Electronic Accessibility

Last updated: 5/26/2025

The Stroop Color and Word Test, often shortened to "Stroop test," serves as a good example of an activity that cannot be made fully accessible due to the nature of the activity.

The test was originally conceived in the 1930s as a means for demonstrating and quantifying the "Stroop effect," a mental processing delay that occurs when one encounters incongruent stimuli. In its most common form, the test has you observe/read words that are presented in different colors and announce the color. For example, with the first word below, you would say "red" but with the second word, you would say "green," even though the word itself is "purple."

This Stroop test demonstration allows you to try the Stroop test yourself and explore some of the accessibility and accommodation techniques discussed later in this page.

Test takers typically find that they announce each color more quickly when it matches its word — like "red" in the example above — and that there's a greater delay in announcing a color when its word is a different color, like the green "purple" example above.

Since the Stroop test fundamentally involves the perception of stimuli — that is, it's not possible to experience or demonstrate the Stroop effect without relying on the perception of stimuli — it's an activity that cannot be fully accessible due to its inherent nature; it will always leave out, or provide a less equivalent experience for, certain individuals who perceive stimuli differently.

What to do in such a situation?

First, try to make the activity as accessible as you can.

For instance, with the Stroop test, you could assign each word alt text that conveys the word and its color: like, "'red' set in red" and "'purple' set in green". This approach wouldn't provide as equivalent an experience for screen reader users as you can create in other situations involving alt text, but it would provide some means of having learners process incongruent stimuli — it'd just be stimuli they read instead of saw — and as long as you were consistent in your alt text approach across the activity's three rounds, screen reader users should experience similar results: that is, they should find that it takes them longer to announce the correct color in the "'purple' set in green" round versus the "'red' set in red" round.

Second, you should explore if alternative versions that don't rely on the same abilities are possible. For example, the Stroop Color and Word test relies both on one's ability to perceive visual stimuli and on one's ability to differentiate colors. Would it be possible to create and offer a version of the Test that didn't rely on one's ability to differentiate colors? Well, that's what the Stroop test demonstration seeks to do with its number, position and animal variations — all still rely on one's ability to perceive visual stimuli, but at least they negate the need to differentiate color.

And with the Stroop Audio version, you can experience a variation that also eliminates reliance on one's ability to perceive any visual stimuli (though, it does so by shifting reliance to one's ability to perceive auditory stimuli).