Sleep-talking

In 1966, researchers worked to find links between heredity and sleep-talking. Their research suggests the following:

• Sleep-talking parents are more likely to have children who sleep-talk.
• Sleep-talking can still occur, though much less commonly, when neither parent has a history of sleep talking.
• A large portion of people begin to sleep-talk later in life without any prior history of sleep-talking during childhood or adolescence.

Sleep-talking by itself is typically harmless; however, it can wake others and cause them consternation—especially when misinterpreted as conscious speech by an observer. If the sleep-talking is dramatic, emotional, or profane it may be a sign of another sleep disorder. Sleep-talking can be monitored by a partner or by using an audio recording device; devices which remain idle until detecting a sound are ideal for this purpose.

Polysomnography (sleep recording) shows that episodes of sleep talking that can occur in any stage of sleep.[1]

Stress can also cause sleep talking.[2] In one study, about 30% of people who had PTSD (post-traumatic stress disorder) talk in their sleep.[3] A 1990 study showed that Vietnam War veterans having PTSD report talking more in their sleep than in people without PTSD.[4]

Sleep-talking can also be caused by depression, sleep deprivation, day-time drowsiness, alcohol, and fever. It often occurs in association with other sleep disorders such as confusional arousals, sleep apnea, and REM sleep behavior disorder. In rare cases, adult-onset sleep-talking is linked with a psychiatric disorder or nocturnal seizure.[5]

Sleep-talking is very common and is reported in 50% of young children at least once a year.[6] A large percentage of people progressively sleep-talk less often after the age of 25. A sizable proportion of people without any episode during their childhood begin to sleep-talk in adult life.[7] Sleep-talking may be hereditary.[8]

In a study reporting the prevalence of sleep-talking in childhood, the authors reported that the frequency of sleep-talking differs between children. About half of the children have sleep-talking episodes at least once a year, but less than 10% of children present sleep-talking every night, whereas 20% to 25% talk in their sleep at least once a week. In addition, they did not find any difference between gender or socioeconomic class.[6]

However, valid estimation of the prevalence of this phenomenon is difficult as the sleep-talker either does not remember or are not aware of their sleep-talking. The same uncertainty exists concerning the age of onset because early occurrences may have escaped notice. Thus, there are disparate results regarding its prevalence in the literature.[9]

Usually, treatment is not required for sleep-talking because it generally does not disturb sleep or cause other problems.[9][10]

One behavioral treatment has shown results in the past. Le Boeuf (1979) used an automated auditory signal to treat chronic sleep-talking in a person who had talked in his sleep for 6 years. An aversive sound was produced for 5 seconds when he started talking in his sleep. Sleep-talking was rapidly eliminated, and the person demonstrated no adverse effects of treatment.[11]

Sleep-talking appears in Shakespeare's Macbeth, the famous sleepwalking scene. Lady Macbeth, in a "slumbery agitation", is observed by a gentlewoman and doctor to walk in her sleep and wash her hands, and utter the famous line, "Out, damned spot! out, I say!" (Act 5, Scene 1).[12]

Sleep-talking also appears in The Childhood of King Erik Menved, a 19th-century historical romance by Danish author Bernhard Severin Ingemann.[13] In the story, a young girl named Aasé has the prophetic power of speaking the truth in her sleep. In an 1846 English translation, Aasé is described thus:

She is somewhat palefaced; and, however blithe and sprightly she may be, she is, nevertheless, now and then troubled with a kind of dreaming fit. But that will wear off as she gets older. Her mother was so troubled before her; and I believe it runs in the family as I am not entirely free from it myself. I do not give much heed to such dreaming now; but she has never yet said anything, while in this state, that has not proved in a manner true; though she can discern nothing, by night or day, more than others may do when they are in their senses.

Walt Whitman wrote a now-lost novel based on Ingemann's romance, which he titled The Sleeptalker.[14]

In Lewis Carroll's Alice's Adventure's in Wonderland, Chapter VII, The Dormouse talks in his sleep, or at least seems to, and even sings in his sleep:

'You might just as well say,' added the Dormouse, who seemed to be talking in his sleep, 'that "I breathe when I sleep" is the same thing as "I sleep when I breathe"!'

Here the Dormouse shook itself, and began singing in its sleep 'Twinkle, twinkle, twinkle, twinkle—' and went on so long that they had to pinch it to make it stop.

• Dion McGregor, noted 20th-century sleep-talker

• Emery, Carla (1998). "Secret, Don't Tell: The Encyclopedia of Hypnotism". Acorn Hill Publishing. ISBN 9780965993036

• OSF Healthcare
• The Sleep Well
• Somniloquies in the form of albums and books by Bryan Lewis Saunders
• Filmmaker Adam Rosenberg's four-minute film of himself sleep-talking