Daniel Segura PGS 101 10-22-99 Poggendorff Illusion This simulation I enjoyed partly because it was easy to do and clearly understandable. Perceptual illusions involve consistent errors in the perception of objective reality. It is believed that the study of illusions will help us to understand Fundamental operations of perceptual systems. Line- based illusions involve misperceptions regarding line length, angle or position, and there are a number of accounts as to why line-based illusions exist (Gilliam 210…showed first 75 words of 260 total…

…showed last 75 words of 260 total…the box became narrower. As the line adjusted from a thirty to forty-five then to a sixty degree angle my accuracy decreased. It is hypothesised that, over all illusions, the magnitude of errors will be reduced after pratice. So the more you practice the better you become at accurately placing the line in the correct position on the other side. Bibliography Referance: Gilliam, Barbara, 1971. "A depth processing theory of the Poggendorff illusion," Perception & Psychophysics, 10, 211-216.