Subjects were randomly assigned to three conditions, two of which were exact replications of Experiment 2 conditions: (1) The exo/endo condition with a p = .5 of conflict for both the endogenous and the endogenous task. (2) The exo/endo-noconflict condition with a p = .5 of conflict for the exogenous task, MK-2206 concentration but p = 0 conflict for the endogenous task. In the third, the experimental condition

there was a p = .5 of conflict for the exogenous task and for the post-interruption trials of the endogenous task, but a p = 0 of conflict for the maintenance trials of the endogenous task. Participants were randomly assigned to the three different conditions. We used the same trial exclusion criteria as in the previous experiments. In no condition of the primary task did error rates exceed 3.6% and in no instance did the pattern of error effects counteract the pattern of RTs. Therefore, we again focus only on RTs here, but present error results in Fig. 4. For the interruption task, the mean error rate was 14.45% (SD = 9.69) and the mean RT was 4787 ms (SD = 1761). Fig. 4 shows the pattern of RT and error results for each

of the three conditions as a function of task, interruption (post-interruption vs. maintenance), and conflict. First, note that the pattern for the all-conflict and the exogenous-conflict-only conditions was very similar to the two corresponding conditions in Experiment 1. Thus, we replicated the basic pattern of an interruption-based cost asymmetry that is dependent on experience with conflict in the endogenous task. this website This conclusion is confirmed in the statistical analyses. When comparing the exo/endo and the exo/endo-noconflict group, we found until a highly significant Group × Task × Interruption interaction, F(1, 38) = 8.06, p < .01, MSE = 11288.99, and a significant Group × Task × Interruption × Conflict

interaction, F(1, 38) = 9.68, p < .01, MSE = 2136.51. Regarding the new condition with endogenous-task conflict only for post-interruption trials, we first need to note that RTs in the endogenous, post-interruption, conflict trials were almost 300 ms larger than in the corresponding trials from the exo/endo condition (see also Experiment 2). Likely, this is due to the fact that in this condition, conflict is a rare event that occurs only on post-conflict trials and that therefore is particularly disruptive (e.g., Tzelgov, Henik, & Berger, 1992). We will return to potential implications of this effect below. The most important result for this condition is that the pattern of RTs of task-specific interruption effects was more similar to the exo/endo-noconflict condition than to the exo/endo condition. Note, that this is somewhat obscured by the fact that there were larger task-unspecific post-interruption costs in this group.