Attentional blink and attentional capture: endogenous versus exogenous control over paying attention to two important events in close succession.

Identification of the second of two targets is impaired if it is presented less than about 500 msec after the first This attentional blink (AB) occurs under dual-task conditions in which observers are required to report both targets. AB magnitude has been estimated by subtracting the accuracy scores in the dual task from the corresponding scores in a single task in which observers are instructed to ignore the first target. Experiment 1 showed this procedure to be inappropriate, because the first target cannot be ignored. The remaining three experiments elaborated on this finding andrevealed separate endogenous and exogenous sources of the second-target deficit. A parallel was drawn between the AB deficit and the deficit observed in attentional capture. Both types of deficit can be explained on the basis of a hybrid input-filtering model in which endogenous and exogenous factors are subserved by different pathways.