Capture of Attention by Visual Onsets

The appearance of a new object within a multiple item display has been shown to capture attention in a stimulus-driven manner. Capture may be either beneficial or detrimental to performance depending on whether the new object is a target or distractor. In the present study we show that the ability of new objects to capture attention is mediated by the number of objects that change or morph. This finding establishes a boundary condition of the phenomena of attentional capture and has implications for the design of complex displays.