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The Stroop task (named after J. Ridley Stroop, 1935) has been one of the most widely studied attentional tasks in psychology, yet researchers continue to debate the origin of this effect. Briefly, the Stroop effect is the finding that people are slower to identify the color a word is written in when the color and word are incongruent (e.g. BLUE written in red ink: BLUE) compared to a neutral situation (e.g. UELB written in red ink: UELB), and are faster when the color and word are congruent (e.g. RED written in red ink: RED) compared to neutral. The slowdown from an incongruent word has been termed Stroop interference while the speedup from a congruent word has been termed Stroop facilitation. In general, many researchers suggest that Stroop interference occurs because people automatically read the word despite their intentions, leading to an incongruent response. After reviewing several hundred Stroop experiments, MacLeod (1991) argues that Stroop facilitation is artifactual (MacLeod & MacDonald 1995; MacDonald & MacLeod 1996). Others, however maintain that Stroop facilitation is not artifactual (Cohen, Dunbar, & McClelland, 1990). Some of our current research is designed to test these claims. Can you name the colors faster in list 1 or list 2? (time yourself!)

Some Related Publications

Kahan, T. A., & Hely, C. D. (2008). The role of valence and frequency in the emotional Stroop task. Psychonomic Bulletin & Review, 15, 956-960.

Neely, J. H., & Kahan, T. A. (2001). Is semantic activation automatic? A critical re-evaluation. In H. L. Roediger, J. S. Nairne, & A. M. Surprenant (Eds.), The nature of remembering: Essays in honor of Robert G. Crowder (pp. 69-93). Washington, D. C.: American Psychological Association.