game 15 of 16 · measures focus

N-back task (2-back)

Inside TELLS it's “The Letters” — letters flow by. Hit MATCH when one repeats from two steps back.

part of the full 16-game test · about 12 minutes

What the N-back task (2-back) is

Letters stream past; you hit MATCH whenever the current letter repeats the one from two steps back. The n-back task (Kirchner, 1958) is the workhorse of working-memory research — infamous from 'dual n-back' brain-training, and genuinely difficult because the target keeps moving as the stream flows.

What it measures

Hits measure how well you update a memory buffer that's constantly being overwritten; false alarms measure a memory that fires on familiarity instead of position. Both feed focus. A clean 2-back run under speed is rarer than people expect — the stream is designed to blur.

Scattered

Your attention is a butterfly. Details slip the net.

Steady

You hold the thread until something shinier wanders by.

Locked-in

You hold a long sequence in your head and don't drop it.

Why hiring assessments use it

Assessments use n-back to measure working memory in motion — not holding information, but continuously updating it while acting on it, which is most knowledge work in miniature.

TELLS is an independent project — not affiliated with pymetrics, Harver, or any employer's assessment. This is the fun version.