Overt attentional prioritization of new objects and feature changes during real-world scene viewing

The authors investigated the extent to which a change to an object's colour is overtly prioritized for fixation relative to the appearance of a new object during real-world scene viewing. Both types of scene change captured gaze (and attention) when introduced during a fixation, although colour changes captured attention less often than new objects. Neither of these scene changes captured attention when they occurred during a saccade, but slower and less reliable memory-based mechanisms were nevertheless able to prioritize new objects and colour changes relative to the other stable objects in the scene. These results indicate that online memory for object identity and at least some object features are functional in detecting changes to real-world scenes. Additionally, visual factors such as the salience of onsets and colour changes did not affect prioritization of these events. We discuss these results in terms of current theories of attention allocation within, and online memory representations of, real-world scenes.