Correlational model for joint development of refined retinotopic map and ocular dominance columns

We describe a modification to a standard correlation model for the development of the geniculocortical projection that relays visual input to the visual cortex. The modification is to include threshold-activation of cortical cells as opposed to linear activation and it is shown that this can account for topographic map refinement (TMR). This contrasts with other models that require cortical cells to compete for activation or for neurotrophic support. Simulations are conducted for the joint development of ocular dominance columns and TMR in normal animals and parameter variations are used to both confirm robustness and to simulate some experimental conditions.