Slow speech. Confused thinking. Inappropriate behavior. Blunt responses to questions or requests. Impaired motor skills. Nodding off. Not remembering what just happened.Sounds like any number of Saturday nights. But what is being described here is actually a sleep disorder that scientists now think may affect as many as 1 in 7 people.

Appropriately called “sleep drunkenness,” the disorder is characterized by extreme difficulty waking up, followed by confusion—for instance, “Even after a cold shower, a person with [the disorder] may resemble a drunken person.” answering the phone instead of turning off the alarm—and often falling right back asleep, with no memory of having gotten up in the first place. If a person does stay awake, the confusion can last for half an hour or more.

“Even after a cold shower,” writes Russel A. Dewey, Ph.D., in his intro psych textbook, “a person with [the disorder] may resemble a drunken person.”

The American Academy of Sleep Medicine (AASM) files sleep drunkenness under the category of confusion arousals, which it estimates affect about 3 to 4 percent of adults. New research from Stanford University School of Medicine studied the sleep habits of over 19,000 people and puts the estimate at more like 15 percent for sleep drunkenness alone. And, the study says, more than half of the people who reported getting sleep-hammered said it happened more than once a week. Sleep drunkenness occurs often in people who are sleep deprived and in people who get nine hours of sleep or more.

Sleep drunkenness can be occasionally dangerous, as some slumberers get violent when roused, and researchers have known about the disorder for decades, yet it’s stayed pretty much under the covers until, this week, when the Stanford researcher, Maurice M. Ohayon, M.D., Ph.D., published the new findings in the journal Neurology. “These episodes of waking up confused have received considerably less attention than sleepwalking even though the consequences can be just as serious,” Ohayon said in a statement.Sleep drunkenness occurs often in people who are sleep deprived and in people who get nine hours of sleep or more (aka hypersomnia, which is no good for your health anyway), and one study posits that it affects people with such high sleep requirements that they can never get enough.How do you know if you’re a sleep drunk? The AASM offers this quick test:

  1. Has someone told you that you act in a way that is strange or confused when they wake you?
  2. Has this behavior been described as being hostile or aggressive?
  3. Have these actions been inappropriate in any way?
  4. Is this a pattern of behavior that occurs on a regular basis?

“If your answer to each of these questions is yes,” it continues, “then you might have confusional arousals. Because you may have no memory of the events, it can be hard for you to know on your own.”And that’s why god gave us Sharpies and camera phones.

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