Transcranial magnetic stimulation (TMS) on early visual cortex (i.e., areas V1/V2, MTþ/V5) can evoke visual percepts, known as phosphenes. Hence, TMS studies often rely on the induction of phosphenes as an early visual cortex localization method or as a brain excitability heuristic. Subsequently, researchers have depended on the induction of phosphenes for both applied and basic research. For example, studies have used phosphene induc- tion to understand brain excitability differences in migraine patients, to test new technologies, such as transcranial focused ultrasound, and to investigate the neural substrates of visual perception [3] and visual working memory