June 2022 – It is clear that VSS is a disorder of the central nervous system. However, the underlying pathophysiological mechanisms remains elusive. More research is necessary to find out. Here, the researchers (led by dr. Fielding from Monash University) reveal no evidence of gross morphometry changes in the VSS brain, but widespread changes in the microstructure of the GM (Grey Matter), the most notable of these occurring in caudal regions including the occipital cortex. None of these changes are directly associated with the co-occurrence of migraine. While they were unable to determine the specific brain tissue that underlies microstructural changes, they do focus further investigations, contributing significantly to the understanding of VSS.
VSS is a distressing, life-affecting disorder with mostly relentless and persistent disturbing visual symptoms. The disorder usually begins around the age of 20 and is characterized by continuous perception of countless flickering dots (like a “broken television”).
Neuronally, VSS patients exhibit cerebral hypermetabolism, resulting in altered neuronal excitability, as well as increased gray matter volume in parts of the visual cortex.
For this pilot study, the researchers plan to recruit VS and VSS patients. In a double-blind, randomized, placebo-controlled longitudinal experiment, the researchers will use real-time functional magnetic resonance imaging (rtfMRI) neurofeedback to teach patients to downregulate activity in different regions of the visual cortex.
The researchers hypothesize that neurofeedback will enable patients to learn to lower their abnormal activity in the visual cortex. In addition, the researchers predict that a stronger downregulation of activity of the lingual gyrus will correlate with a more pronounced decrease in VS symptoms.
The patient will receive some compensation and a CD recording with the images from his/her rtfMRI. They will also look, if the patient wishes, to see if any abnormalities are noted on the rtfMRI.