The Stroop Effect

You might have seen this exercise before in a workbook or museum. You see a list of colors, but each word is also a different color itself. For example, the word “red” might be written in blue font or the word “yellow” might be written in purple font. The exercise says you have to go through the list and say the color of the font, not the word that is written out in front of you.

This isn’t easy! Most people experience a delayed reaction while trying to complete this activity. They are also more likely to get answers wrong than if they simply had to read the words aloud. 

This test is called “The Stroop Test.” The paper describing the test, as well as The Stroop Effect, is one of the most famous papers in the world of psychology. 

What is the Stroop Effect? 

The Stroop Effect is a phenomenon that describes delayed reaction time that occurs when the brain is faced with two different types of stimuli. The process of reading the word and the process of recognizing the color “race” through the brain in order to help us complete the task at hand.

Unfortunately, in the original Stroop test, it is believed that our minds read words faster than they recognize colors. We may flub or accidentally say the word that is on the page, rather than the color of the word, because we read the word first. 

This phenomenon is named after John Ridley Stroop, although some experts say he is not the man who discovered it. Stroop conducted experiments with participants, including the Stroop Test that I mentioned earlier, and shared his findings in 1935. After his experiments showed that participants spent a longer time recognizing color names when they didn’t match up with the words on the screen, psychologists created different versions of the experiment and theorized why this phenomenon exists. 

Reasons Behind the Stroop Effect

There are a few theories as to why we have a hard time recognizing the colors in the Stroop Test.

One common theory is that our brains simply process words faster out of habit. This theory is that of speed of processing theory. It just takes longer to recognize and name colors. 

Another theory has looked at the possibility of parallel distributed processing. When we learn different information, we create pathways in our brain. Some of these pathways are stronger than others. Psychologists believe that the pathways we’ve created to process the meaning of words may be stronger than the ones we’ve created to identify colors. 

Other psychologists say that the delayed response comes from the fact that our brains automatically start to process the meaning of the words in front of us, but doesn’t do the same with the color of the font. This is the automaticity theory. When we see words in front of us, we automatically read them. We don’t do the same when we see colors in front of us. Wouldn’t it be exhausting to look around the room and process and name all of the colors you see in front of you? You don’t look at grass and think “green”, however when you open a book, you say the words in your head. 

Do you think someone who did not know how to read (or did not know how to read in English) would be able to name the colors of the fonts faster?

Yet another theory goes back to a phenomenon that we described in an earlier video. The selective attention theory aims to describe how our brain decides what information is important to pay attention to. When we take in stimuli, we “filter” or “turn down the volume” out the stimuli that does not need our attention at the moment. But what happens when we filter out the wrong information and have to go back and look at the stimuli again? 

Variations of the Stroop Effect

The Stroop Effect continues to be one of the more fascinating and fun phenomena to look at for psychologists young and old. Many psychology students have made tweaks to the original experiment to show how the brain might get confused or work more slowly when faced with similar challenges. 

One of my favorite variations of this experiment is to change the list of words to words that aren’t colors. Examples are the word “microphone” in red font or the word “suitcase” in blue font. The directions are the same: list the colors of the font rather than the word.

This can be even more frustrating than the original Stroop test! 

Get creative and make some of your own versions of the Stroop test. Use different font colors, images, font sizes, or other types of stimuli to trick the brain and stump participants (if only for a moment.) Who knows, maybe you’ll uncover a different side to the Stroop effect that hasn’t been introduced to the world of psychology before!

Theodore T.

Theodore is a professional psychology educator with over 10 years of experience creating educational content on the internet. PracticalPsychology started as a helpful collection of psychological articles to help other students, which has expanded to a Youtube channel with over 2,000,000 subscribers and an online website with 500+ posts.