The FloatersДЄ good example of an optical illusion вЂ“ one that actually occurs inside the eye вЂ“ is floaters.ДЇloaters are small specks, spots or shadowy shapes that seemingly float in your field of vision. 'An illusion is a phenomenon in which our subjective perception doesn't match the physical reality of the world.'ДЄlthough people popularly call some brain teasers 'optical illusions,' this might not be the best term for them, as scientists make a distinction between optical illusions and what they call visual illusions.ДЄn optical illusion suggests that the illusion arises because of some properties of the eye, Bach pointed out.Д«ut since optical illusions are rare, a better and more accurate term is 'visual illusions,' because this helps to explain why these perceptions happen.

Susana Martinez-Conde, director of the laboratory of visual neuroscience at Barrow Neurological Institute in Phoenix, Ariz. Illusions, he said, may serve as a test bed to determine whether scientists understand vision correctly. In other words, your perception of an illusion has more to do with how your brain works - and less to do with the optics of your eye.ДЄn illusion is 'a mismatch between the immediate visual impression and the actual properties of the object,' said Michael Bach, a vision scientist and professor of neurobiophysics at the University of Freiburg Eye Hospital in Freiburg, Germany, who studies illusions and has a large collection of them on a Web site.Д®verything that enters the senses needs to be interpreted through the brain - and these interpretations occasionally go wrong, Bach told.

Visual illusions occur due to properties of the visual areas of the brain as they receive and process information.

Thebrain 9 virtual thoughts