Attentional costs and benefits in memory search

The role of attentional mechanisms in memory search was investigated in 2 experiments. In Experiment 1, an abrupt-onset cue was a valid or invalid predictor of a spatially displaced memory probe in a memory search paradigm. The 2 conditions differed only in terms of the duration of the memory probe: either 200 ms or an unlimited duration until the subject's response. We found that memory probe duration had little impact on memory search, as revealed by the slope across memory set size, although an invalid prior cue slowed responding by increasing the intercept by about 70 ms. In Experiment 2, costs and benefits of valid and invalid cues were assessed by inclusion of a neutral condition. Both costs and benefits were found, with effects again localized in the intercept of the memory search functions. A simple model was proposed that estimated 2 attentional transit times, 1 to the abrupt-onset cue and 1 activated after disengagement from an invalid location. We address whether the rapid examination of the contents of working memory should be considered an encapsulated process, unperturbed by abrupt-onset events that delay but do not otherwise disturb the resulting search.