On the timing of overt attention deployment: Eye-movement evidence for the Priority Accumulation Framework

The interpretation of many well-established findings rests upon the assumption that at any given moment attention is automatically allocated to the peak of a priority map, which is determined by physical salience, goals, and selection history. The Priority Accumulation Framework (PAF) challenges this assumption. It suggests that the priority weight at each location accumulates across successive events and that evidence for the presence of action-relevant information contributes to determine when attention is deployed to the location with the highest accumulated priority. Here, we tested these hypotheses for overt attention by recording eye saccades in a free-viewing spatial-cueing task. We manipulated search difficulty (Experiments 1 and 2) and cue salience (Experiment 2). Standard theories posit that when oculomotor capture by the cue occurs, it is initiated before the search display appears; therefore, these theories predict that the cue’s impact on the distribution of first saccades should be independent of search difficulty but influenced by the cue's saliency. By contrast, PAF posits that the cue can bias competition later, after processing of the search display has already started, and therefore, predicts that such late impact should increase with both search difficulty and cue salience. The results supported PAF’s predictions. Our findings call for a revision of visual search theories that have developed around the concept of a priority map without integrating the insights from research on temporal attention.