A-02 · Attention & Perception
Two nearly identical scenes alternate in front of you. Something large keeps changing. Finding it is harder than you think.
Experimental design
Within-subjects; flicker paradigm with masked motion transients
Change blindness
Failure to notice a large visual change across successive views of a scene
Motion transient
Low-level signal produced when a region changes luminance or position between frames
Flicker paradigm
Rapid alternation of pre-change and post-change images separated by a blank mask
Transsaccadic integration
Combining information across eye movements; change detection often fails when transients are masked.
Mudsplash
High-contrast distractors that do not cover the change but still impair detection (O'Regan et al., 2000).
Change blindness blindness
Metacognitive overconfidence in one's ability to detect changes (Levin et al., 2000).
Difficulty
StandardEstimated time
10 minutes
Paradigm
Change blindness
First published
1997
Your visual system does not keep a photographic buffer of the world. Between glances, it stores only what was attended. Interrupt the motion signal that normally flags a change, and even large changes become invisible.
Ronald Rensink, Kevin O'Regan and James Clark formalized the 'flicker paradigm' in 1997: alternate an original and a modified photograph with a brief blank between them. The blank masks the motion transient that would normally capture attention, so observers must serially search the scene with focused attention to find the change. Search times stretch to tens of seconds even for changes in the center of interest, showing that scene representations are far sparser than subjective experience suggests.
Rensink, R. A., O'Regan, J. K., & Clark, J. J. (1997). To see or not to see: The need for attention to perceive changes in scenes. Psychological Science, 8(5), 368–373.