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Evidence from human and primate studies suggests that fast visual processing may utilize signals projecting from primary visual cortex (V1) through the dorsal stream, to area V5/MT+ or beyond and subsequently back into V1. This coincides with the arrival of parvocellular signals en route to the ventral pathway and infero-temporal cortex. Such evidence suggests that the dorsal stream region V5/MT+ is activated rapidly through the traditional hierarchical pathway and also via a less-well-established direct signal to V5/MT+ bypassing V1. To test this, 16 healthy humans underwent transcranial magnetic stimulation (TMS) of V1/V2 and V5/MT+ while performing a motion-direction detection task. A three-alternate forced-choice design (left/right motion, stationary) allowed analysis of the quality of errors made, in addition to the more usual performance measures. Transient disruption of V1/V2 and V5/MT+ significantly …