Optical illusion, the term itself suggests that it is a deception or a visual deception. The images of an optical illusion are made or designed in such a way that they appear tricky when observed carefully. Our eyes process the visual information to the brain. The image or percept that it conveys does not fit in with physical dimensions of the stimulus source. This creates two entirely different images or percepts.
The physiological illusions occur naturally. Generally, our brain retains an image for one tenth of a second and our eyes or brain produces such effects of illusion due to alteration of perception. This happens as a reaction to over exposure of our eyes and brain to colour, brightness, tilt, movement et cetera. Cognitive illusions apply special visual tricks that shake assumptions about the world. For example: Penrose triangle and the staircase illusion.
The physiological illusions occur naturally. Generally, our brain retains an image for one tenth of a second and our eyes or brain produces such effects of illusion due to alteration of perception. This happens as a reaction to over exposure of our eyes and brain to colour, brightness, tilt, movement et cetera. Cognitive illusions apply special visual tricks that shake assumptions about the world. For example: Penrose triangle and the staircase illusion.