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Tourette’s disorder

a tic disorder characterized by many motor tics and one or more vocal tics, such as grunts, yelps, barks, sniffs, or (rarely) coprolalia. The tics occur many times a day for more than a year, during which time any period free of tics is never longer than 3 months. The age of onset for the disorder is before 18 years; in most cases, it starts during childhood or early adolescence. Also called Gilles de la Tourette’s syndrome. [first described in 1885 by Georges Gilles de la Tourette (1857–1904), French physician]

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Psychology term of the day

March 12th 2025

classification rule

classification rule

a mathematical formula for placing units into groups (e.g., within discriminant analysis) so as to maximize the similarities among group members with regard to a set of characteristics. Also called allocation rule.