VISUAL MARKING OF OLD OBJECTS

Watson and Humphreys (1997) presented evidence that selection of new e lements can be prioritized by on-line top-down attentional inhibition of old stimuli already in the visual field (visual marking). The exper iments on which this evidence was based always presented old elements in green and new elements in blue. Because of this, instead of priorit izing new objects by inhibiting old objects, selection could have been based on color. The present experiment, which does not contain this c onfound, showed that visual marking is a strong and robust process tha t enables subjects to visually mark at least 15 old elements even when these elements have the same color as the new elements. The results i ndicate that preview of the elements is critical-not the fact that tho se elements contained a common feature.