rotating snakes

Always worth checking out, Things Magazine, refers us to an absolute treasury of optical illusions (previously) from Professor Akiyoshi Kitaoka, 北岡 明佳 of the psychology department of the College of Letters, Ritsumeikan University, best known for his modern interpretations of Gestalt theory and peripheral drift observations and intervention. The pictured is an example of a colour swamp whose apparent inset seems to move upon scrolling. The anomalous motions can cause disorientation, especially when presented serially, and viewer discretion is advised.