change blindness
a failure to notice changes in the visual array appearing in two successive scenes. This is surprisingly common whenever the brief movement (the transient) that usually accompanies a change is somehow masked or interrupted. In experimental investigations, the transient is often blocked by inserting a blank screen between the original image (e.g., a picture of an airplane) and the changed image (e.g., a second picture of the same airplane with an engine missing), or by scattering a few small, high-contrast shapes across the picture simultaneously with the change. Detection failures also occur when changes are made during blinks, saccades, and other natural occlusions, or when changes happen gradually and thus have no transients. Such failures have also been documented in such real-world situations as automobile accidents, eyewitness identifications, military operations, and everyday interpersonal interactions. Attention-based explanations for the phenomenon
attribute it to diversion of an individual’s focus from the changing object. Other theories postulate that failure to notice changes represents a failure to encode the visual information in working memory, generally because it was not relevant to task demands. Still other theories emphasize a failure to compare prechange and postchange mental representations of the visual environment. See also attentional blindness; inattentional blindness; mindsight; repetition blindness. [term coined in 1997 by Canadian psychologist and computer scientist Ronald A. Rensink and colleagues]