A newly published case report explored whether repetitive transcranial magnetic stimulation, known as rTMS, could help reduce symptoms of Visual Snow Syndrome (VSS). The researchers also examined whether treatment was associated with measurable changes in the participant’s brain activity. Although the study involved only one participant, it offers new insight into how non-invasive brain stimulation may influence the brain networks associated with VSS.
What Is Transcranial Magnetic Stimulation?
Transcranial magnetic stimulation, or TMS, is a non-invasive technique that uses magnetic pulses to influence electrical activity in targeted areas of the brain. During treatment, a magnetic coil is placed against the scalp and delivers brief pulses that pass through the skull without surgery or implanted devices.
When these pulses are delivered repeatedly, the technique is called repetitive transcranial magnetic stimulation, or rTMS. Depending on how quickly the pulses are delivered and which area of the brain is targeted, rTMS may increase or decrease activity within certain brain networks.
Researchers are studying TMS as both a treatment approach and a research tool. By observing how the brain responds to stimulation, scientists may gain a better understanding of the neurological processes involved in conditions such as VSS.
What Did the Study Investigate?
The case report involved an 18-year-old woman with VSS whose symptoms had not improved with lamotrigine or topiramate. She received ten daily sessions of low-frequency rTMS over a two-week period. The stimulation was delivered at a frequency of one pulse per second and targeted the superior parietal lobule on both sides of the brain.
The superior parietal lobule is involved in combining visual and sensory information and helping the brain understand where objects are located in relation to the body. Targeting this area is noteworthy because some earlier TMS research has focused more directly on the visual cortex at the back of the brain.
The intensity of the stimulation was personalized using the participant’s phosphene threshold. A phosphene is a sensation of seeing a flash or spot of light even when no light is entering the eye. Researchers can use this response to help measure how sensitive the visual areas of the brain are to stimulation.
What Were the Results?
Following treatment, the participant reported an improvement in her symptoms.
Functional magnetic resonance imaging, known as fMRI, and electroencephalography, known as EEG, also showed changes in brain activity following the rTMS sessions.
The researchers observed:
- Reduced communication between certain brain regions involved in visual processing
- Decreased gamma-band activity in areas associated with vision
- Changes consistent with reduced cortical hyperexcitability, a mechanism researchers believe may contribute to VSS
The findings suggest that low-frequency rTMS may have influenced activity across interconnected visual and sensory networks rather than affecting only one isolated area of the brain.
Looking Ahead
Visual Snow Syndrome can be difficult to manage, and current treatment approaches are limited. This case report adds to the growing body of research exploring whether non-invasive brain stimulation could influence the neurological activity associated with VSS. It also highlights the importance of determining which brain regions should be targeted, what stimulation frequency should be used, and how treatment could be personalized for each individual. Larger, controlled studies are needed to evaluate the safety, effectiveness, duration of improvement, and most appropriate treatment protocol.
Researchers in several countries are continuing to investigate TMS and other forms of non-invasive brain stimulation for Visual Snow Syndrome with support from the Visual Snow Initiative. These studies are helping scientists learn more about how visual, attentional, and sensory networks function in VSS.