The visual anomaly results from abnormal functioning of portions of the occipital cortex at the back of the brain, not in the eyes nor any component thereof, such as the retinas.

Animated depictions Scintillating scotomas are most commonly caused by cortical spreading depression, a pattern of changes in the behavior of nerves in the brain during a migraine.

[10] While monosodium glutamate (MSG) is frequently reported as a dietary trigger,[11] other scientific studies do not support this claim.

[12] The Framingham Heart Study, published in 1998, surveyed 5,070 people between ages 30 and 62 and found that scintillating scotomas without other symptoms occurred in 1.23% of the group.

Typically the scotoma resolves spontaneously within the stated time frame, leaving no subsequent symptoms, though some report fatigue, nausea, and dizziness as sequelae.

[15] The British physician Hubert Airy coined the term scintillating scotoma for it by 1870; he derived it from the Latin scintilla "spark" and the Ancient Greek skotos "darkness".