Speaking in sleep can be very embarrassing as the complete level of unconsciousness gives no possibility of control over what is said. But from a new study, the risk of being a sleep speaker is greater because the higher the chances are of saying offensive and dirty words during sleep.

The study led by Dr. Isabelle Arnulf found that the words spoken during sleep are often negative and belong to a vulgar vocabulary, which is addressed to another person.

The research team analyzed 232 adults, of whom 129 had sleep-disordered speech, 87 had experienced sleepwalking, and 15 others had no sleep disorders.

During the two nights of sleep, the researchers recorded what behavior participants would have during sleep. In conclusion 883 sleep-speaking incidents were recorded, which contained 3,349 intelligible words. The study found that the most commonly used word for slurred speech was "No." 24% of slurred speech contained negative vocabulary, while 22% of it contained dirty words. About 10% of slurred speech also contained oaths.

Why so many negative words?

Researchers believe that sleep speech occurs while we are in the REM period of sleep. This period is what contains intense and emotional dreams. These dreams can contain threatening situations, which explains the use of negative language.

The strange thing is that the use of grammar remains normal even in these situations.

"What we do know so far is that sleep speech is very similar to normal speech, in terms of a correct grammar, with well-constructed sentences, as well as breaks between which, apparently, is the time to return the answer of the other person in the dream ", - said Dr. Arnulf.

"The difference lies in the quality of the language used, which is a negative, rude and vulgar language that is addressed to someone else, not to themselves. "This suggests that the brain uses the same information network as it does when we are awake."

So if you are a night owl, you should probably apologize in advance to your sleeping partner, just to be okay.