Flanker Test: Can You Read Just the Middle Arrow?
The Eriksen flanker task is the cleanest way to measure how well you can narrow attention to one spot. Five arrows appear in a row and only the middle one matters — but the four flanking it point the same way, the opposite way, or nowhere at all, and your answer gets slower and less accurate when they disagree. That slowdown is the flanker effect, and this test measures yours. Free to play, scored instantly, no sign-up required.
A quiet round of Flanker Test — Standard. When you start, everything else fades — just you and the task.
No sign-up needed. Press Esc to exit anytime.
Tip
Be narrow before the arrows arrive. Attention takes time to tighten, and all five arrows appear at once — so a trial spent getting narrow is a trial the flankers had a head start on. Resting your gaze on the exact spot where the center arrow will land means each trial begins narrow instead of ending that way.
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Flanker Test: what it is and where it comes from
What is the Eriksen flanker task? The Eriksen flanker task (Eriksen & Eriksen, 1974) measures interference control: you report the direction of a central arrow while ignoring the arrows on either side of it. Responses slow down, and errors rise, when the flankers point the other way. Focani's free browser version runs 24 trials per session and needs no sign-up.
| Specification | Flanker Test |
|---|---|
| Primary cognitive domain | Interference control — in the “Holding a rule under pressure” group |
| Original citation | Eriksen, B. A., & Eriksen, C. W. (1974). Effects of noise letters upon the identification of a target letter in a nonsearch task. Perception & Psychophysics, 16(1), 143–149.doi:10.3758/BF03203267 |
| Core dependent metrics | Mean reaction time (ms) · Reaction-time variability (SD, ms) · Congruent vs. incongruent reaction time (ms) · Shortest accurate response window (adaptive tier, ms) |
| Standard stimulus / trial parameters | Letters as flankers, with trial counts running into the hundreds so each congruency condition gets enough trials. |
| This version | Standard — 24 trials · Extended — 40 trials · Adaptive — 40 trials |
| Browser adaptation notes | Arrows rather than letters, and a fraction of the trials per condition. A single session's congruency effect is noisy — usually in the right direction, not stable in magnitude. |
Full sources for every test, and what each version changes, are on the instructors page.
How to play
- A row of five arrows appears. Only the center one carries the answer.
- Press ← or → for the direction the MIDDLE arrow points — or tap the buttons.
- The four around it are noise — sometimes helpful, sometimes actively wrong.
- Finish all trials to see your accuracy and your flanker effect — the milliseconds the conflicting arrows cost you.
Flanker Test tips
Ways to play it better — each one comes from how this version actually scores, not from general advice about concentration.
Be narrow before the arrows arrive
Attention takes time to tighten, and all five arrows appear at once — so a trial spent getting narrow is a trial the flankers had a head start on. Resting your gaze on the exact spot where the center arrow will land means each trial begins narrow instead of ending that way.
You cannot suppress them, only out-focus them
The four outer arrows fall inside the attentional window whatever you intend — that is the finding this task exists to demonstrate. Trying not to see them adds effort without adding accuracy; making the window smaller is the lever that actually moves.
Spend the extra care only where it buys something
Errors concentrate on the trials where the flankers disagree with the center. A blanket slowdown pays that cost on every trial including the easy ones; a single extra beat when the row looks conflicting pays it only where it is doing work.
One caveat worth knowing: a change of strategy moves your score for reasons that have nothing to do with attention. Your dashboard reads each session against your own recent ones, so if you adopt something from this list, give it a few sessions before reading anything into the trend.
Frequently asked questions
What is the flanker test?+
A task from attention research, introduced by Eriksen and Eriksen in 1974. You respond to a central target while irrelevant items flank it. When the flankers point the opposite way, responses slow down — showing that attention cannot be narrowed perfectly to a single location, so nearby items get processed whether you want them to or not.
What does the flanker effect measure?+
How much irrelevant information from around your target leaks into your response. A smaller flanker effect means you filtered the surroundings out more successfully on that run. It moves with fatigue and practice, so treat one session as a snapshot rather than a fixed trait.
Why are some trials just dashes?+
Those are neutral trials, and they are the baseline the other two conditions get measured against. Without them you cannot tell whether matching flankers sped you up or conflicting flankers slowed you down — the gap between congruent and incongruent alone can't separate the two.
How is the flanker test different from the Stroop test?+
Both create conflict, but in different places. In the Stroop test the conflict is inside a single stimulus — the word fights the ink color. In the flanker task the target is completely unambiguous; the conflict comes from other items sitting next to it. So Stroop stresses suppressing an automatic process, while the flanker task stresses narrowing attention in space.
Where this fits
- Attention Span Test — Conflict a third time, now purely spatial. The center arrow is perfectly clear; the four crowding it are not part of the question, and they slow you down anyway.
Related attention paradigms
Holding a rule under pressure — closest to this one
- Stroop Test — practices and measures selective attention and mental control.
- Simon Effect Test — practices and measures response conflict and inhibitory control.
- Go/No-Go Task — practices and measures inhibitory control and impulse braking.