Visual Snow Syndrome

The goal of this study is to learn more about the brain pathways and activity involved in creating Visual Snow Syndrome (VSS). The main questions it aims to answer are: * Does VSS arise from spontaneous activity in brain pathways? * Where in the brain does the activity contributing to VSS arise? * How does brain activity contribute to VSS? Participants will: 1. Undergo assessments and questionnaires to understand visual and mental symptoms, cognitive, and sensory function. 2. Make visual judgements based on images presented to them both inside and outside a magnetic resonance imaging (MRI) machine. 3. Undergo scanning of their brain while inside of an MRI machine.

In this project, the aim is to recruit patients with drug resistant epilepsy and those suffering from migraine. Interestingly, patients suffering from epilepsy are also more often reporting to suffer from migraine. The pathobiology is understudied, but it is believed that both etiologies results from brain networks changes. A clinical certified 7T Terra Siemens scanner will be employed to assess in all participants (including healthy controls) how the microstructure differs in disease specific areas. Patients will further be clinically assessed as well as undergo questionnaires. Migraine is also a common comorbidity to visual snow syndrom and has been shown to impact similar brain regions. However, the pathophysiology is still understudied and a better understanding of the two diseases is needed.

The purpose of this basic science study is to better understand human visual perception. Phosphenes are flashes of light that can be induced using Transcranial Magnetic Stimulation (TMS). The location of these phosphenes is known to change with eye movements, but the exact influence of these movements is not fully understood. The main questions this study aims to answer are: How does stimulating specific areas of the visual cortex relate to where a person perceives a phosphene? How do eye movements affect the accuracy of mapping these sensations? The study will enroll three groups of adults (aged 18-65): patients with Visual Snow Syndrome, color-blind participants, and healthy volunteers. During the experiment, participants will receive single-pulse TMS to their visual cortex. Simultaneously, their eye movements will be monitored with an eye-tracker, and their brain activity will be recorded with EEG. Participants will be asked to report the location of the perceived light flashes. This will help create a map of the brain areas responsible for visual sensations and clarify how eye movements influence this process.

Visual Snow Syndrome (VSS) is a neurological condition with bran network dysregulation involving the visual pathway. This is a research trial comparing the effect of an 8-week mindfulness-based intervention via a group-learning course, the MBCT-vision programme, to treat Visual Snow Syndrome, compared to people on a standard care (wait-list control). Participants will be randomly allocated to either the Treatment group (MBCT-vision), or the Control group (wait-list control). After a waiting period, people allocated to the Control group will also be offered the MBCT-vision treatment. The primary outcome is to compare the severity of the visual symptoms on a 0 to 10 scale between the two groups.