Abstract
Abstract When a change occurs during steady viewing it produces a transient that attracts attention, thereby allowing an observer to notice the change. If, however, a change occurs simultaneously with the onset of a set of distractors, the distractors also produce transients that compete for attention, the change becomes difficult to detect resulting in “change blindness” (Rensink, O’Regan, & Clark, 1999). Becker and Vera (2007) found that change blindness is dramatically reduced if the distractors flash many times before appearing with the change. In their experiments the distractors always flashed 14 times before appearing with the change. Here we present a paradigm similar to Becker and Vera’s but vary the number of flashes that precede the change. It is possible that multiple flashes are required to create and/or strengthen an attentional filter to improve change detection. However, it is also possible that a single preview of distractors visually mark the distractors resulting in improved change detection (Watson and Humphreys, 1997). Participants detected a single letter change among a circle of letters. In control trials there were no distractors, in experimental trials the letter changed with a simultaneous flash of distractors. Experimental trials also varied in the number of preceding flashes: zero (classic change blindness situation), one, two, four, or eight. Consistent with previous work, having a simultaneous flash of distractors disrupted change detection and preceding flashes improved change detection compared to no previous flashes. Importantly, only a single preceding flash was required to see the dramatic improvement in change detection rates, and a single preceding flash was roughly as effective as eight preceding flashes. That is, the effect did not build up over multiple flashes. This pattern of results suggests that participants visually mark the distractors after a single previous presentation and are then able to ignore the subsequent distractor onsets.
Meeting abstract presented at VSS 2015