Research data supporting "Mapping the visual brain areas susceptible to phosphene induction through brain stimulation."

Abstract

SUMMARY: This project investigated where in the visual cortex single pulse TMS can induce phosphenes. Participants were sitting in a dark room looking at a fixation on a screen infront of them. Stimulations were applied in 6x8cm (48 targets) grid over the visual cortex (10 stimulations per target). After each stimulation participants gave a response whether a percept had occured. STIMULATION: Stimulation at different locations was randomized. Stimulation location names refer to the row and column position in the target grid. Note that the count of rows and columns for this grid starts at 0 (e.g. grid_target_0_3 = target at row 1, column 4). At each location stimulation was applied with a individual stimulation intensity: Participants phosphene threshold + intensity adjusted for underlying distance between the coil and the grey matter surface. BEHAVIORAL RESULTS: z = No phosphene 1 = phosphene, slightly visible 2 = phosphene, visible 3 = phosphene, perfectly visible. fMRI: fMRI data was used to define retinotopic areas + LOC and MT. The .prt files describe the stimuli that were used for the localizer scans. MRI anatomical scans were used for neuronavigation. The coordinates of stimulation targets relative to anatomical (ACPC aligned) scans are in the neuronav.xlsx files. Note that neuroimaging data and neuronavigation data are in different coordinate space. CONTROL EXPERIMENT: In two sessions stimulations were applied at locations in the Main Exp grid with varying current directions. Current directions are identified by their angle relative to the current direction used in the main experiment (i.e. lateral to medial). Example: Current direction p270 describes a current direction that was rotated 270 degrees counterclockwise relative to lateral to medial. This results in a superior to inferior current direction.