Change blindness

examples are from:

http://viscog.beckman.uiuc.edu/djs_lab/demos.html

Spot the change in the following images

Change blindness

• While a door is carried between an observer and one person, that person is replaced by a 2nd person. 50% of observers do not notice changes in identity

(Simons & Levin, 1998)

• Observers must attend to features to notice change

• Attention does not ensure memory of all features

Change blindness

• Subjects miss large changes during saccades (e.g. exchange of heads, Grimes 1996)

• Change is noticed by the motion between the original and new form of an item

• We miss change if it happens slowly or if an irrelevant transient (e.g. flash, occlusion, saccade) occurs between the original & new forms

Seeing Depends on Attention

• Inattention blindness events not seen

• Attention control problems (neglect) can mean that part of the world is selectively ignored

• Note hemi-spatial neglect from previous lecture (6)