寫雲
Why does your body suddenly 'jerk' when you're about to fall asleep?
It's a neural misjudgment where your brain can't distinguish between 'falling asleep' and 'dying suddenly'! This phenomenon is medically known as a 'Hypnic Jerk'. As you transition from wakefulness to sleep, your heart rate slows, breathing becomes more relaxed, and muscles loosen, with the nervous system gradually handing over control to the sleep-dominant regions. However, if you're in a state of excessive fatigue, high stress, or have consumed too much caffeine, a 'signal error' can occur in the motor nerve area of the cerebral cortex. At this point, the brain mistakenly interprets this muscle relaxation and slowing heart rate as a danger signal that 'the body is losing vital signs or falling from a height'! To save you, the brain instantly issues a strong motor command, causing muscles to contract explosively and 'jerk you awake' to confirm safety!
2026.10.15 PM 1:58 · View Count 104
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Lv.73
洋娃娃
Let's check out some new knowledge.
Lv.78
空織鸇
I always do this when I fall asleep in class 😭, and I even got a new nickname, they call me Nukedan Ge (because one time I was sleeping at noon, the desks and chairs were the old wooden kind everyone had seen, and my drawers were empty. When I woke up, I almost flipped the table over. I knew everyone else was awake, but I pretended to still be asleep. After I got up, someone asked me about it, it was super embarrassing 😭😭😭)
Lv.53
靜兒
I see
Lv.78
自由女神2
Learned something new.
Lv.84
災星陳
Thanks for sharing, very useful!
Lv.37
窗戶上卡了一隻貓
I think I'll awaken if I pull just once.
Lv.84
sange
Your mind is too tense and hasn't relaxed yet, which leads to this kind of situation.
Lv.81
閃閃
Thanks for sharing, learned something new!
Lv.88
軟綿綿
I woke up just wanting one more pull, but if I'd done two more, I wouldn't have slept that day. It's a total vicious cycle > <
Lv.49
萬年渣渣
So, did you almost die and then save yourself? 😂
Lv.99
陳阿欣
Amazing! Can you write about sleep paralysis? I used to have severe sleep paralysis.
Lv.6
帥氣瑋
Serious
Lv.77
暗夜幽香
I thought it was because I was 'startled' that I was like this. Turns out I misunderstood.
Lv.78
goodluck
Thanks for the useful info!
Lv.66
安清
Me: 😴😴😴 Brain: Wake up!
Lv.16
Lextry
You have a lot of experience, that's true.
Lv.70
曹朋
I see, thanks for sharing the trivia!
Lv.36
月初Lista
That pull really startled me awake.
Lv.88
derosa
I see, if it's just twitching then it's fine, but if it's twitching and making noise during class, that would be quite embarrassing...
Lv.89
Christine622
I see! I sometimes scare myself awake! Do you guys ever do that?