Why does the human body jerk/shock itself awake sometimes while trying to sleep?

Question

Why does the human body jerk/shock itself awake sometimes while trying to sleep?

In: 2959

Answer 1

“Hypnic jerks or sleep starts are benign myoclonic jerks that usually occur on falling asleep. Various factors like excessive caffeine intake, physical, and emotional stress can increase their frequency.”
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4481805/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4481805/)