Abstract
When searching through a scene, saccades tend to be slower to return to recently fixated locations (saccadic inhibition), whereas during scene memorization saccades tend to be faster to such locations (Dodd et al., 2009). Is the lack of evidence for inhibited saccades in tasks emphasizing scene memory a consequence of a goal-dependent mechanism or is the inhibition simply masked by other processes involved in scene memorization but not search? We provide evidence for the latter. Using an interrupted scene search task (Experiment 1) in which scenes abruptly expanded in size—which is considered to invoke memorial processes (cf. Thomas & Lleras, 2009)—we were able to eliminate saccadic inhibition. Moreover, applying a spatial working memory load prior to search further reduced search efficiency such that saccades were now faster to return to recently fixated locations. To test whether an additional memory process—brought online by scene interruption—obscured saccadic inhibition, Experiment 2 employed a continuous scene search task in which scenes remained continuously present throughout search. In this case, saccadic inhibition was observed, regardless of whether a spatial working memory load was applied or not. Thus, spatial working memory influenced interrupted but not continuous scene search. These data suggest that when confronting visual instability, processes related to working memory are brought online, obscuring saccadic inhibition and thus rendering search less efficient in the sense that rather than the eyes being propelled through the scene, the eyes are instead biased to return to an already fixated location.
Meeting abstract presented at VSS 2018