This PhD thesis and the scientific papers included in it were intended to provide new knowledge regarding the sensory substitution of vision and the crossmodal recruitment of the visual cortex in human beings. Sensory substitution refers to the use of one sensory modality (e.g., hearing) to supply environmental information normally gathered by another sense (e.g., vision) while still preserving some of the key functions of the original sense. For example, the use of auditory signals might give information about visual scenes. The development of sensory substitution devices has profoundly changed the classical definition of sensory modalities, bringing new insights into human perception. The present thesis aimed to study possible behavioral and cerebral adjustments in sensory function when using sensory substitution to provide visual percepts in sighted people studied blindfolded. An additional concern was to investigate the effects of early visual deprivation on perception and semantic processing of visual objects, using schematic drawings of houses and faces as the stimuli. In the introduction section (first chapter) we presented a review about the functional organization of the human visual cortex and how the study of sensory substitution contributed to qualify this classical view by highlighting the multisensory recruitment of visual brain areas. The second chapter surrounds the experimental works included in this PhD thesis that combined behavioral methods from psychophysical tests and cerebral imaging techniques to document further the multisensory organization of the visual cortex. Therefore, here we were focused on the visual cortex recruitment when audition substituted vision. In two neuroimaging studies using fMRI (study 1 and 2) we aimed to verify whether visual-like perception during the use of a visual-to-auditory sensory substitution device modulated the brain activity within the dorsal visual stream (in study 1, which concerned location and orientation processing) and in specific brain areas of the ventral visual pathway (in study 2, focused on face recognition). The purpose of study 3 was to investigate the neural correlates of face perception through sensory substitution of vision in early blind subjects. Specifically, using fMRI, we aimed to know whether the fusiform face area of early blind subjects was engaged during perceptual processing of schematic faces, which should further indicate the multisensory character of the occipital cortex in the absence of visual input. The third chapter concerns the general discussion and conclusions of the different results found in the experimental works included in this PhD thesis. (BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2013