DOI 10.1007/s00426-006-0063-5ORIGINAL ARTICLE

applied over the occipital pole can suppress visual per-ception. Since its Wrst description in 1989 by Amassian et al., this technique has widely been used to investigate visual processing at the cortical level. This article pre-sents a review of experiments masking visual stimuli by TMS. The psychophysical characterization of TMS masking, the dependence on stimulus onset asynchrony between visual stimulus and TMS pulse, and the topog-raphy of masking within the visual Weld are considered. The relation between visual masking and the generation of phosphenes is discussed as well as the underlying physiological mechanisms