Abstract
In visual search, faster response times occur when the target repeats its location or color across trials (Maljkovic & Nakayama, 1996, Percept Psychophys). This "priming of pop-out" (PoP) phenomenon occurs spontaneously in the absence of eye movements, but does it persist across eye movements? With every saccade, the retinotopic (eye-centered) coordinates of objects change, and spatial representations must be updated to accommodate spatiotopic (world-centered) locations. However, this updating process takes time and may depend on the spatiotopic location being task-relevant (Golomb et al, 2008 J Neurosci). PoP reflects regularities in our environment and would be most useful in spatiotopic coordinates, but it is thought to be an implicit process. Does PoP spontaneously update to spatiotopic coordinates after an eye movement? Participants fixated on a cross while six colored diamonds appeared in the periphery. They then reported which side of the uniquely colored diamond (the target) was cut off. On half of the trials the fixation cross stayed in the same location as the previous trial; on the other half fixation moved to a new location. When fixation moved, trials were compared in which the target appeared in the same spatiotopic, same retinotopic, or completely different location as the previous trial. We also compared trials in which target and/or distractor colors switched or repeated. Results showed that PoP for both location and color still occurred across intervening eye movements: participants were significantly faster if the target appeared at the same spatiotopic location compared to when it appeared at a different location. Faster RTs also occurred when either the previous target or distractor color repeated, regardless of whether fixation changed. These results demonstrate that PoP for both color and location survives an eye movement, and further, the PoP phenomenon may result from a higher-order process that functions in non-retinotopic, behaviorally relevant coordinates.
Meeting abstract presented at VSS 2012