Of course, most people feel a little out of sorts if rousted from deep sleep. But sleep drunkenness goes beyond that, explains Maurice Ohayon, MD, PhD, coauthor of the study and director of the Sleep Epidemiology Research Center at Stanford University. Ohayon says people experiencing sleep drunkenness often don’t have any recollection of the things they say or do. While most episodes are short—typically less than 15 minutes—a small percentage of sleep drunkenness sufferers can become violent.  MORE: 20 Ways to Sleep Better Every Night  While that 15% figure includes people who experience sleep drunkenness very occasionally—like once or twice a year—Ohayon and his colleagues found about 8% of the roughly 19,000 people included in his study suffered from weekly bouts of sleep drunkenness. Taking psychotropic medications (such as antidepressants), feeling anxious or depressed, and sleeping too much, too little, or drinking alcohol are all factors that increase your risk for sleep drunkenness, he explains. Basically, any sleeping problems or mental health disorder raises your risk for episodes of the condition, his research shows. Should you worry? That depends. Experiencing sleep drunkenness could be a sign that you’re not sleeping enough or that you’re sleeping poorly, Ohayon says. You or someone you care about could also be at risk from your confused behavior, although in the vast majority of cases the disorder doesn’t lead to any scary or violent behavior, his research shows.  While it’s unclear what exactly causes the condition, Ohayon and his colleagues refer to sleep drunkenness as a kind of “severe sleep inertia”—as though a part of your brain decides to snooze while the rest of you gets moving. While you’re probably not in any danger from the disorder, Ohayon says it’s best to talk with your doctor about sleep drunkenness if you experience it frequently. “Getting more sleep, setting a more regular sleep-wake schedule, and avoiding alcohol in the evening might help to reduce the number of sleep drunkenness episodes you experience,” he says. MORE: 5 Signs You’re Sleep Deprived