Functional reorganization of the visual cortex in blindness: a connectivity perspective

Abstract

Visual deprivation provides a critical model for understanding how sensory experience and developmental constraints shape cortical organization. In blindness, the occipital cortex is recruited for tactile and auditory perception as well as language, memory, mathematical processing, and executive control. The core question is how visual cortex becomes functionally embedded in non-visual and cognitive systems, and how this embedding gives rise to particular forms of occipital recruitment. Connectivity is central to this question because cortical functions are shaped, in part, by the information a region receives, the pathways through which it exchanges signals, and its coordination with distributed systems. Connectivity therefore links developmental constraints and sensory experience to functional emergence: it specifies which signals can influence occipital regions, which networks can incorporate them, and which functional roles they may come to support. Resting-state studies show that some retinotopy-consistent features of local occipital organization persist without visual experience. At the same time, reduced homotopic and interhemispheric connectivity suggests altered coordination within the visual system. Long-range functional connectivity reveals coexisting patterns: ventral occipitotemporal regions can retain broadly sighted-like connectivity profiles, while occipital cortex also shows enhanced coupling with frontoparietal, language-related, and other higher-order networks. This large-scale network embedding provides a mechanistic account of how occipital regions can participate in higher-order cognition. Structural connectivity offers a complementary but still limited account. Most studies report alterations in visual afferent pathways, occipital white matter, posterior association fibers, and posterior callosal pathways, and these findings have often been interpreted within a deficit-oriented framework. However, structural findings alone do not yet explain how anatomical connectivity supports functional recruitment, how structural profiles relate to functional connectivity, or how structure–function coupling develops with sensory history and individual experience. Whole-brain connectome studies further point to altered network efficiency, path length, and structure–function alignment, but the mechanisms linking these features to occipital function remain unresolved. Together, current evidence suggests that connectivity should be treated as a mechanism of occipital plasticity. Future work should clarify how preserved architectural scaffolds, anatomical constraints, and experience-dependent functional coupling jointly shape the emergence of non-visual and cognitive functions in the blind occipital cortex.