Purchase this article with an account.
Brandon M. Liverence, Brian Scholl; Attentional selection increases the refresh rate of perception: Evidence from multiple-object tracking. Journal of Vision 2012;12(9):454. doi: 10.1167/12.9.454.
Download citation file:
© 2015 Association for Research in Vision and Ophthalmology.
Selective attention enhances accuracy and speeds responses in many perceptual tasks. In some cases, these enhancements may be probabilistic, e.g. reflecting an increased likelihood that an attentional spotlight will sample from selected (rather than background) objects at any given moment. Might attentional selection also lead to qualitatively different sampling? Here we explore the possibility that selection can alter the functional 'refresh rate' of perception. While fixating, observers tracked 2 out of 5 objects in a simplified multiple object tracking task. As they moved, the objects also rapidly changed colors (4-12 times per second, varied from trial to trial), and participants simultaneously monitored for probe events in which any 2 objects' changing colors momentarily became synchronized. Target-target probe detection was dramatically enhanced relative to target-distractor or distractor-distractor probe detection at every rate tested, with target-target detection on 12 Hz trials roughly equivalent to target-distractor (or distractor-distractor) detection on 4 Hz trials. (And this effect replicated for multiple visual features, including rapid shape changes.) Critically, baseline performance (as revealed by a control experiment with probe detection but no tracking) was also just as low as the target-distractor and distractor-distractor conditions, indicating that the selection effect reflects target enhancement rather than distractor impairment. Nontemporal accounts were unable to predict these data. For example, a deflationary interpretation wherein task demands simply kept observers from processing distractors would predict worse performance for distractor-distractor (and target-distractor) probes relative to baseline probes — but this was not observed. Data from additional control experiments also ruled out interpretations based on sampling of selected objects that was no more frequent, but instead was more synchronous, or involved higher-resolution samples. These data collectively suggest that attentional selection leads to more frequent sampling of selected objects — an increase in the functional refresh rate of perception.
Meeting abstract presented at VSS 2012
This PDF is available to Subscribers Only