Facts To Know!! On average, adults need 7 to 9 hours of sound sleep everyday. Humans are only mammals that willingly delay sleep. Finding it hard to get out of bed is called Dysania. Pain tolerance is reduced due sleep deprivation. Unnatural movement during sleep are known as Parasomnia Hypnic Jerks is a feeling of falling when half sleep and jerking awake. Sleep Disorders Watch short video introduction on what Sleep Disorders looks like.