Differences in multiple-target visual search performance between non-professional and professional searchers due to decision-making criteria.

Professional visual searches, such as those conducted by airport security personnel, often demand highly accurate performance. As many factors can hinder accuracy, it is critical to understand the potential influences. Here, we examined how explicit decision-making criteria might affect multiple-target search performance. Non-professional searchers (college undergraduates) and professional searchers (airport security officers) classified trials as 'safe' or 'dangerous', in one of two conditions. Those in the 'one = dangerous' condition classified trials as dangerous if they found one or two targets, and those in the 'one = safe' condition only classified trials as dangerous if they found two targets. The data suggest an important role of context that may be mediated by experience; non-professional searchers were more likely to miss a second target in the one = dangerous condition (i.e., when finding a second found target did not change the classification), whereas professional searchers were more likely to miss a second in the one = safe condition.