In action-control research, typically, stimulus sparse displays are used. This might be one reason why previous theorizing focuses on the (top-down) demands of response selection (e.g., what key to press), while often ignoring (bottom-up) demands of stimulus selection (e.g., what stimulus to attend). However, complex perceptual situations may pose selection demands that make additional, response-unrelated feature dimensions relevant for response selection. The major stimulus characteristic affecting perceptual selection is salience. In research on visual attention, there is a debate about the conditions under which salience becomes effective. We related both debates in two experiments, in which we modulated display set size as well as salience in a stimulus-response binding task. In sum, the data of these experiments (pooled N = 138) demonstrated that salience furthered the integration of stimulus features in displays with many stimuli more than in sparse displays. Our results demonstrate the neglected impact of salience on action-control when going beyond the very simplistic displays common in action-control research.
Public Significance StatementIn research on the question of how humans act, experimental displays comprise usually only very few stimuli. We argue that this has led to an underestimation of an important variable that influences the selection of sensory information, namely salience. In complex selection situations, that is, most everyday situations outside the laboratory, salience guides human attention toward potentially relevant objects or areas. We show that this holds true for action research if action experiments require more than the typical, artificially low selection demands.