Perceptual Science Series
Delusions about illusions (talk recording available)
Dr. Brian Rogers
Wednesday, March 30, 2016, 12:00pm - 01:30pm
University of Oxford, Department of Experimental Psychology, Medical Sciences Division
The idea that our perceptions can be incorrect can be traced back to the ancient Greeks. In the 11th century, Al-Haytham drew a distinction between errors of sight (illusions) in “pure sensation”, in “recognition” and in “inference”. More recently, Gregory (1994) has made a similar distinction between three causes of illusions - “physical”, “physiological” and “cognitive”. Robinson (1972) attempted to group illusions according to the sensory dimension involved e.g. movement, depth, brightness and shape. What these different classifications have in common is that they all assume there is meaningful distinction between those aspects of perception we label as ‘illusory’ and those labelled ‘veridical’. However, this assumes there is an appropriate way to define the ‘physical reality’ used to assess the veridicality our perceptions. I would like to argue that there is no meaningful way of distinguishing between those perceptual effects we label as ‘illusory’ and those labelled as ‘veridical’ - all of our perceptions depend on the particular characteristics of the underlying mechanisms. As a consequence, I would like to propose a new way of classifying perceptual effects that is based on a set of characteristics common to all perceptual mechanisms.
Dr. Brian Rogers (ROOM CHANGE, RuCCS Room A139)