Visual functions are entangled with cortical areas responsible for transcoding the images we see each second. Moreover, cortical integrity is important for visual functions to operate properly. Stroke, optic neuropathy, or glaucoma would result in vision loss or Visual field defect (VFD). In addition, homonymous hemianopia is a commonly observed defect. Recently, one of the commonly used procedures to relieve VFD is non-invasive brain stimulation (NIBS): a superficial stimulator coil that generates an electric current directed to the area of interest.

Current evidence suggests that rTACS exhibits a promising approach in homonymous hemianopia patients, where it significantly increased HRP DA. Despite the results' failure to attain statistical significance in some outcomes, it underscores the necessity for larger RCTs with longer follow-up periods.