A repetitive movement that is difficult, if not impossible, to control. Tics can affect any group of muscles. The most common are facial tics, such as eye- blinking, nose-twitching, or grimacing. Tics that affect the muscles used to produce speech are known as vocal tics, and can range from grunts or whistles to the repetition of complete words or phrases. Complex motor tics involve multiple, sequenced movements, and can include behaviors such as twirling in place, tapping a certain number of times, or stooping to touch the ground. Tics are believed to arise in differences in or damage to the basal ganglia, a structure deep within the brain that controls automatic movements and that also affects impulsivity.
* * *
Habitual, repeated contraction of certain muscles, resulting in stereotyped individualized actions that can be voluntarily suppressed for only brief periods, e.g., clearing the throat, sniffing, pursing the lips, excessive blinking; especially prominent when the person is under stress; there is no known pathologic substrate. SEE ALSO: spasm. SYN: Brissaud disease, habit chorea, habit spasm. [Fr.]
- convulsive t. SYN: facial t..
- t. de pensée a rarely used term for the habit of involuntarily giving expression to any thought that comes to mind. [Fr. of thought]
- t. douloureux SYN: trigeminal neuralgia. [Fr. painful]
- facial t. involuntary twitching of the facial muscles, sometimes unilateral. SYN: Bell spasm, convulsive t., facial spasm, palmus (1).
- glossopharyngeal t. SYN: glossopharyngeal neuralgia.
- habit t. a habitual repetition of some grimace, shrug of the shoulder, twisting or jerking of the head, or the like.
- local t. a t. of very limited extent, as the winking of an eye or a twitch of a finger.
- psychic t. a gesture or exclamation made under the influence of an irresistible morbid impulse.
- rotatory t. SYN: spasmodic torticollis.
- spasmodic t. a disorder in which sudden spasmodic coordinated movements of certain muscles or groups of physiologically related muscles occur at irregular intervals. SYN: Henoch chorea.
* * *
total ion current; Toxicology Information Center; trypsin inhibitory capability; tubulointerstitial cell; tumor- inducing complex

* * *

tic 'tik n
1) local and habitual spasmodic motion of particular muscles esp. of the face: TWITCHING
2) a habitual usu. unconscious quirk of behavior or speech

* * *

a repeated and largely involuntary movement varying in complexity from the twitch of a muscle to elaborate well-coordinated actions. Simple tics occur in about a quarter of all children and usually disappear within a year. Tics most often become prominent when the individual is exposed to emotional stress. See also Gilles de la Tourette syndrome.

* * *

(tik) (Fr. tēk) [Fr.] an involuntary, compulsive, rapid, repetitive, stereotyped movement or vocalization, experienced as irresistible although it can be suppressed for some length of time; occurrence is exacerbated by stress and diminished during sleep or engrossing activities. Tics may be psychogenic or neurogenic in origin and are subclassified as either simple, such as eye blinking, shoulder shrugging, coughing, grunting, snorting, or barking, or complex, such as facial gestures, grooming motions, coprolalia, echolalia, or echokinesis.

Medical dictionary. 2011.


Look at other dictionaries:

  • tic — tic …   Dictionnaire des rimes

  • TIC — Contraction musculaire brusque, involontaire mais consciente, le tic affecte d’un mouvement rapide et répété un endroit précis du corps, peu susceptible de changement. Il se manifeste à l’état de veille et, le plus souvent, chez des individus… …   Encyclopédie Universelle

  • tic — [voce onomatopeica]. ■ interiez. [voce imitativa di un rumore non forte, ma rapido e secco] ▶◀ ticche, ticchete. ● Espressioni: tic tac [riproduce il rumore di colpi lievi e regolari] ▶◀ ticche tacche, ticchete tacchete; tic toc [riproduce il… …   Enciclopedia Italiana

  • Tic — Tic, n. [F.] (Med.) A local and habitual convulsive motion of certain muscles; especially, such a motion of some of the muscles of the face; twitching; velication; called also {spasmodic tic}. Dunglison. [1913 Webster] {Tic douloureux}. [F., fr.… …   The Collaborative International Dictionary of English

  • Tic@'t — is an e learning Catalan society based at the University of Alicante. The courses organized by tic@ t are taught using Moodle. tic@ t was created in 2003 and has been offering its courses since then in Spain and in South America. The subjects of… …   Wikipedia

  • tic — m. neurol. Movimiento involuntario, habitual y estereotipado que se produce principalmente en la cara. Se producen en ciertas personas que presentan algún disturbio emocional y lo manifiestan con mayor frecuencia en situaciones emocionalmente… …   Diccionario médico

  • TIC — [Abk. für engl. total inorganic carbon = gesamter anorg. Kohlenstoff]: in mg/L Wasser anzugebende Belastung eines Abwassers mit gelöstem oder ungelöstem anorg. gebundenem Kohlenstoff, vgl. TOC. * * * Tịc , der; s, s [frz. tic, wohl laut u.… …   Universal-Lexikon

  • tic — TIC. s. m. Sorte de maladie qui vient aux chevaux, & qui fait que de temps en temps ils ont une espece de mouvement de teste convulsif, & prennent la mangeoire avec les dents & la rongent. Un cheval qui a le tic. Tic, Se dit aussi d Une sorte de… …   Dictionnaire de l'Académie française

  • tic — (n.) twitching of a facial muscle, 1822, often a shortening of tic douloureux severe facial neuralgia, lit. painful twitch (1800), from Fr. tic a twitching disease of horses (early 17c.), of unknown origin. Klein suggests an imitative origin;… …   Etymology dictionary

  • tic — (plural tics) sustantivo masculino 1. Movimiento involuntario y repetido de una parte del cuerpo: un tic en los ojos. 2. Hábito o manía: No puede quitarse el tic de tocarse el pelo mientras habla. 3. Onomatopeya con que se imita un sonido seco y… …   Diccionario Salamanca de la Lengua Española

  • Tic — (fr. Tik), 1) das Krippenbeißen (s.d.) der Pferde; daher Tiquer, der Krippenbeißer; 2) das Gesichts od. Mienenzucken; Tic douloureux (spr. Tik duluröh), nervöser Gesichtsschmerz; 3) eine sonderbare, lächerliche Gewohnheit, Laune, Grille,… …   Pierer's Universal-Lexikon