So-called "movement phosphenes" are known to follow any side-to-side movement of the eye. The imagery will fade eventually, but may still repeat itself after a brief period of rest.

How long do phosphenes last?

Visual changes known as auras are a common symptom of migraine headaches. An aura typically lasts about 20 to 30 minutes and then goes away on its own, without any treatment.

Is it normal to see phosphenes all the time?

But the phosphenes we mostly see every day are not related to any type of electromagnetic stimulation. Instead, most phosphenes occur spontaneously when the atoms in our eyes exchange their biophotons. You can also trigger phosphenes yourself by applying pressure to your eyes — but be careful trying this at home!