ERPs dissociate the effects of switching task sets and task cues.

Recent studies have suggested that reaction time (RT) costs associated with switching tasks do not reflect an endogenous control process of task set reconfiguration [Logan, G. D., Bundesen, C., 2003. Clever Homunculus: Is There an Endogenous Act of Control in the Explicit Task-Cuing Procedure? J. Exp. Psychol. Hum. Percept. Perform. 29 (3), 575-599]. Participants randomly switched between two simple tasks. Task was cued 600 ms prior to stimulus presentation using either a color or shape cue. A significant RT task switch cost was found when controlling for either a repeat or switch in cue category. In comparison, a switch in cue category had no effect on RT, even when examined across a cumulative distribution. Electrophysiological data revealed early cue processing effects within the first 300 ms after cue onset. However, replicating previous findings, an increased parietal positivity was found for task switch relative to task repeat trials that emerged prior to stimulus onset. This suggests that task set reconfiguration processes are activated when switching between tasks and supports the usefulness of task-switching paradigms in investigating cognitive control processes.