~Falling~ Asleep

We've all had the weird experience when trying to fall asleep where you suddenly feel like you're falling, you twitch and have to start trying to sleep again. But have you ever wondered what it was, or why it happens?
This phenomenon is called a hypnagogic myoclonic twitch, or a hypnic jerk. According to the Mayo clinic, a nonprofit medical research group, around 70% of people experience this. From what I've read, I haven't found any definite reason for the twitch, but instead a few theories. One theory that resonates most with my biology background is the one in which your body, in its attempt to relax and prepare for rest, begins to relax its muscles. When these muscles go slack, your brain misinterprets it as a signal that you're falling. The accompanying twitch is your brain trying to compensate from you 'falling'. It's almost like a knee-jerk reaction. It's nice to know that my brain looks out for me. :3

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