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  • have you ever been drifting off to sleep in your bed all quiet at night and

  • suddenly feels like you're falling in your whole body twitches what is that

  • well that's a jerk, a hypnic jerk to be precise, a hypnic jerk sometimes called a sleep start is

  • the scientific term for what happens when you jump in your sleep there the

  • involuntary muscle twitches that happened in your arms legs or even your

  • entire body as you drift off to dreamland, most people get them roughly

  • 70% of the population jumps in their sleep, but why do they happen

  • there are two main theories based on neural science and evolution most common

  • explanation is that as you fall asleep there are two different systems your

  • brain that are basically battling each other. System number one, a network of

  • nerve cells called the reticular activating system is just below your

  • cerebral cortex the big wrinkly part of your brain. when this system is in full

  • force you feel alert, it essentially helps keep you awake. system number two

  • call the ventrolateral preoptic nucleus or VLP0 for short is located near the

  • optic nerve and influences your sleep cycle, the VLP0 sometimes referred

  • to as the sleeps switch, as you fall asleep each night or during nap time

  • the VLP0 system begins to take control from the reticular activating

  • system during this hand off from one system to another the alert part of your

  • brain can still sometimes stimulate your muscles causing twitches, these hypnic jerks are

  • last-ditch attempts by the reticular activating system to maintain control of

  • your body as you more or less choose to sleep, system number one usually

  • seized control the system number two the VLP0 and the hypnic jerks eventually

  • stopped, so these jerks are thought to be the result of a sleeping waking war

  • happening in your body each time you try to get some shut-eye, another less common

  • theory for what causes hypnic jerks involve our primate ancestors. some scientists think

  • that the ancient primate brain associated relaxation or the beginning

  • stages of sleep with falling out of a tree, hypnic jerks were a way of waking the

  • primate up quickly so they could take action and possibly break their fall.

  • so these muscular twitches might have stayed with us as we evolved over the years.

  • whatever causes hypnic jerks they're nothing to worry about according

  • to most experts but if you don't love getting jolted awake feeling like you're

  • plummeting near-death there are some steps you can take to limit how many

  • sleep start to experience things like high caffeine consumption, working out in the evening hours,

  • high stress levels and lack of sleep can cause more frequent

  • and more intense hypnic jerks, so cutting back on the coffee, getting your workout

  • done in the morning and managing your stress levels and sleeping patterns

  • might result in fewer hypnic jerks, but like I said they're not dangerous

  • so if they don't bother you, no need to ditch your afternoon latte, there're bigger jerks

  • out there to battle after all. Thanks to all of our patrons on patreon for not being jerks

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have you ever been drifting off to sleep in your bed all quiet at night and

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B2 US sleep system primate jerk brain ditch

Why Do We Jump in Our Sleep?

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    Joseph Yap posted on 2016/07/07
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