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When 2 targets are embedded in a rapid serial visual presentation stream of distractors, perception of the second target is impaired when the intertarget lag is relatively short (less than 500 ms). Stimuli concurrently presented with the stream can affect this phenomenon, which is called attentional blink (AB). Previous studies have yielded conflicting results concerning the direction of the effect of added distractors on the AB: Some studies report an increased AB, whereas others report a decreased AB. The present study explored the boundary conditions of the exaggeration-reduction effects of distractors on the AB and investigated underlying mechanisms by manipulating the spatial configuration, timing, and type of distractors. The results indicate that the magnitude of the AB deficit increased, regardless of the type of distractors, when spatial uncertainty of the target locations was involved. The reduction of the AB occurred at optimal presentation of distractors and disappeared when the second target was presented at a suprathreshold level. These results suggest that stochastic resonance or the center-surround attentional mechanism may contribute to the reduction effect of distractors on the AB deficit. [ABSTRACT FROM AUTHOR]

Abstract: When two visual targets are presented in rapid succession, perception of the second target is deteriorated if the temporal lag between the two targets is short (0–300 ms). This ‘attentional blink’ (AB) phenomenon has been believed to occur only when the second target is followed by a backward mask or when there is a task switching between two targets. The present study revealed another determining factor for the occurrence of the AB, the presence or absence of a distractor stream. Five experiments examined the effect of possible confounding factors in the extant literature and suggested that the mere presence of a distractor stream affects the processing of targets even when the observers tried to ignore them, resulting in a processing delay. This effect is discussed in a model of AB deficit in terms of decay of the second target's representation. [ABSTRACT FROM AUTHOR]