Why do some people sleep talk?

Research suggests that around 2 in 3 have talked in their sleep at least once in their lives. Although sleep talking is usually harmless, it can be embarrassing or relate to a sleep disorder. It can also pose difficulties for those sharing a bed or bedroom with a sleep talker.

This article will explore what constitutes sleep talking, what causes it, when you should seek medical advice and how you might manage the condition.

What is sleep talking?

Sleep talking is when a person talks during their sleep without being aware of it at the time and when they wake up. The content of the speech could range from complex conversations or monologues, to total gibberish or mumbling. However, sleep talking does not include other non-speech vocalisations that can occur during sleep, such as groaning or physically acting out dreams.

Sleep talking is closely associated with non-rapid eye movement (NREM) parasomnias (abnormal behaviours during sleep), such as sleeping walking and sleep terrors, and rapid eye movement (REM) parasomnias, such as nightmares. However, sleep talking can also occur in the context of sleep disorders like periodic limb movement disorder and obstructive sleep apnea.

It is difficult for researchers to fully understand the prevalence of sleep talking because individuals rarely remember an episode. However, sleep talking appears to be one of the most common parasomnia symptoms.

Episodes of sleep talking are usually infrequent and it can even take 4 nights for regular sleep talkers to experience an episode. Sleep talking is much more common in children and affects men and women just as frequently. In a study of 2,022 schoolchildren aged 3–10, half talked in their sleep at least once a year and there was no correlation between the frequency of sleep talking and age, sex or socioeconomic status.

What causes sleep talking?

It is unclear why people talk in their sleep. Some research indicates a genetic component as sleep talking can run in the family. Further, it is more common for sleep talking to occur alongside sleepwalking, teeth grinding and nightmares amongst twins than in the general population. Sleep talking is also more common in those with mental health conditions, particularly those with post-traumatic stress disorder.

It is true that sleep talking can sometimes be associated with dreams. There is some evidence that sleep talking is more comprehensible when it occurs during REM sleep, the stage of sleep associated with dreams. However, sleep talking can happen during NREM sleep, a stage of sleep that is less associated with dreaming.

Comprehensible sleep talking can be negative, exclamatory or profane, reflecting a conflict-driven dialogue taking place in the brain. However, half of recorded sleep talking was categorised as incomprehensible in a study and oftentimes the speech does not relate to the sleep talker’s life, recent events or prior conversations.

Should sleep talking be a cause for concern?

Sleep talking is generally not considered dangerous and does not indicate poor sleep quality. If only for the fact that sleep talking tends to occur so infrequently, it is not deemed to be the cause of serious problems.

There are some situations in which sleep talking could be an issue:

• It may disrupt the sleep of a person sharing a bed or bedroom with a sleep talker;
• The content of the speech may be embarrassing for the sleep talker;
• Sleep talking may be a component of other parasomnias, such as nightmare disorder or sleepwalking, which can be dangerous.

If you’re bothered by ongoing sleep talking, you suffer from other sleep problems or you experience excessive sleepiness during the day, then you should consult your doctor. Further, if your sleep talking occurs suddenly as an adult or if it involves intense fear, screaming or violent actions, then you should consider seeing a sleep specialist.

How can you stop sleep talking?

Normally, treatment is unnecessary due to the limited frequency of episodes and the minimal adverse consequences. However, if there is an underlying cause of the sleep talking such as OSA, then treating that underlying condition should resolve the sleep talking.

In the meantime, improving sleep hygiene may help those seeking treatment. Most parasomnias are thought to be an abnormal state that blends wakefulness and sleep. This state may be more likely to arise when normal sleep patterns are disturbed. Implementing healthy habits that promote adequate amounts of good quality sleep, including the optimisation of the sleep environment, will help to combat sleep disturbances.

How can those sleeping near sleep talkers get better sleep?

Those sharing a bed or bedroom with sleep talkers usually bear the brunt of the negative consequences of sleep talking. The noise created by sleep talkers may disrupt their sleep or they may be alarmed by the content of the sleep talker’s speech.

Wearing earplugs or headphones can help to block out the noise. A white noise machine or fan can create a soothing and stable background noise that drowns out most of the noise generated by the sleep talker. In some cases, it may be necessary for bed partners or roommates to sleep in separate rooms to preserve their sleep quality.