Visual deprivation leads to massive reorganization in both the structure and function of the occipital cortex, raising crucial challenges for sight-restoration. We tracked the behavioral, structural and neurofunctional changes occurring in an early and severely visually impaired patient before, 1.5 and 7 months after sight restoration using magnetic resonance imaging. Robust pre-surgical auditory responses were found in occipital cortex despite residual preoperative vision. In primary visual cortex, crossmodal auditory responses overlapped with visual responses and remained elevated even 7 months post-surgery. However, these crossmodal responses decreased in extrastriate occipital regions after surgery, together with improved behavioral vision and with increases in both grey matter density and neural activation in low-level visual regions. Selective responses in high-level visual regions involved in motion and face processing were observable even pre-surgery and did not evolve after surgery. Taken together, these findings demonstrate that structural and functional reorganization of occipital regions are present in an individual with a longstanding history of severe visual impairment, and that such reorganizations can be partially reversed by visual restoration in adulthood.
- crossmodal plasticity
- ventral-dorsal pathways
- Copyright © 2014, Journal of Neurophysiology