The most common word during sleep is "No," 10pct of speech are profanities and 26pct are interrogations

What does the sleeping brain say? Syntax and semantics of sleep talking in healthy subjects and in parasomnia patients. Isabelle Arnulf et al. Sleep, zsx159, https://doi.org/10.1093/sleep/zsx159

Abstract

Objectives: Speech is a complex function in humans, but the linguistic characteristics of sleep talking are unknown. We analyzed sleep-associated speech in adults, mostly (92%) during parasomnias.

Methods: The utterances recorded during night-time video-polysomnography were analyzed for number of words, propositions and speech episodes, frequency, gaps and pauses (denoting turn-taking in the conversation), lemmatization, verbosity, negative/imperative/interrogative tone, first/second person, politeness and abuse.

Results: The 232 subjects (aged 49.5 ± 20 y old; 41% women; 129 with rapid eye movement [REM] sleep behavior disorder and 87 with sleepwalking/sleep terrors, 15 healthy subjects and 1 patient with sleep apnea speaking in non-REM sleep) uttered 882 speech episodes, containing 59% non-verbal utterance (mumbles, shouts, whispers, laughs) and 3349 understandable words. The most frequent word was “No”: negations represented 21.4% of clauses (more in non-REM sleep). Interrogations were found in 26% of speech episodes (more in non-REM sleep), and subordinate clauses were found in 12.9% of speech episode. As many as 9.7% of clauses contained profanities (more in non-REM sleep). Verbal abuse lasted longer in REM sleep and was mostly directed towards insulting or condemning someone, whereas swearing predominated in non-REM sleep. Men sleep-talked more than women and used a higher proportion of profanities. Apparent turn-taking in the conversation respected the usual language gaps.

Conclusions: Sleep talking parallels awake talking for syntax, semantics and turn- taking in conversation, suggesting that the sleeping brain can function at a high level. Language during sleep is mostly a familiar, tensed conversation with inaudible others, suggestive of conflicts.

Keywords: sleep talking, language, syntax, linguistics, semantics, verbal abuse, REM sleep behavior disorder, sleepwalking


My comment: The most common word during sleep is "No," and 10pct of speech are profanities and 26pct are interrogations.