How to play
The picture flickers between two versions with one difference. Tap the thing that changes. Five rounds, twenty seconds each.
Tap the change
Free in your browser, with ten levels that get harder. No account; your best scores stay on your device.
What the study found
A blink of grey hides big changes.
With a brief blank between two pictures, people needed many alternations to find even large differences. Without the blank they spotted them almost at once.
Rensink, O'Regan and Clark · Psychological Science, 1997
Why it matters
It feels as if you see every detail, but you keep far less than it feels. That is why KOZMO asks about specific behaviours, not for a general verdict.
It is for fun: the game does not measure you.
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