Coloring single Stroop elements: Reducing automaticity or slowing color processing?

Automaticity theory and the effect of coloring a single element were tested with all or only 1 element colored in Stroop tasks. The 312 participants in 5 experiments indicated stimulus presentation color by key press. Experiments 1 and 2 replicated those of D. Besner, J. A. Stoltz, and C. Boutilier (1997) with some changes, and revealed similar results: less Stroop interference with only 1 letter colored. Besner et al. (1997) interpreted the results as indicating that coloring a single letter eliminates automatic reading processes. The cause of that reduction in Stroop interference was investigated in Experiments 3, 4, and 5 using color words, bars, and rectangles. The effect of coloring 1 element was to increase color-naming time by the same amount for congruent and neutral, nonverbal stimuli, but not for incongruent stimuli. The results are interpreted in terms of automaticity theory, and a continuous flow approach to the Stroop effect is presented.