Figure 1.

Experimental protocol for Experiments 1, 2 (A) and 3 (B). For Experiment 1 (A), participants responded to the direction of a white, red (depicted) or green go signal arrow. On a subset of trials this was followed after a variable delay by an auditory stop signal which signaled participants to countermand their response. The experiment protocol was the same for Experiment 2 (A), except participants responded to the color of the signal and not the arrow direction. In Experiment 3 (B), participants responded to the direction of a white go signal arrow. On a subset of trials this was followed after a variable delay by a color change from white to either red or green (equal proportions, pseudorandomly interleaved) which signaled participants to countermand their response.