Optimal cue selection strategy

Vidhya Navalpakkam, Laurent Itti

Abstract: Survival in the natural world demands the selection of relevant visual cues to rapidly and reliably guide attention towards prey an d predators in cluttered environments. We investigate whether our visu al system selects cues that guide search in an optimal manner. We formall y obtain the optimal cue selection strategy by maximizing the signal to noise ratio (S N R) between a search target and surrounding distractors. This optimal strategy successfully accounts for several phenom ena in visual search behavior, including the effect of target-distracto r discriminability, uncertainty in target's features, distractor heterogenei ty, and linear separability. Furthermore, the theory generates a new predict ion, which we verify through psychophysical experiments with human subj ects. Our results provide direct experimental evidence that humans sel ect visual cues so as to maximize S N R between the targets and surrounding clutter.