Change Blindness Test: What Are You Not Seeing?
Change blindness is one of the most unsettling findings in attention research: a large, obvious change to a scene can be completely invisible to you if your attention isn't pointed at it. This test uses the classic flicker paradigm — two versions of a scene alternate with a brief blank between them, and one item keeps changing. It usually takes far longer to find than you would expect, and that gap between expectation and reality is the point.
A quiet round of Change Blindness Test — Basic. When you start, everything else fades — just you and the task.
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How to play
- A field of coloured shapes appears, then blanks, then reappears slightly different.
- One item changes colour on every flip. Everything else stays put.
- Tap the item you think is changing. Wrong taps count against you.
- Finish all rounds to see how long each one took you.
Frequently asked questions
What is change blindness?+
The failure to notice a change to a visual scene when the change coincides with a visual disruption — a blink, a cut in a film, or the blank frame used here. Attention has to be on the right place at the right time, and when it isn't, the change simply doesn't register.
Why is there a blank flash between the two versions?+
That blank is what makes the test work. If the two versions swapped directly, the change would create a local motion signal that grabs your attention automatically and you'd spot it instantly. Blanking the whole field creates that signal everywhere at once, which cancels the shortcut and forces you to search deliberately.
Is this the same as a spot the difference game?+
The mechanic is related, but the setup is doing something different. Spot-the-difference shows both images side by side, so it's a comparison task you can work at your own pace. The flicker paradigm never lets you see both at once, so you have to hold one version in mind and check it against the other region by region — which is what exposes change blindness.
Is change blindness the same as change detection?+
No, and the two get confused constantly. Change detection tasks in the Luck & Vogel tradition measure visual working memory capacity — how many items you can hold at once. Change blindness is about attention failing to reach the changing region in the first place. Similar names, different constructs.
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