Visual snow, also known as visual static, is an uncommon neurological condition in which the affected individuals see white or black dots or transparent dots in part or the whole of their visual fields. The condition is typically always present and can last years. Migraine and tinnitus are common comorbidities and are both associated with a more severe presentation of the syndrome.

The cause of visual snow is unclear. The underlying mechanism is believed to involve excessive excitability of neurons in the right lingual gyrus and left cerebellar anterior lobe of the brain. Research has been limited because of issues of case identification and diagnosis, the latter now largely addressed, and the limited size of any studied cohort. Initial functional brain imaging research suggests visual snow is a brain disorder.

There is no established treatment for visual snow. Medications that may be used to treat the condition include lamotrigine, acetazolamide, or verapamil. However, these do not commonly result in benefits and the evidence for their use is very limited.