Such a silly little exercise this. You’ve probably done it many times.

Look at the words below and say the colour of the font (don’t say the word, just the colour of the font)

It may be silly, but it’s not easy. It’s called the Stroop Effect and according to Wikipedia, it’s named after John Ridley Stroop, who first published the effect in English in 1935 (it had been published originally in Germany in 1929).

In psychology, the Stroop effect is a demonstration of interference in the reaction time of a task. When the name of a colour (e.g., “blue”, “green”, or “red”) is printed in a colour that is not denoted by the name (e.g., the word “red” printed in blue ink instead of red ink), naming the colour of the word takes longer and is more prone to errors than when the colour of the ink matches the name of the colour.

I ended up going on a bit of a journey of discovery, and simplistically, while there are a few theories out there describing why you struggle to easily do the exercise, the most common one is:

The brain can’t help but read. As habitual readers, we encounter and comprehend words on such a persistent basis that the reading occurs almost effortlessly, whereas declaration of a colour requires more cognitive effort. When there is a conflict between these two sources of information, our cognitive load is increased, and our brains have to work harder to resolve the required difference. Performing these tasks (preventing reading, processing word colour, and resolving information conflict) ultimately slows down our responses, and makes the task take longer.

If you do the exercise again with the image below (assuming you don’t read German) you’ll find you get through the words far quicker and without your brain going into high speed processing mode (I could feel mine working overtime in the first exercise)

It’s easier because the conflict between identifying words and processing colour is lessened. Except when you get to ‘Pink’, where the conflict increased for me 🙂

What seemed like a next obvious question, was whether practicing this test might have any impact on my brain? While the Stroop Test is used in many ‘Train Your Brain’ games, what I discovered was inconclusive.

So I made one up (you can download it below if you’d like to play), printed it out and have stuck it on my bathroom mirror. I’m gonna run through it while brushing my teeth, which happens twice a day, and see if anything is different after a week or 10 days?


Download the Stroop Effect here