Batteries not required.
It's trickier than it looks.
Our entire visual field is not made the same.
It’s all thanks to the Ebbinghaus illusion.
The pigments morph because of the Munker-White illusion.
But you'd be forgiven for thinking otherwise.
The treadmill works out your brain, too.
Time is subjective.
Do you pass out when you get your blood drawn? You're not the only one.
We still don’t understand why we see the particular images we do.
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