Visual Processing Test

Look at the center of the screen, about 40 cm away. A circle will start flickering slowly, then speed up. Tap "It looks steady now" the moment it stops looking like it's flickering. You'll do this a few times in a row.

Before you start: flickering visuals can trigger discomfort, migraine, or seizures in people sensitive to them, including photosensitive epilepsy. If that applies to you, or you're unsure, skip this test. Stop immediately if you feel unwell.