Why Your Body Jerks When Falling Asleep - #4

A Spot of Science: Why Your Body Jerks When Falling Asleep - #4

Why does your body jerk when you're just about to fall asleep? And the beetle that shoots it's enemies with acid from its butt. How does it not blow its own legs off? Gus Sorola challenges Chris Demarais and evolutionary biologist Sally Le Page with some of the quirkiest science questions submitted by viewers. Brought to you by Blue Apron ( http://cook.ba/1pkkO63)

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Comments (62)

  • Septimundo FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    3 months ago

    I love how thrilled Gus always seems to be when doing the sponsor bit.

  • Jgulezian FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    4 months ago

    "Over 40 species of bombardier beetles are found in the United States." -National Wildlife Federation

    https://www.nwf.org/Wildlife/Wildlife-Library/Invertebrates/Bombardier-Beetles.aspx

  • PoisedTick0 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    4 months ago

    I think I may have experienced the body-jerks-before-sleeping; But I was falling asleep in middle school science class (not a joke, but yes coincidental) and my hand had held the side of my head - and I just kept drooping my head before waking, then relaxing again - seeing the entire class for a microsecond before my eyes closed and the cycle repeated - It was very weird, like pulsing your consciousness on/off. 

  • StevenBelang FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Soren81648

    4 months ago

    I guess it is where the term 'falling asleep' comes from.

  • gerbosphere FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I like how the loading circle on the video player fits perfectly inside the O.

  • gerbosphere FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    So that beetle diagram was a dick, right?  That was totally a dick.

  • JCLegoMan FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Too poor for double gold

    5 months ago

    Sally's face when Chris starts talking about his "theories"

  • m_vivan FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Huh now I finally understand why I suddenly startle awake every few months after a half dream about falling downstairs or tripping. That actually makes a lot of sense, thanks Sally!

  • Zher0 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    lol, that beetle graphic...

  • dragonelf68 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    It's so cute when chris is answering and he looks over at sally for confidence and confirmation

    • dragonelf68 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      nvm because THE AUDIO KEEPS GOING UP AND DOWN WHEN HE DOES IT

  • JohnVuojo FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold The Wanderer

    5 months ago

    I've literally never had that happen. I just go to sleep.

  • MartyGras2

    5 months ago

    Love Sally :)

  • SachiiSez FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Good-Natured Realist

    5 months ago

    "All the cool stuff lives in Australia." - Sally

    Hells. Yes. ^_^

    Laughter and Sunshine!

  • Buddy_Leroy FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I love this show. I wish it was longer! I can never get enough.

  • SC101 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I once experienced the jerking-awake-while-falling-asleep thing in the middle of a maths class.  Totally wasn't embarrassing or anything.

  • carltannler FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold HotCarl

    5 months ago

    Thank you Sally for correcting Chris on the Hypothesis vs Theory thing.  That is my biggest pet peeve is when people mix up theories and hypothesis.  I think the culprit is string theory, mainly because it's mostly still a hypothesis and only parts have hard evidence to support parts of it.  People see string theory and think that evolution and gravity are all lumped into the same category when that is completely not the case.  Both evolution and gravity, as well as the big bang and dark matter now are all theories and string theory is still more of a hypothesis.

    • jacoblambda FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      also when people refer to theories as laws. i.e. "law of gravity"

  • murph048

    5 months ago

    Was that bear in the beginning the same bear from the Father's Day Theater Mode episode?

    • Gozroth FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      It is!

  • mfa

    5 months ago

    I understand that she doesn't live in the US, so they have to record a lot of episodes back to back. From a production standpoint, I just wish they had them change clothes between episodes. I know it would be hard for her to change clothes because she doesn't live here, but she has worn two different shirts... same with Gus, but Chris has worn the same outfit every episode. I know this is a stupid complaint, but when Chris is in the thumbnail wearing the same shirt I always think its an old episode. 

    • ShortayRTB FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      Well 1. She does change her top, and 2. The episodes are numbered in the titles? So I don't see why this is such a big deal?

    • Chris FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      They wanted me to change shirts but I liked that one. I even brought it back to film the next day.

  • devilito666 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Please have Sally Le Page at RTX london 2017

    • Queeblo FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Queeblo McQueebloface

      5 months ago

      I read this in her voice.

  • GrateScot FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Really enjoying the rapport that Gus, Chris and Sally have begun forming as the series develops. Very entertaining to watch, as well as informative. Keep 'em coming!

  • Kavemanbill FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Hypothetically it would be possible to cause a Hypnic jerk with anaesthetic but it would most likely end up happening based on the persons own reflexes and metabolism versus how quickly the anaesthetic would relax the muscles. The idea being that if the anaesthetic is still in the persons system when the signal is sent to the muscles the anaesthetic would, essentially, disrupt the signal and keep the muscles from responding in a hypnic jerk, another issue would be if the anaesthetic doesn't relax the muscles to the point that a hypnic jerk is possible before the anaesthetic is metabolized and, therefore, a hypnic jerk would not occur and the muscles would act normally. But if your muscles hit the hypnic jerk point at the same time as the anaesthetic is fully metabolized, your body would be at the perfect point for a hypnic jerk to occur.


    But that's just a hypothesis.

  • Lt-Waffles FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    can we all agree that Sally is one of the most awesome and amazing people RT has ever brought into our lives?

