Abstract
When visual objects are imbued with reward—usually in the form of monetary benefits—they become salient. As a result, they draw attention in a way not accounted for by traditional notions of top-down strategic goals and bottom-up physical salience. This ‘incentive salience’ has largely been investigated in experiments employing synthetic stimuli like geometric shapes characterized by saturated color. Much less is known about how incentive salience impacts processing of complex real-world stimuli. Here, we investigate the impact of financial reward on selective processing of natural categories of visual stimuli (cars, trees, people) presented in images of real-world scenes. We employed an experimental design in which one category of visual object was consistently rewarded when it was the target of search but could appear as an irrelevant distractor when search was for a different object category. Our hypothesis was that rewarded targets would acquire salience, and thus need to be visually suppressed when they acted as distractors. To test this, we used the N2pc and Pd ERP components – which track visual selection and suppression, respectively – to index processing of targets and distractors in our scene stimuli. Results show that suppression of reward-associated real-world distractors emerges rapidly. Reward thus appears to bind to categories of visually heterogenous naturalistic stimuli categories, creating the need for strong suppression when examples of reward-associated categories must be ignored.