Ever start to fall asleep — and suddenly JOLT awake?It's called a "sleep start," or hypnic jerk. And new research links frequent episodes to anxiety and poor sleep.Researchers surveyed nearly 200 adults and found those experiencing jolts at least once a week reported worse sleep quality, more insomnia symptoms, and higher levels of anxiety and depression.Participants reported more episodes during periods of emotional stress.Those with more negative thoughts about sleep also tended to startle awake more often.The lead author says, “Sleep starts are much more than a simple muscle twitch when falling asleep.”Participants described sensations of falling, racing hearts, flashes of light, even loud bangs — sometimes accompanied by fear or panic.Most drifted back to sleep quickly, but some experienced real distress.Researchers say it's unclear whether anxiety and pressure to fall asleep contribute to the jolts — or vice versa.Next, they want to find out whether reducing worry about sleep could make these episodes less distressing.Source: PLOS Mental HealthAuthor Affiliations: Paris-Lodron-University .Sign up for our weekly HealthDay newsletter