Abstract
This article proposes a binary Yes/No decision method to measure Stroop and Reverse-Stroop interferences. In the proposition, participants judge whether one given color name (or one given color patch) is consistent or inconsistent with the color (or the word) of an incongruent color-word combination stimulus for each trial of interference conditions, then the degree of interferences is evaluated by the mean response time in interference conditions relative to that in control conditions. This method minimizes the number of color names or color patches given as participant’s choices relative to the well-known matching methods, where four or five choices are given for each trial. Our validation experiment showed that the response time in the interference conditions was significantly longer than that in the control conditions for both Stroop and Reverse-Stroop tasks. These results validated that the Stroop and Reverse-Stroop interferences were measurable by the proposed binary decision methods. Note that the mean response time for Stroop and Reverse-Stroop tasks was equivalent in the test with binary decision methods (in Experiment 1), but that was longer for Stroop tasks than Reverse-Stroop tasks in the test with matching methods (in Experiment 2). These results suggest that the number and area of given participant’s choices affect the difference in response time between the Stroop and Reverse-Stroop tasks.
