Figure 1. Gray matter (GM) volume increase in the left visual cortex in visual snow syndrome.

Left primary visual cortex increases in GM volume in patients with VSS with respect to controls (x = −2, y = −98, z = 3; k = 594; p = 0.007 uncorrected, p = 0.06 family-wise error). Results are from whole-brain analysis; GM volume differences between groups are outlined over T1 images. Bar represents T values.