CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during flicker (Rensink, O’Regan & Clark, 1997; 2000)

CB during Blinks (O’Regan, Deubel & Clark & Rensink, 2000)

CB during Blinks (O’Regan, Deubel & Clark & Rensink, 2000)

CB during Blinks (O’Regan, Deubel & Clark & Rensink, 2000)

• 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, real life– Levin & Simons, 1997

• “Mudsplashes”– O’Regan, Rensink & Clark (Nature, 1999)

Change Blindness

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

CB during Mudsplashes (O’Regan, Rensink & Clark, 1999)

detailed internalrepresentation

sparse ???

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”

• vividness through transients

Why we think we see everything

• Refrigerator light analogy (N. Thomas)– seeing is having access

Yarbus,1978

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”

• vividness through transients

de “voir”

l’illusion de

Visual solipsism

Visual solipsism

Simons & Chabris, 2000

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Haines, 1991. Ames Res. Center, NASA

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Central

Marginal

“Post-attentive vision”J. M. Wolfe, N. Klempen, and K. Dahlen (in press)

Repeated Search

80 ms 80 ms 80 ms

mask 30 ms mask

30 ms

Visual search has no memory

T. Horowitz & J.M. Wolfe (Nature, 1998)

“Inattentional Blindness” A. Mack & I. Rock (1998)

Normal trials

Critical trial

time

1.5 s 200 ms

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”

• vividness through transients

Visual Transients

• Attract attention to change location

• Impression of continuous presence

motion

orientation

color

xxxx

yyyy

MODULES

INFORMATION AVAILABLE:

Ron

Bag

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INFORMATION AVAILABLE:

INFORMATION ENCODED:

Ron

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x

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BAGCODED?

Bag

motion

orientation

color

xxxx

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TRANSIENTS IN MODULES....

INFORMATION AVAILABLE:

BAG DISAPPEARS!

RonHotel

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AFTERCHANGE

INFORMATION AVAILABLE:

(previously stored)

RonHotel

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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

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FLICKER

INFORMATION AVAILABLE:

(previously stored)

RonHotel

FootTable

x

y

z

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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

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D. Simons & D. Levin

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Using distracting local transients

• “Mudsplashes”– O’Regan, Rensink & Clark (Nature, 1999)

Ron

Pepsi

Footcompare

MUDSPLASH

INFORMATION AVAILABLE:

(previously stored)

RonHotel

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• 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

Chabrier & O’Regan, submitted

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Chabrier & O’Regan, submitted

Recent sources on CB

• Vis Cog 2000, 1/2/3 (Ed. Dan Simons)

• Fleeting Memories (Ed. V. Colthert) MIT Press, 1999

• http://www.wjh.harvard.edu/~viscog/change/

Recent issues on CB

• implicit memory, unconscious recall• layout

• cognitive description

• CB in dynamic scenes

• iconic memory, masking

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cette image.