Double response to Stroop stimuli.

To reexamine Klein's 1964 findings we carried out two experiments on the double response made to Stroop stimuli. In Exp. 1 incongruent color-word stimuli were presented on a CRT online with a microcomputer. A color-word card was used in Exp. 2. Subjects were asked to read words before naming colors or, conversely, to name colors before reading words. An analysis of variance (the task x the type of task) was performed on response times in both experiments. Two main effects and interactions were nonsignificant. Some subjects made an error-like reverse-order response on the double-response task. The present findings do not support Klein's findings or the competition explanation of the Stroop effect.