Nope. Flicker rate or in some cases, specific patterns. Most of the lights you see nowadays are flickering faster than you can perceive. This boring video will show you how screens set it off.
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My sister developed photosensitive epilepsy during her first pregnancy. It was triggered when she travelled beneath some trees with the sun above them. The speed she was travelling and the density of the branches created the (im)perfect flicker rate.
Know all about it. I have 2 members in my family that suffer with the condition. Also moving images.