Seeing Science: Exploring Perception with the Stroop Effect
Have you ever tried to pat your head with one hand while you rub your stomach with the other? This science activity is kind of like doing that, but it can actually give you some insight into how your mind works. The challenge of this activity is to name colors. It sounds simple enough, right? If you think it does, you should see what happens when words of colors get in the way! This is a fun activity to try out with family and/or friends while spending time together over the holidays.
This activity is not appropriate for use as a science fair project. Good science fair projects have a stronger focus on controlling variables, taking accurate measurements, and analyzing data. To find a science fair project that is just right for you, browse our library of over 1,200 Science Fair Project Ideas or use the Topic Selection Wizard to get a personalized project recommendation.
This activity is an attempt to unravel the workings of thought processes that involve attention, perception, reading and naming. How does it work? It is an investigation into a phenomenon known as the Stroop effect. In 1935, this phenomenon was first described in a now-famous experimental psychology paper by John Ridley Stroop. The Stroop effect uses words printed in different colors of ink (such as red, green or blue) and shows how when those printed words are also the words of colors, it can affect how quickly a person is able name the color of the ink. For example, if the word “red” is printed in yellow ink it will take a different amount of time for a person to name the color of the ink than if the word “red” is printed in red ink. What is the difference exactly in the time that it takes to say the ink color? Try this activity with some friends and/or family to find out!
Extra: You could try this activity again but this time use cards with words written on them in matching ink compared to cards with color words written on them all in black ink. Do you find a difference in how easily people can read the color words based on the whether they’re written in matching ink or only black ink?
Extra: Repeat this activity but this time have people look at so that the words are upside-down. Is there still a Stroop effect when the cards are used upside-down?
Extra: Another way to investigate the Stroop effect would be to test it on some youngsters who know their colors but don’t yet know how to read. What do you find when testing the Stroop effect with this specific group?
Observations and Results
Did you find that people could more quickly go through the set of cards with the words written in matching ink compared to words that were written in a different colored ink?
The Stroop effect shows that when a color word is printed in the same color as the word, people can name the color of the ink used more quickly compared to when a color word is printed with an ink color that is different from the word. (For example, when blue ink is used to write the word “blue,” the ink color is named more quickly than when blue ink is used to write the word “green.”) This is what you should have also seen when doing this activity. For example, you may have seen that it took volunteers around 13-17 seconds to get through the matching set of cards, but around 20-25 seconds to get through the non-matching set.
One explanation for the Stroop effect is called interference. From the earliest years of school, reading is a task that people practice every day. We become so good at it that we read words automatically. When we are asked to name the color of the word instead of reading the word, somehow the automatic reading of the word interferes with naming the color of the word. This interference effect provides scientists with a measurable means to investigate how the brain works.
More to Explore
Teisha Rowland, PhD, Science Buddies
Science Buddies |
Psychology, reading, colors, perception, reaction time
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