Why Do I Talk In My Sleep?

Watching someone talk in their sleep can be funny and sometimes even scary, but what's happening in the brain when this takes place?

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Somniloquy is the technical term for talking in your sleep. For some unknown reason, some of us sleep comfortably and quietly, whereas others will blurt out words, sentences--even entire speeches--while they're fast asleep. As your body falls asleep, your brain's reticular activating system (RAS) hands control over to the ventrolateral preoptic nucleus (VLPO). Once you're asleep, your brain releases two compounds: glycine and GABA. These chemicals essentially paralyze your body: they keep your vocal chords, mouth, and body muscles from moving while you're asleep. This is why you don't "act out" what's happening in your dreams.

Scientists have no idea why some people are able to talk in their sleep. Sleep talking can occur at any time during the sleep cycle: people can sleep talk whether or not they're dreaming. Researchers believe that some people might slip through the paralyzing net of glycine and GABA and end up voicing what's happening inside their head. Sleep talking is related to sleepwalking and night terrors: about half of all children and five percent of adults will talk in their sleep. It's more common among men than women, another fact that sleep researchers don't understand.

A study of over 2,000 schoolchildren published in the journal Brain and Development found that while about 10 percent of children will sleep talk every night, 50 percent will do so once a year. Another study in Pediatrics found that most childhood sleep abnormalities declined by age 13...but not sleep talking. Other than the chance of waking up your partner, sleep talking is not harmful. However, if people continue to experience it after age 25, the National Sleep Foundation recommends seeking professional help. They say that adult somniloquy can be brought on by stress, fever, sleep deprivation, alcohol or drugs, or something more serious, like depression. Limiting caffeine at night, avoiding screens, and keeping a regular sleeping hours all decrease instances of sleep talking in adults.

Have you or someone you've slept with ever experienced somniloquy? Let us know your experiences by leaving a comment down below. As always, we love to hear from you, regardless if you're awake or asleep.

Learn More:

Why Do People Talk In Their Sleep? (Live Science)
"Almost all of us have at some point been told that we were talking in our sleep the night before. It can be a disturbing thing to hear."

Sleep Talking - Causes (National Sleep Foundation)
"Sleep talking may be brought on by stress, depression, fever, sleep deprivation, day-time drowsiness, alcohol, and fever. In many instances sleep talking runs in families, although external factors seem to stimulate the behavior."

Prevalence of sleep-talking in childhood (Brain & Development)
"This report is on the prevalence of somniloquy, as revealed by a populational survey of 2,022 schoolchildren aged from 3 to 10 years."