Abstract

V. Navalpakkam, L. Itti, Search goal tunes visual features optimally, Neuron, Vol. 53, No. 4, pp. 605-617, Feb 2007. [2005 impact factor: 14.304] (Cited by 424)

Abstract: How does a visual search goal modulate the activity of neurons encoding different visual features (e.g., color, direction of motion)? Previous research suggests that goal-driven attention enhances the gain of neurons representing the target's visual features. Here, we present mathematical and behavioral evidence that this strategy is suboptimal and that humans do not deploy it. We formally derive the optimal feature gain modulation theory, which combines information from both the target and distracting clutter to maximize the relative salience of the target. We qualitatively validate the theory against existing electrophysiological and psychophysical literature. A surprising prediction is that it is sometimes optimal to enhance nontarget features. We provide experimental evidence toward this through psychophysics experiments on human subjects, thus suggesting that humans deploy the optimal gain modulation strategy.

Note: Also see commentary / preview entitled ``Paying Attention to Neurons with Discriminating Taste'' by A. Pouget and D. Bavelier, Neuron 2007;53(4):473-475.

Themes: Model of Bottom-Up Saliency-Based Visual Attention, Model of Top-Down Attentional Modulation, Computational Modeling, Human Psychophysics