In the numerical Stroop task, participants are asked to compare the physical sizes (physical task) or numerical values (numerical task) of two digits and ignore the irrelevant dimension. Participants are unable to ignore the irrelevant dimension as indicated by facilitation and interference effects. The literature suggests that there is asymmetry in the ability to adjust control in the physical...

Tasks involving conflict between stimulus dimensions have been shown to activate dorsal anterior cingulate and prefrontal areas. It has been proposed that the dorsal anterior cingulate is involved a domain general process of monitoring conflict, while prefrontal areas are involved in resolving conflict. We examine three tasks that all require people to respond based on one stimulus dimension wh...

In an ERP experiment, we investigated whether a 'permanent' salient distractor changes the deployment of attention to target and nontarget singletons. Observers searched for a color target in a search array that mainly consisted of black vertical lines, but also always contained a line in a task-irrelevant color. Together with this distractor, a target or nontarget singleton was presented. Nont...