Effects of conflict in cognitive control: Evidence from mouse tracking.

It has long been debated whether the "congruency sequence effect (CSE)" in conflict tasks such as Flanker could reflect adaptive control. The current study used "mouse tracking" to tackle the issue in a combination of three conflict tasks (i.e., Flanker, Simon, and Spatial Stroop tasks). Congruency effects from previous and current trials emerged in latencies as well as curvature of movement trajectories in all three tasks. Critically, movement initiation times were affected only by congruency on previous but not on current trials. A further analysis showed that even when initiation time on the previous trials was taken into account, a subtle but highly significant effect of conflict arising from trial -1 on initiation times remained. Although not necessarily implying "conflict adaptation," i.e., a dynamic up- and downregulation of cognitive control in response to a recent conflict, our finding indicates a specific sensitivity to the presence or absence of recent "conflict" in the cognitive environment.