The Stroop effect is a phenomenon where it takes longer to name a word’s colour when the text colour doesn’t match the word. It’s a fun way to learn how your brain works.
Try saying the colours of the words below. Does the second line take longer? This is the Stroop Effect in action. Our brains read automatically, so when the word and colour aren’t the same, it causes a slight slowing of the thought process.
This simple investigation comes with a free Stroop effect worksheet, so all you need is a willing volunteer to help!
Are you ready to test your brain?
Stroop Test Investigation
You’ll need
Instructions
Record how long it takes to read the words for the colours out loud ( box 1 ). Repeat 3 times.
Record how long it takes to say the colour of the word out loud ( box 2 ). Repeat 3 times.
What’s going on?
The Stroop Effect is named after John Ridley Stroop, who discovered the strange phenomenon in the 1930s. You probably found that it took you longer to name the colour the word was written in rather than reading the word. This is because the words interfere with your brain’s ability to name the colour. There are two theories to explain why this happens.
The Speed of Processing Theory
This says that the interference happens as words are read faster than colours are named.
The Selective Attention Theory
This says that the interference occurs as naming colours requires more attention than reading words.
Extension Tasks – Stroop Effect
Try reading the words upside down.
Create a test using non-colour words written in different colours.
Colour just the first letter of a word with the incorrect colour.
Repeat the experiment with a young child ( who can read ) and an adult.
More colour science experiments
Find out if colour affects temperature with a simple STEM challenge using ice.
Learn about colour theory with squishy bags.
Neuroscience activities for kids
Make a model brain with playdough.
Learn about neurons with a neuron cell model.
Test your reaction time with a ruler.
Take a look at a 3D brain model.
Science Concepts
Brain
Neurology
Psychology
Last Updated on February 7, 2025 by Emma Vanstone
