Focus challenge
Reaction time and a color-word attention game. Slower reaction times went with higher death rates.
How to do it
- Sit somewhere quiet. On a computer, rest your fingers on the keys; on a phone, hold it steady.
- Part one: when the box turns green, tap it or press space as fast as you can. Tapping early doesn't count. Five tries make one result.
- Part two: a color's name appears in colored ink. Tap the color of the ink, not the word, or press 1 to 4 or the color's first letter.
- Four practice words come first, then 60 seconds for as many as you can. A wrong answer holds up the next word for a moment.
- If you're color blind, part two may be unfair to you. You can skip it and keep your reaction time.
Your result
Part one: tap the box as soon as it turns green, five times. Part two: name the ink color of each word for 60 seconds, after four practice words.
Nothing you enter leaves this page unless you save your result.
What the research found
Simple reaction time is a basic measure of how fast your brain works. In 5,134 US adults aged 20 to 59, slower reactions went with a higher risk of death. Each step slower (about the gap between an average result and a slow one) went with a 25% higher risk of death, and a 36% higher risk of death from heart disease and stroke. That was after taking age, sex and ethnicity into account. The color-word part is the Stroop task, a common test of attention: naming the ink color takes longer when the word spells a different color. Across 18 studies, that slowdown was bigger in people with Alzheimer's disease, though much of the gap came from slower color naming in general. In a small study of healthy older adults, those who later got Alzheimer's had made more mistakes on the clashing words. Scores improve with practice and change from day to day, and phones and browsers add their own delay. So compare only with your own results on the same device.
Studied in: 5,134 US adults aged 20 to 59 (reaction time); 18 studies of people with and without Alzheimer's disease (the color words).
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- Balota DA et al. Predicting conversion to dementia of the Alzheimer's type in a healthy control sample: the power of errors in Stroop color naming. Psychol Aging. 2010;25(1):208-18. PubMed
- Hedge C, Powell G, Sumner P. The reliability paradox: why robust cognitive tasks do not produce reliable individual differences. Behav Res Methods. 2018;50(3):1166-86. PubMed
- Pronk T et al. Mental chronometry in the pocket? Timing accuracy of web applications on touchscreen and keyboard devices. Behav Res Methods. 2020;52(3):1371-82. PubMed