Data Sets for Alerting Effects Occur in Simple - but not Compound - Visual Search Tasks

In simple visual search, a target (e.g., a square shape) must be singled out as a unique item from distractors (e.g., ring shapes). Generally, two effects are known to facilitate search performance: "alerting" (e.g., briefly brightening the screen before display onset) and "priming" (e.g., repeating the unique item on successive trials). Unlike simple search, compound search has two steps. For example: (a) locate the unique object in the display and (b) identify the tilt of a line inside that object. In the present work we examined the joint effects of alerting and priming in compound search. We found that alerting does occur in simple search but not in compound search, unless conditions allow the compound search to be performed as a simple search.