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Jennifer S DiMase

Publications and source records attributed to Jennifer S DiMase.

2 recordsLinked to original sources

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.

Attention↗

Do intersections serve as basic features in visual search?

The status of 'intersection' as a basic feature in visual search tasks has been controversial. Under some circumstances, a target possessing this attribute (eg a plus) 'pops out' of a display of distractors that lack the attribute (eg Ls). However, those cases may be artifacts of other features such as relative size or number of line terminators. We report two sets of experiments with stimuli intended to control for these factors. Search for the presence or absence of intersections is very inefficient with these stimuli. The results suggest that intersection should not be included among the list of salient features that support efficient search through visual displays.

Adolescent↗