Sometimes when we are about to fall asleep after staring at the ceiling for some minutes, our body suddenly jerks right up because we felt like we were about falling off a cliff or about to be hit by something. Nobody knows the actual cause of this but to me it’s fascinating, because it gives me the sense that I going to rest well for the night.
Here are the reasons you suddenly jerk up back while falling asleep
The Body Jerk
Majority of the time you jump because you feel like you’re falling, being hit or were scared by something you saw in your sleep. Some people feel embarrassed while some are startled by it, but it’s not bad after all.
Hypnic Jerk
Physically, hypnic jerks resemble the “jump” experienced by a person when startled, sometimes accompanied by a falling sensation. Hypnic jerks are associated with a rapid heartbeat, quickened breathing, sweat, and sometimes “a peculiar sensory feeling of ‘shock’ or ‘falling into the void.
Defense Mechanism
Doctors believe this is your body reacting to the first stage of sleep, which is when your breathing and heart rate slows. Your body begins to think your organs are failing and tries to wake you up with a jolt! Some say this happens when extremely exhausted.
see more:http://www.nowayobloggers.com/blog/lifes-ultimate/here-is-why-you-suddenly-jump-up-while-falling-asleep-see-more-picture-below