A Simple Rule for Dendritic Spine and Axonal Bouton Formation Can Account for Cortical Reorganization after Focal Retinal Lesions
Figure 9
Schematic figure showing how structural plasticity in the model gives rise to functional network reorganization.
New horizontal connections form between neurons in the peri-LPZ and the border of the LPZ as well as between the border and the center of the LPZ. In the model, these new synapses are the source for functional reorganization comparable to cortical retinotopic remapping. A) Network before lesion. Colors indicate spatial locations in an input layer like the retina (not explicitly modelled) and the strongest neuronal response in the model network or the primary visual cortex. Vertical input from the eye is in black, horizontal recurrent connections are in gray. Linewidth indicates the number of synapses. B) Black bar indicates loss of input. Vertical input to this area is permanently removed (dashed arrow lines). Silent neurons in the LPZ early after the lesion are labeled black. C) Additional synapses are formed at the rim of the LPZ (bold black arrows) in the middle phase after the lesion. Due to additional horizontal synapses, neurons in the border become active in response to adjacent input representation (blue and red). D) Late after the lesion, additional synapses from the border to the center contribute to the activation of center neurons, which now also become sensitive to adjacent representations (blue and red).