Large-scale remapping of visual cortex is absent in adult humans with macular degeneration

Previous work suggests that occipital pole areas corresponding to the central retina can be driven by retinal activity elsewhere when the central retina is lesioned. This fMRI study in individuals with macular degeneration with retinal lesions finds no evidence for such remapping of activity, suggesting that plasticity in adult visual cortex is limited. The occipital lobe contains retinotopic representations of the visual field. The representation of the central retina in early visual areas (V1–3) is found at the occipital pole. When the central retina is lesioned in both eyes by macular degeneration, this region of visual cortex at the occipital pole is accordingly deprived of input. However, even when such lesions occur in adulthood, some visually driven activity in and around the occipital pole can be observed. It has been suggested that this activity is a result of remapping of this area so that it now responds to inputs from intact, peripheral retina. We evaluated whether or not remapping of visual cortex underlies this activity. Our functional magnetic resonance imaging results provide no evidence of remapping, questioning the contemporary view that early visual areas of the adult human brain have the capacity to reorganize extensively.