*Moderate *Not messy *30 minutes
What is the Stroop task?
The Stroop task is a classic psychological experiment that allows us to measure something called “the Stroop effect”. The task measures how word meanings can influence people’s reaction times for responding to visual features like color. In a typical Stroop task, color words like red and green are shown on a screen and participants are asked to name the color that the word is printed in. In congruent trials, the word and the color it is printed in are matching, like this: red. In incongruent trials, the word and the print do not match, like this: red. The table below contains more examples.
The Stroop effect is the difference in reaction time that we find when people respond to congruent vs. incongruent stimuli. Can you guess which stimuli will be named faster?
Materials and Directions:
- This task can be found and completed at this website (scroll down to where it says “Click here to run a demo of the Stroop task”: https://www.psytoolkit.org/lessons/stroop.html
- To keep track of your results, you can download this sheet that we prepared: The Stroop Task Sheet.
- Try doing the task a few times to see how the effect changes as you practice and get better.
- You can also be an experimenter and ask different people to do the task, then observe any differences between your participants.
After the experiment:
How should I interpret my results?
- If your incongruent trials have longer reaction times on average than your congruent trials, you are showing the Stroop effect!
In general, we can understand the Stroop effect as a kind of “interference”: when the word and the color don’t match, the color interferes with your ability to name the word. Why does this interference happen? One way to think of it is that, when you are presented with incongruent words like red where the ink color doesn’t match the word, this initiates a kind of competition in your mind: the word spelling and the ink color are in competition for your attention! The spelling ultimately wins, but because it had to compete with color, you responded slower in incongruent trials like red than in congruent trials like red, where there’s no competition.
We hope this activity has sparked your interest in how psychologists study and understand the complex systems that are our minds. Follow the links below for more information about the Stroop effect, and let us know if you have any questions!
“The Stroop Effect” by Rose Fisher, Simone Luchini, and Yi-Ting Hsueh
References/Further Reading
Stoet, G. (2021, January 27). Stroop effect. psytoolkit.org. https://www.psytoolkit.org/lessons/stroop.html
Stroop effect. (2021, July 4). Wikipedia. Retrieved July 11, 2021, from https://en.wikipedia.org/w/index.php?title=Stroop_effect&oldid=1031893921