Don't Blink
Change Detection Assessment
Something will change — tap the instant you notice
10 rounds · color, number & shape · gets more subtle each round
01 /How to Play
- An object will appear on screen — stare at it without blinking.
- At a random moment between 1–4 seconds, something will subtly change.
- Click or tap the instant you notice the change.
- If you miss it, the round counts as a miss — you get 10 rounds total.
- Your score combines average reaction speed and detection accuracy.
02 /The Science
Change blindness — the failure to detect visual changes that occur during brief interruptions — is one of the most striking demonstrations of the limits of human visual attention. Even large changes can go unnoticed when attention is divided or misdirected. The phenomenon reveals that visual perception is not a passive recording of the scene but an active, attention-dependent process. The superior colliculus and V5/MT area of the visual cortex are responsible for detecting motion and change signals, but these signals only reach conscious awareness when top-down attention from the prefrontal cortex is directed to the relevant location. This test specifically measures the efficiency of that attentional spotlight.
03 /Pro Tips
- Fixate on the center of the object — do not let your gaze drift.
- Blink as little as possible — the change may occur during a blink.
- Broaden your attentional focus rather than fixating on one feature.
- Changes are always in one of three domains: color, number, or position.
- At higher rounds, changes become extremely subtle — trust your gut rather than deliberating.