Gordon Holmes’ systematic study of British soldiers with occipital gunshot wounds during the First World War produced the first detailed retinotopic map of human V1, predating the discovery of single-unit visual receptive fields by four decades. Holmes correlated visual-field defects with autopsy lesion locations to establish the calcarine cortex as the cortical termination of the central visual pathway and to demonstrate that the upper visual field is represented inferiorly (lingual gyrus) and the lower visual field superiorly (cuneus).

Modern retinotopic mapping with functional MRI has confirmed and extended this map, identifying at least a dozen distinct retinotopic visual areas across occipital, lateral, and ventral cortex (V1, V2, V3, V3A, V4, V5/MT, LO-1/2, hV4, VO-1/2, and others). The cuneus itself carries V1 and V2; the more lateral extrastriate areas extend into the fusiform and lateral occipital cortex.

Visual cortical activity persists in a degraded form in some “cortically blind” patients (blindsight), driven by surviving subcortical and extragenicular pathways through the superior colliculus and pulvinar. These patients can localise stimuli they report not seeing, suggesting that some visual functions are not strictly dependent on intact V1.