Overview of Visual Snow Syndrome

>  Overview of Visual Snow Syndrome

Information About VSS

What is Visual Snow Syndrome?

Visual Snow Syndrome (VSS) is a neurological disorder that impacts an individual’s vision, hearing, cognition, sensory processing, and quality of life. The brain of an individual with VSS processes visual information abnormally, as well as other sensory information. Visual Snow (VS), is the primary symptom of the condition of which it is also named after. VS entails seeing snow-like static throughout the entire visual field (with your eyes open and closed). However, the condition also encompasses an array of other debilitating visual and non-visual symptoms. VSS symptoms impact an estimated 2-3% of the world’s population. People of all ages and backgrounds worldwide are affected by VSS daily. Some experience symptoms since birth while others experience the sudden onset of the condition.

Researchers have identified measurable differences in the brains of those with VSS. They have increased metabolic activity, especially in areas involved in visual perception and processing. VSS is linked to abnormalities in serotoninergic (serotonin) and glutamatergic (glutamate) neurotransmission. Factors that impact the nervous system and induce neurotransmitter alterations, neuroplasticity, or structural and functional changes within the brain have the potential to affect the intensity of VSS symptoms. Data has also shown that VSS symptoms are not a manifestation of anxiety and depression; instead, the debilitating nature of these symptoms coupled with the medical community’s historic marginalization, misdiagnosis, and mistreatment of VSS patients can have a profound, devastating impact on their mental health.

Evidence has now proven that VSS is a legitimate and distinct neurological condition that entails both visual and non-visual symptoms. As more information about the condition is discovered and reports of VSS continue to rise, it is gaining increased medical and scientific recognition globally.

Additional awareness, education, resources, and research are needed to help the millions of people who are affected by VSS. Collective advocacy efforts will allow the world to become more informed about the condition, ensuring a timely diagnosis for patients, increased support, further understanding regarding VSS, continued treatment development, and a potential cure for the disorder.

For more information about VSS, please review the sections and resources below.

Symptoms of VSS

The primary symptom of VSS is seeing visual snow, which can be described as seeing static, flickering dots, and flashing lights 24/7 (with your eyes open and closed). Some describe it as trying to see in the middle of a snowstorm or through a snow globe that has been shaken up. However, VSS entails more than just seeing visual snow. People with VSS also commonly experience many other debilitating visual and non-visual symptoms, such as palinopsia, photophobia, tinnitus, paresthesia, anxiety, depression, depersonalization, and insomnia. The intensity, appearance, and degree of impact of these symptoms range from mild to moderate to life-altering, depending on the person.

Learn more about VSS

 Please use the following link to access our Diagnostic Criteria for Visual Snow Syndrome (to share with your doctor, etc.), as well as a more comprehensive list of symptoms with photo references.

Causes of VSS

The exact cause of VSS is still unknown. The first documented cases of visual snow/static vision were reported in 1944. Today, the origin of VSS has been linked to hyperactivity in the visual cortex (lingual gyrus) of the brain, abnormalities in the visual processing centers of the brain, and alterations in the neural signals between the eyes and brain. Research has also demonstrated cortical hyper-reactivity in visual brain areas, indicating a network disorder rather than a focal pathology. Imaging studies (7-Tesla MRI and FDG-PET/MRI) have also shown microstructural and functional connectivity differences in cortical and thalamic regions. Possible biomarkers of VSS have been discovered: abnormalities in glutamatergic and serotoninergic neurotransmission.

A recent study, supported by the Visual Snow Initiative, discovered the first-ever possible biological basis of VSS, revealing that the patterns of activity in two brain chemical systems, glutamate and serotonin, are different in people with VSS compared to those without the condition. Research into the causes of VSS, its pathophysiology, and further treatment options is ongoing and increasing day by day.

Latest News & Research

Here, our team will share the latest news and updates regarding the Visual Snow Initiative, research studies, interviews, projects, as well as any additional information related to our global efforts to better understand, treat, and/or cure Visual Snow Syndrome.

Diagnosing VSS

Historically, it has been challenging for people with VSS to receive an accurate diagnosis.

VSS is diagnosed based on a patient’s symptoms and a thorough clinical evaluation, including a comprehensive medical history and a comprehensive eye exam to rule out eye-related conditions. (Optometric and ophthalmological examinations typically yield “normal” results.) In some cases, an MRI or EEG may be ordered to rule out other neurological conditions.

Neuro-ophthalmologists and neurologists are best equipped to address VSS, including some ophthalmologists, optometrists, neuro-optometrists, and vision therapists who are trained in the management/treatment of VSS symptoms. 

The types of physicians involved in VSS include:

  • Neuro-ophthalmologist: Doctor with expertise in both neurology and ophthalmology, addressing visual issues linked to the nervous system
  • Neurologist: Doctor specializing in the diagnosis and treatment of brain, spinal cord, and nervous system disorders
  • Ophthalmologist: Doctor specializing in eye care, diagnosing and treating various eye conditions and performing surgeries
  • Neuro-optometrist: Vision care professional trained in neurology and optometry, focusing on vision problems related to neurological conditions
  • Optometrist: Vision care professional specializing in visual exams, corrective lenses, and managing common eye conditions


If you suspect you may have VSS, you can refer your doctor to our Diagnostic Criteria.

It can sometimes be difficult to find medical professionals who understand or specialize in VSS. VSI also has a list of physicians from around the world with knowledge of VSS that can help with diagnosis and treatment options. For more information, please see our Physicians & Specialists Directory.

Be Part of the Solution

Support Visual Snow Syndrome Research

All donations to the Visual Snow Initiative go directly to Visual Snow Syndrome (VSS) research.

Your tax-deductible contribution ensures that global research will continue and makes a positive difference in the lives of people affected by VSS.