When similarity leads to sparing: probing mechanisms underlying the attentional blink

When two targets are embedded in a temporal stream of distractors, second-target identification is initially impaired and then gradually improves as inter-target interval lengthens (attentional blink; AB). Notably, in about half of the published studies, this deficit is partially ameliorated when the targets follow one another directly, a condition known as "lag-1 sparing". Here, we probe the impact of target-distractor similarity on lag-1 sparing, with the surprising finding that while high similarity impairs second-target accuracy at all subsequent lags, it actually improves accuracy when the targets follow one another directly. We suggest that this improvement reflects the positive influence of over-committing resources to target processing in the AB.