richard has pioneered the use functional magnetic resonance centre imang, has done a lot of very important work with it and that has been very important foallowing us to understand perception of faces. may i have the next image please. one ofhe really interesting agnosias and one we'll hear about from chuck close is blindness face. called prosagnosia. this is people can recognize all kinds of objects but they have difficulty recognizing a face. and this is discovered in around 1947 by johan-- who had several patients. one patient was a young guy who was shot in the head, almost died, survived, everything came back, all of his visual senses, his memory, everything was-- but he had difficult with one thing, conot recognize faces. you couldn't recognize his family, couldn't recognize friends. he couldn't recognize his own image when he looked in e mirror. he realized that there are different forms of agnosias, of they vary somewhat from each other. he saw two other patients with the same thing with. time after he came along one realized there are two forms. a congenital form and the quiet-- a