The causes are unclear. The underlying mechanism is believed to involve excessive excitability of neurons within the cortex of the brain, specifically the right lingual gyrus and left cerebellar anterior lobe of the brain. Persisting<unk>  can feature as a leading addition to a migraine complication called persistent aura without infarction, commonly referred to as persistent migraine aura (PMA). In other clinical sub-forms of migraine headache may be absent and the migraine aura may not take the typical form of the zigzagged fortification spectrum (scintillating scotoma), but manifests with a large variety of focal neurological symptoms.<unk>  does not depend on the effect of psychotropic substances on the brain. Hallucinogen persisting perception disorder (HPPD), a condition caused by hallucinogenic drug use, is sometimes linked to<unk> , but both the connection of<unk>  to HPPD and the cause and prevalence of HPPD is disputed. Most of the evidence for both is generally anecdotal, and subject to spotlight fallacy. Another proposed mechanism is a thalamocortical dysrhythmia of the<unk>  pathway, similar to tinnitus, which is a thalamocortical dysrhythmia of the auditory pathway.
Visual snow
Persistent aura without infarction
Instrument myopia
Aura (symptom)
Dental plaque
Pattern glare
Airsickness
Suberosis