Visual illusions reveal wide range of cross-cultural differences in visual perception

Vision science largely ignores the fact that rural visual environments typical of our species’ history differ radically from urban zones from which almost all samples are drawn: Only a handful of paradigms have been used to investigate rural-urban differences in visual perception, and some show limited effects or suffer from limited methodologies. Here we more than double the total number of paradigms in this literature, including visual illusions assumed to rely on universal mechanisms (e.g. Gestalt shapes, Cafe wall, curvature blindness). Results reveal profound differences in visual phenomenology, with rural Namibian participants often failing to see percepts obvious to UK/US participants and vice versa. In sum, what is universal and what is culturally-constructed in human visual perception remains a wide-open area of research.