Why do we think we see “everything”? Immediate availability at flick of eye/attention The “world as an outside memory”(O’Regan, 1992) refrigerator light analogy (N. Thomas) visual “solipsism”

Vision-inverting mirror Erismann (1947) Kohler (1951)

Kohler, 1951

Another of the training procedures he adopted was to walk round and round a chair or table, constantly touching it with his body, and frequently changing direction so as to bring both sides into action. It was during an exercise of this kind, on the eighth day of the experiment, that he had his first experience of perceiving an object in its true position. But it was a very strange experience, in that he perceived the chair as being both on the side where it was in contact with his body and on the opposite side. And by this he meant not just that he knew that the chair he saw on his left was actually on his right. He had that knowledge from the beginning of the experiment. The experience was more like the simultaneous perception of an object and its mirror image, although in this case the chair on the right was rather ghost-like. J.G. Taylor, 1962, p (the subject here was Seymour Papert, wearing left-right inverting spectacles, during an experiment he subjected himself to while visiting Taylor in Cape Town in 1953)

Why do we think we see “everything”? Immediate availability at flick of eye/attention The “world as an outside memory”(O’Regan, 1992) refrigerator light analogy (N. Thomas) visual “solipsism”

Why is seeing different from other mental phenomena? Corporality –tight link to body motions Alerting capacity –transients incontrovertibly grab attention

Corporality voluntary motions systematically affect input Don’t see objects but what you can do with them Children’s drawings Boundary completion (H. Intraub)

H. Intraub, et al.,

Alerting Capacity capacity to peremptorily interfere with cognitive processing visual transients

motion orientation color xxxx yyyy MODULES INFORMATION AVAILABLE: Ron Bag Hotel Foot Table x y z w r Soda iconic memory

select Ron Soda Foot INFORMATION AVAILABLE: INFORMATION ENCODED: Ron Bag Hotel Foot Table x y z w r Soda BAG CODED? Bag cf. Bundesen, 1990; Gegenfurtner & Sperling, 1993 Luck & Vogel, 1997 iconic memory short term visual memory

motion orientation color xxxx yyyy TRANSIENTS IN MODULES.... INFORMATION AVAILABLE: BAG DISAPPEARS! Ron Hotel Foot Table x y z w r Soda

Ron Soda Foot compare AFTER CHANGE INFORMATION AVAILABLE: (previously stored) Ron Hotel Foot Table x y z w r Soda Bag

Detecting changes normally transient indicates location and ‘flavour’ of change. if object previously coded: transient indicates change location comparison can be made if object not coded ‘flavor’ can be used to guess at change

Ron Soda Foot compare FLICKER INFORMATION AVAILABLE: (previously stored) Ron Hotel Foot Table x y z w r Soda Bag

Detecting changes when there are global transients if object coded: slow search for change location if object not coded: no hope.

Using a global transient Flicker –Rensink, O’Regan & Clark,1997; 1999 Eye saccades –Currie, McConkie, Carlson-Radvansky & Irwin, 1995; McConkie & Currie, 1996 Blinks –O’Regan, Deubel, Clark, Rensink, 1999 Film cuts –Levin & Simons, 1997

D. Simons & D. Levin

Using distracting local transients “Mudsplashes” –O’Regan, Rensink & Clark (Nature, 1999)

Ron Pepsi Foot compare MUDSPLASH INFORMATION AVAILABLE: (previously stored) Ron Hotel Foot Table x y z w r Soda Bag

Principle: render transients inoperative –Drowned by global transient: flicker, saccade, blink, film cut –Diversion by local transient (mudsplash) –No transient: slow change (R. Chabrier) Change blindness experiments

Auvray & O’Regan, 2003; Chabrier & O’Regan, unpublished

Recent sources on CB Visual Cognition 2000, 1/2/3 (Ed. Dan Simons) Fleeting Memories (Ed. V. Coltheart) MIT Press,

Recent issues on CB implicit memory, unconscious recall layout cognitive description CB in dynamic scenes iconic memory, masking

Why do we think we see “everything”? Immediate availability at flick of eye/attention The “world as an outside memory”(O’Regan, 1992) refrigerator light analogy (N. Thomas) visual “solipsism”

Why is seeing different from other mental phenomena? Corporality –tight link to body motions Alerting capacity –transients incontrovertibly grab attention

Remembering

Seeing

"raw feel"

Seeing is a SKILL Exercising the sensorimotor contingencies

Seeing is making an internal representation Seeing is knowing about things to do standard viewnew view

Brain creates experience standard view

Brain creates actions and has knowledge standard viewnew view Brain creates experience