Mannerism

n. mode of behavior, particular way of acting; affectation, pretention

Mannerism is a period  of European painting, sculpture, architecture and decorative arts lasting from the later years of the Italian High Renaissance around 1520 until the arrival of the Baroque around 1600. Stylistically, it identifies a variety of individual approaches influenced by, and reacting to, the harmonious ideals associated with Leonardo da Vinci, Raphael, and early Michelangelo. Mannerism is notable for its intellectual as well as its artificial (as opposed to naturalistic) qualities.
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Man·ner·ism n. A distinctive behavioral trait; an idiosyncrasy. [more]Mannerism - Community and Resources

Noun
1. a behavioral attribute that is distinctive and peculiar to an individual
(synonym) idiosyncrasy, foible
(hypernym) peculiarity, specialness, specialty, speciality, distinctiveness
2. a deliberate pretense or exaggerated display
(synonym) affectation, pose, affectedness
(hypernym) pretense, pretence, pretending, simulation, feigning
(hyponym) attitude

(n.)
Adherence to a peculiar style or manner; a characteristic mode of action, bearing, or treatment, carried to excess, especially in literature or art.