Attentional pursuit is faster than attentional saccade.
How quickly can we shift the focus of visual attention? We compared the rates of two types of attentional shifts: attentional saccades (shifts between objects) and attentional pursuit (shifts along with a moving object). Instead of measuring the time required for a single shift, which confounds shift time with cue interpretation time, we measured the pace at which observers could make multiple successive shifts in a predictable order. We find that successive attentional saccades between objects are quite slow (300-500 ms). The object-based theory of attention predicts that attention should shift between locations more quickly when in pursuit of a moving object. Our results support this theory. Attentional pursuit is substantially faster--taking only 200-250 ms to cover the same distance. "Indexing" a moving object (keeping track of one object) can be done at even faster rates, supporting a distinction between attending to and indexing objects.
Visual Attention Laboratory, Brigham & Women's Hospital, and Department of Ophthalmology, Harvard Medical School, Boston, MA, USA. toddh@search.bwh.harvard.edu
Todd S
TS
Horowitz
Alex O
AO
Holcombe
Jeremy M
JM
Wolfe
Helga C
HC
Arsenio
Jennifer S
JS
DiMase
D001288:Attention / Q000502:physiology*; D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D011698:Pursuit, Smooth / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D013997:Time Factors