American scientist (1880 - 1955) who studied optics and the psychology of visual perception. He concluded that much of what a person sees depends on what he or she expects to see, based (consciously or unconsciously) on previous experience. He is best remembered for one of his creations that is named after him, the perceptual illusion of the Ames room. Ames rooms can be found in many places, most of them amusement parks. The sensation they provide is strange and bizarre, which demonstrates how our brains can be fooled by clever mechanisms.