Author: Nuno Alexandre De Sá Teixeira

Country: Portugal

Description: In the Bending Strings Illusion, perfectly straight lines – here embedded in a guitar drawing to resemble its strings – appear squiggly or wavy when placed between straight dotted lines. The illusory squiggles appear stronger in peripheral vision. Several variations are presented, each affecting the illusion to different degrees. The behaviour of the illusion hints at the likely involvement of early visual mechanisms. I found this illusion while preparing a diagram for a class, with alternating straight and dotted lines – what at first seemed to be yet another software glitch turned out, after careful inspection, to be just an optical effect.