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How do painters represent motion in garments? Graphic invariants across centuries.

Western visual art has radically changed throughout the centuries: different techniques, interest in the representation of reality, and use of graphic signs. Indeed, only a few pictorial cues have retained the same meaning and use. These kinds of graphic invariants may play a key role not only in a comparative study of art history, but also for discovering underlying common perceptual mechanisms. Here the aim is to show that western painters use the same graphic solutions to represent motion in garments, across countries and centuries. A pilot experiment, using 160 paintings representative of all main western European art movements from the thirteenth to the twentieth century, shows that different artists represented the motion of garments with the same orientation, curvature and convergence of lines. Experiment 1 demonstrates, with a smaller sample of paintings (16, i.e. two per century) that the relationship between orientation, curvature and convergence of lines is a good predictor of perceived motion. Experiment 2 shows how the same garments, isolated from the context of the paintings, still give different dynamic impressions according to the same rules. Finally, Experiment 3 confirmed the same results, whilst patterns previously used are simplified to their geometrical structure. These results call for an underlying perceptual mechanism that specifically recognizes orientation, curvature and parallelism levels as cues of motion in a static pattern.