Explaining Eye Movements in the Visual Search of Varying Density Layouts

This research advances computational cognitive modeling of visual search, and the synergistic relationship between cognitive modeling and eye tracking. The paper presents cognitive models of the perceptual, cognitive, and motor processing involved in the visual search of words in structured layouts that vary in density. The layouts are allsparse, all-dense, or mixed. A principled approach is taken to account for eye movement data, specifically the mean number of fixations per trial and mean fixation durations. A random search strategy without replacement is used as a base model. The best-fitting model assumes that people examine two to three items per fixation regardless of the density. A new implementation of the EPIC cognitive architecture is used to build the models in this study. Modeling adjustments necessary to account for the data are discussed.