Such scotomas can be part of the aura phase of migraines.

The scintillations were of a zigzag pattern starting in the center of vision, surrounded by a somewhat larger scotoma area with distortion of shapes but otherwise melting into the background similarly to the physiological blind spot. This aura occurred on 2016-01-28, 7pm on a rather busy day.

The progress can be described as 10 minutes of zigzag pattern as shown, followed by 5 minutes with an addition of a waving ribbons coming from left (not shown in picture). In the following 5 minutes, scintillations where only seen peripherally and then disappeared, with another 20 minutes of only scotoma. This was followed by hours of mild left-sided headache.

File usage

It is preferable to use a static image in articles, linking to this flickering animation:

[[File:Scintillating scotoma - play.jpg|link=File:Scintillating zigzag scotoma.gif|thumb|Flickering animation a [[scintillating scotoma]]. The scintillations are of a [[zigzag]] pattern starting in the center of vision, surrounded by a somewhat larger area with distortion of shapes]]

This renders as: