Visual illusions: brain and consciousness

Visual illusions are not just entertaining, but represent ideal means for testing empirical questions on the neurobiology of vision and underlying cognitive processes. A variety of visual illusions will be introduced and possible underlying mechanisms will be discussed, including retinal and cortical approaches and how such illusory phenomena can be created in order to test specific research questions. Typically, someone discovers a new visual illusion and scientists then try to explain why and how it occurs. However, the other way around may be of interest as well: creating certain illusions on the basis of our knowledge about the visual system. Furthermore, we are sometimes aware of being tricked by these patterns but cannot overcome the illusory effects. Therefore, another important question is: what is the role of consciousness in the perception of visual illusions?