Coprolalia

Coprolalia is involuntary swearing or the involuntary utterance of obscene words or socially inappropriate and derogatory remarks. Coprolalia comes from the Greek κόπρος (kopros) meaning "feces" and λαλιά (lalia) from lalein, "to talk". The term is often used as a clinomorphism, with "compulsive profanity" inaccurately referred to as being Tourette syndrome.

Related terms are copropraxia, performing obscene or forbidden gestures, and coprographia, making obscene writings or drawings.

Coprolalia encompasses words and phrases that are culturally taboo or generally unsuitable for acceptable social use, when used out of context. The term is not used to describe contextual swearing. It is usually expressed out of social or emotional context, and may be spoken in a louder tone or different cadence or pitch than normal conversation. It can be a single word, or complex phrases. A person with coprolalia may repeat the word mentally rather than saying it out loud; these subvocalizations can be very distressing.

Coprolalia is an occasional characteristic of Tourette syndrome, although it is not required for a diagnosis of Tourette's. In Tourette syndrome, compulsive swearing can be uncontrollable and undesired by the person uttering the phrases. Involuntary outbursts, such as racial or ethnic slurs in the company of those most offended by such remarks, can be particularly embarrassing. The phrases uttered by a person with coprolalia do not necessarily reflect the thoughts or opinions of the person.

Cases of deaf Tourette patients swearing in sign language have been described, showing that coprolalia is not just a consequence of the short and sudden sound pattern of many swear words.

Coprolalia is not unique to tic disorders; it is also a rare symptom of other neurological disorders. It may occur after injuries to the brain such as stroke and encephalitis; in other neurological conditions such as choreoacanthocytosis, seizures, and Lesch–Nyhan syndrome; and rarely in persons with dementia or obsessive-compulsive disorder in the absence of tics.

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