Global Mind Tests

N-back (2-back)

Working-memory updating under interference: press when the current letter matches the one from two steps earlier.

0/30
Trials
Accuracy
Score (0–100)
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A

Rule: press only when the current letter matches the letter shown two steps earlier. Your score (0–100) blends accuracy with speed on correct hits.

Tip: keep your eyes on the center and use steady breathing. Fast but sloppy attempts usually reduce the final score.

How to interpret your 2-back score

The 2-back task is widely used in cognitive psychology because it forces continuous updating: each new stimulus shifts what is relevant (two positions back) and what must be ignored (the most recent item). This makes it a practical way to self-track short-term mental control under mild time pressure.

What the score means

How to use this test for self-tracking

Common pitfalls

FAQ

Is this an IQ test or a medical diagnostic?

No. This is a simple cognitive task for self-tracking and comparison. It does not diagnose any condition and should not be used for medical decisions.

Why can my score vary from day to day?

Working memory and attention are sensitive to sleep, stress, caffeine, distractions, and motivation. Compare averages across multiple sessions, not a single attempt.

What’s the difference between misses and false alarms?

A miss is failing to press on a true 2-back target. A false alarm is pressing on a non-target. False alarms often indicate impulsive responding or confusing 1-back with 2-back.

Why use letters (and not numbers or shapes)?

Letters are easy to perceive and label quickly. The task aims to measure updating and interference control rather than visual search difficulty.

How are results saved?

Your history is saved locally in your browser. The score is also saved in the shared store (“Your results”).

Can I improve with practice?

You can often improve consistency and reduce mistakes with short, regular practice. Improvements are usually gradual, so weekly trends are more meaningful than day-to-day fluctuations.

Privacy note

This page stores your results in your browser to show history and trends.