Stimulus-driven Attention and Cognitive Control During Encoding: an Event Related Brain Potentials Study

Stimulus-driven attention drawn to relevant items can improve working memory (WM) whether attentional capture is driven by salient, low level features or by contingent salience from shared features with targets. In the current work, we examined the time course of enhanced attention to contingently salient information in a nonspatial WM task using event related brain potentials (ERPs). In line with previous work, we predicted that the encoding of contingently salient stimuli would be associated with an enhancement of cognitive control processes rather than low-level salience detection. The results of this study supported this hypothesis, evidenced by a posterior P3 component of greater amplitude for contingently salient stimuli relative to stimuli of a control color, which is thought to reflect enhanced attention to information that matches a target held in WM. However, P3 amplitude during encoding was unrelated to subsequent memory accuracy. As an exploratory follow up on these results, we conducted a regression analysis including beliefs about ability to focus attention as a moderator, which interacted with P3 amplitude to predict WM recall of salient letters. Furthermore, source localization analyses implicated a significant contribution of regions in the salience network to the detection of target stimuli, but only frontal control regions showed a greater response to salient than control letters. Thus, the results of this experiment suggest that participants enhance cognitive control during the encoding of contingently salient stimuli, but that the relationship between this neural process during encoding and subsequent benefits to WM recall might depend on individual differences in attentional focus.