Why can't you move when you wake up at night?

The short answer

It's not a ghost: in dream sleep your brain switches your arms and legs off, and sometimes you wake up before they switch back on. Scientists think the dream spills into your room.

The twist: your body switches off like this several times a night.

The story, line by line

1. Here's what actually happens when you wake up... and CAN'T move.
2. You try to shout... nothing. Only your eyes move... and there's a shadow in the doorway!
3. But it's NOT a ghost.
4. In dream sleep, your brain switches your arms and legs OFF, so you don't act out your dreams.
5. Without it... you'd do THIS!
6. But sometimes your brain wakes up FIRST, while the switch is still off. That's sleep paralysis... and scientists think the dream spills into your room.
7. Seconds or minutes later, the switch flips on... and POOF! Gone.
8. Here's the twist... your body switches off like this several times a night. Sweet dreams...