Top-down feature-based cueing modulates conflict-specific ERP components in a Stroop-like task with equiprobable conditions

Both attention and interference processing involve the selection of relevant information from incoming signals. Studies already show that interference decreases when the target location is precued correctly using spatial cueing. Complementary, we examine the effect of feature-based attentional cueing on interference processing. We used a design with equal stimulus probabilities where no response preparation was possible in the valid condition due to a response mapping alternation from trial to trial. The color of the Stroop stimuli was precued either validly or invalidly. Electrophysiological data (EEG) from 20 human participants are reported. We expected reduced interference effects with valid cueing for behavioral data and for both Stroop-associated event-related potential (ERP) components (N450 and sustained positive potential; SP). The N450 showed a significant effect for valid trials but no effect in the invalid condition. In contrast, the SP was absent with valid cueing and present with invalid cues. These findings suggest that focused feature-based attention leads to a more effective attentional selectivity. Furthermore, the top-down influence of feature-based attention differentially affects the N450 and SP components.