Verified by Visual Snow
Visual snow is a neurologic condition in which a person’s vision is altered in several ways, chief among them is seeing innumerable small flickering dots where none exist. Researchers have likened the experience to static, or snow, across the visual field. Additionally, people with visual snow may experience palinopsia or shadow-like images—text from a book or images from a screen—that remain in their field of vision even after looking away. Those with visual snow also often report a heightened sensitivity to light and poor visibility in the dark.
The condition exists on a spectrum of severity. On one end, some find visual snow an annoying disturbance, while those with more severe symptoms may find it life-altering, reducing their ability to work, socialize, and interact with others.
Those who experience visual snow are likely to experience other physical and mental conditions, including tinnitus, migraine, depression, anxiety, depersonalization, and difficulty sleeping.
People can be born with visual snow or they can develop it later in life. Some people born with mild cases of visual snow report that they didn’t realize the world looked differently to other people until adolescence or adulthood. Individuals are born with it in 40 percent of cases. For others, the condition develops in adulthood, usually during a person’s 20s or 30s.
The first study of this condition was published in 1995, and research remains limited.
The physical symptoms of visual snow are more likely to appear in people with severe cases. In addition to the visual static, afterimages, and light sensitivity, migraine can accompany the condition. Research indicates that 50 to 80 percent of people with visual snow also report suffering from migraines. Tinnitus, the constant ringing of the ears, is another common comorbidity for those with visual snow, occurring in as many as 75 percent of patients.
Some researchers have compared tinnitus and visual snow as aural and visual versions of the same experience. Sleep difficulties have also been found to accompany the condition. One study found that 40 percent of those with visual snow tested poorly enough on a sleep quality scale to constitute disordered sleep.
Other symptoms that may accompany visual snow include:
- Poor night vision, also known as night blindness
- The perception of color swirls that often accompany migraines
- Vertigo, feeling dizziness or being off-balance
- Persistent fatigue
Several mental conditions frequently accompany visual snow as well. One study found that 25 percent of people with visual snow experienced severe depression and anxiety, most commonly among those with more severe cases of visual snow. Depersonalization, or the feeling of existing outside one’s body, was reported by 45 percent of participants in another study.
It’s not clear whether these psychiatric symptoms are a result of visual snow or arise from the same neurobiology.
Since people with more severe cases of visual snow are more likely to report psychiatric symptoms, this could result in a diminished quality of life and poor mental health.
Some researchers speculate that psychiatric symptoms may be inherent to the experience of visual snow; levels of depression, anxiety, and depersonalization are experienced with equal frequency among those born with visual snow and those who develop it later in life. People born with the condition may be more likely to see it as a “normal” part of their existence, regardless of severity; those who experience the onset of visual snow later in life are more likely to be shaken or upset by it.
Yes. Studies estimate its prevalence, in some form, at about 2 percent of the population, though the research is limited.
Visual snow appears equally among men and women. Some research finds women may be more likely to have increased severity of the condition along with the symptoms that most frequently occur with it—such as migraine, tinnitus, anxiety, depression, and depersonalization.
The cause or causes of visual snow is unknown. Some are born with the condition and others develop it in adulthood. In a small percentage of cases, traumatic brain injury precedes the symptoms of the condition.
Researchers have identified ADHD as a comorbidity in some cases of visual snow.
The visual distortions of visual snow can resemble the “flashbacks” some experience from taking psychedelic drugs, but they are distinct phenomena. In early research on visual snow, hallucinogenic flashbacks were considered a possible cause of the condition, but researchers have come to believe the two have little or nothing to do with each other.
There is currently no consistently effective treatment for visual snow. Instead, treatment has focused on mitigating the accompanying symptoms.
Medications, like anti-seizure or anti-epileptic drugs, may provide some relief of the symptoms. Tinted glasses that filter out certain colors of light or sunglasses may help with light sensitivity. Transcranial magnetic stimulation, a treatment option for migraine, has been used with mixed results.
Antidepressants and anxiolytic drugs may be prescribed to relieve psychiatric symptoms, and medications have also been prescribed to alleviate poor sleep. Talk therapy, including cognitive behavioral therapy (CBT), can help patients cope. CBT is a frontline treatment for tinnitus, a related condition. A focus on diet, exercise, and other self-care changes can help improve the symptoms of depression and anxiety, as well as poor sleep.
Visual snow is lifelong but not everyone with the condition experiences it all the time. Those with milder presentations may experience it only in certain environments, such as in bright or low light.
