Meiran, N. 1 & Hsieh, S. 2
1 Ben-Gurion University of the Negev, Beer-Sheva, Israel
2 National Cheng Kung University, Tainan, Taiwan
Task switching requires maintaining readiness to execute any task of a given set of tasks. However, when tasks switch, the readiness to execute the now-irrelevant task generates interference, as seen in the task rule incongruence effect. Overcoming such interference requires highly fine-tuned inhibition that impairs task readiness only minimally. In experiments involving two object classification tasks and two location classification tasks, the authors show that irrelevant task rules that generate response conflicts are inhibited. This Competitor Rule Suppression (CRS) is seen in response slowing in subsequent trials, when the competing rules become relevant. CRS is shown to operate on specific rules without affecting similar rules and to operate on the competing responses only when generated by the specific competing rule. CRS and backward inhibition, which is another inhibitory phenomenon, produced additive effects on reaction time, suggesting their mutual independence. Using Event Related Potentials, the authors show CRS to operate during the cue epoch, suggesting that it involves the rules rather than the responses. Implications for current formal theories of task switching are discussed.