What is the Stroop test actually measuring?
Selective attention — specifically your ability to override the automatic pull to read the word and instead name the ink colour it's printed in. The gap between your reaction time when word and colour match ("congruent") versus clash ("incongruent") is the Stroop effect itself, shown as "interference" after each session.
What's a "commission error" in Go / No-Go?
Tapping when you should have held back — the STOP square appeared and you tapped anyway. It's the classic behavioral marker of impulsivity in cognitive-testing research, distinct from a "miss" (not tapping fast enough on a GO).
Can my scores here tell me if I have ADHD?
No. These are training drills and self-experiments, not the real, professionally administered attention tests (the CPT/TOVA, Conners, clinical Stroop). A slow or impulsive score by itself isn't evidence of ADHD or anything else — treat it as a personal baseline, not a diagnostic signal.
Why do my scores swing so much day to day?
Sleep, caffeine, screen size, touch vs. mouse input, and mood all move the numbers meaningfully. Compare yourself to your own trend over weeks, not to a single session or to anyone else's score.
Where is my history stored?
On this device only, in your browser's local storage — nothing is uploaded anywhere. Each game has its own "Clear history" button if you want to reset it.