Changing perspective: zooming in and out during visual search.
Laboratory studies of visual search are generally conducted in contexts with a static observer vantage point, constrained by a fixation cross or a headrest. In contrast, in many naturalistic search settings, observers freely adjust their vantage point by physically moving through space. In two experiments, we evaluate behavior during free vantage point (FVP) search, using observer-controlled zooming to simulate movement toward or away from search objects. We focus on scope fluctuations--repeated reversals in the direction of zooming during search. We found increased fluctuation when search items were sparse (Experiment 1) or of mixed size (Experiment 2). We propose that during FVP search, observers attempt to maximize the number of simultaneously discriminable items. Scope fluctuations emerge when maximizing does not enable simultaneous access to all search items, or when observers become disoriented in the search environment, necessitating repeated switches to a broad scope to reorient.
Department of Psychology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1. gsolman@uwaterloo.ca
Grayden J F
GJ
Solman
J Allan
JA
Cheyne
Daniel
D
Smilek
D001288:Attention; D004192:Discrimination, Psychological; D004215:Distance Perception; D005260:Female; D006801:Humans; D008297:Male; D009949:Orientation; D010364:Pattern Recognition, Visual; D011601:Psychophysics; D011930:Reaction Time; D012858:Size Perception; D013334:Students / Q000523:psychology