  • dunlaw FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I've had that falling feeling before, but I've never jerked upright after feeling it. I always thought it was so relaxing as I slipped away on a flying mattress. It was fucking weird, but peaceful.

    • corbandioxide FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      I've had that before too, but I think what they're talking about is something different. Usually I get it when I'm just about to fall asleep and I sort of "half-dream" about falling down some stairs or from a building or something, and I jerk awake because I'm about to land.

  • Foxpox FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    love this series and a big fan of Sally! Think the addition of Chris has been fantastic as well and (surprisingly) find myself agreeing and sharing his thoughts and ideas of why things are the way they are... my only problem is that whenever Chris is giving a shot at trying to answer, even some that Gus is agreeing to, Sally seems so incredibly rude with the remarks she makes. Idk, I feel like she could be even just a LITTLE bit more kind. Maybe I'm alone in this. 

    • hoffm83n FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      his thought processes usually have some reasoning behind them, i wish there was a little more discussion of where his logic is sound but the science doesn't back it up. his idea of a hypnic jerk being a double check should have been connected to anxiety and different sleep problems. 

  • JsseNlsn FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    In theory (or hypothesis), the jerk could not occur with artificial sedative since the muscles are so relaxed that the brain cannot jerk the muscles?

  • Fenrir_Shade FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I wonder how the Hypnic Jerk feels to someone in weightless gravity (such as on the ISS) and how often that sensation takes place? I understand that they sleep in individual cabins, but your body is quite literally weightless. So I'd assume that the sensation is exasperated and much more commonplace.

    • LTFartsworthy FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      Maybe? I'd assume with the constant feeling of weightlessness you wouldn't feel it because its a constant sensation? Like Sally said the feeling was due to your body reaching that stage of relaxation. Would it have the same reaction if you fell asleep while already feeling the weightlessness sensation?

  • readalot FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I can't believe i haven't watched this before. It is FANTASTIC.

  • AH_Justicar FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Pirate Captain

    5 months ago

    How does Sally know so much about so many different things? Her intelligence is beyond my comprehension...I guess that's why I work minimum wage jobs XD

    • bbrodriguez

      5 months ago

      I'm guessing she researches the topics in advance when they receive the questions. Hence why she knows so much about how the beetle's acid works but not where they live

  • Icky427 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Icky

    5 months ago

    also, Gus, you have the right shirt on for a pun. barbara

  • Icky427 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Icky

    5 months ago

    chris: this is more psudoschience

    sally: as opposed to the rest of that?

    BOOM! HEADSHOT! +1 ZING to sally

  • krae98 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    the fucking brown bear 

  • BeavyMcBeaverson FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Good times to be had.

    5 months ago

    I've always thought that the hypnic jerk was caused by you being so calm that your heart rate got so low that your brain thought you were dying, and due to that it caused the jerk to try and revive. 

  • ChrisVolkoff FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Chris

    5 months ago

    For some reason it's weird seeing Gus read the ad from a prompter instead of his iPad, like in the RT podcast

  • MikeSG87 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    So does Sally live in Austin now, did they film all these in a short period, or are they gonna go back to the video call style??

    • EliBurry1000 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      They shoot them in batches 

  • RavenSugara FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Streamer/Fic Writer

    5 months ago

    if Sally wasn't one of my heroes before, she put it over the top with the that's what she said. Expertly done.

  • rybread8 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    was that the bear from the Fathers Day Theater Mode in that photoshop?

  • MiniHoss FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Your brain does not 'literally' say those things, learn how to use the word.

  • bigonrock FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    While Sally was describing the Beatles pulses the diagram looked a penis ejaculating lmao

    • CptObvious1994 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Thanks, Captain Obvious

      5 months ago

      "Beatles"

      I didn't realize John Lennon could spray boiling hot acid.

    • JeffHead FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold JeffHead

      5 months ago

      Yep, can't stop laughing at the jizzing beetle ass cock

  • thealexalcala FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Blue Apron code doesn't work, just FYI.

  • Darkash150 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Oh Cool they used my question!

  • Bendaman98 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    Sally cringes whenever Chris talks.

  • Mightguy99 Joon Bug

    5 months ago

    she is actually partially wrong, as there are a couple of hypothesis as to why we get hypnagogic jerks. which the falling one is still considered the weakest of them.

    • MVshogun FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      what are the other theories then please?

    • TomBenstead FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

      5 months ago

      I know I have heard one saying that it is a leftover evolutionary trait from when our ancestors lived in trees. If you are going to sleep in a tree you have to cling on to it, so as our bodies start to relax the brain thinks it is going to fall out of the tree and tenses up. Although that could just be an expanded version of the same thing Sally was talking about.

    • Mightguy99 Joon Bug

      5 months ago

      a very good video on the subject

  • creativeLunatic FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold always tired

    5 months ago

    someone please fix chris's mic, he's been struggling with it for a while now

  • AlysonMc FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    5 months ago

    I love this show so much, because apart from the fascinating science, it's basically a show designed to make fun of Chris, and I can support that.

  • Thawds FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Discord Bois

    5 months ago

    Those beetles are absolutely incredible! 

  • Lloyd_Edgar FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold Lloyd Edgar

    5 months ago

    the hype train is embarking, please have your ticket ready *TOOOT TOOOOOT*