Individual differences in working memory capacity and the Stroop effect: Do high spans block the words?

The present study examined whether the mechanism that links working memory capacity (WMC) and controlled attention is better construed as suppression of distracting information or as efficient selection of critical information, in the face of distraction. We examined WMC-related differences in the Stroop task, in which participants must ignore word-information and instead name the hue in which a word has been printed. The present Stroop task included several neutral words (i.e., non-color) that were subsequently incorporated in a recognition memory test. Participants were either warned or not warned of this test. High WMC individuals who were warned displayed better memory of neutral words, relative to the no-warning group; suggesting they had actively monitored Stroop-words for relevant information. However, this increased attention to word-content was not associated with increased Stroop interference. We conclude that WMC-related attention is more flexible than early or late selection accounts suggest.