preoptic nucleus or VLP0 for short is located near the
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optic nerve and influences your sleep cycle, the VLP0 sometimes referred
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to as the sleeps switch, as you fall asleep each night or during nap time
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the VLP0 system begins to take control from the reticular activating
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system during this hand off from one system to another the alert part of your
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brain can still sometimes stimulate your muscles causing twitches, these hypnic jerks are
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last-ditch attempts by the reticular activating system to maintain control of
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your body as you more or less choose to sleep, system number one usually
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seized control the system number two the VLP0 and the hypnic jerks eventually
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stopped, so these jerks are thought to be the result of a sleeping waking war
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happening in your body each time you try to get some shut-eye, another less common
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theory for what causes hypnic jerks involve our primate ancestors. some scientists think
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that the ancient primate brain associated relaxation or the beginning
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stages of sleep with falling out of a tree, hypnic jerks were a way of waking the
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primate up quickly so they could take action and possibly break their fall.
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so these muscular twitches might have stayed with us as we evolved over the years.
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whatever causes hypnic jerks they're nothing to worry about according
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to most experts but if you don't love getting jolted awake feeling like you're
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plummeting near-death there are some steps you can take to limit how many
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sleep start to experience things like high caffeine consumption, working out in the evening hours,
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high stress levels and lack of sleep can cause more frequent
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and more intense hypnic jerks, so cutting back on the coffee, getting your workout
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done in the morning and managing your stress levels and sleeping patterns
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might result in fewer hypnic jerks, but like I said they're not dangerous
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so if they don't bother you, no need to ditch your afternoon latte, there're bigger jerks
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out there to battle after all. Thanks to all of our patrons on patreon for not being jerks
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