Divergence-Convergence ratios govern functional circuitry in the Early Visual Pathway

Abstract

In the second place, since retinotopy is the most present and relevant functional constraint across mammalian species. A mathematical model of the development of correctly oriented topographic maps in visual cortex is presented that takes into account the synchronization between the two retinas mediated by retino-retinal (R-R) connections, to explain the role of molecular and activity dependent mechanisms in the establishment of retinotopic maps across phylogeny. Demonstrating that the presence or absence of R-R connections across different species is completely related to their different DCr values through phylogeny. In third place, we present a set of experimental results where V1 of a strain of mutant mice (Brn3b-Zic2) that have a larger proportion of ipsilateral fibres, was characterized using optical imaging of intrinsic signals. This manipulation alters the input that reaches V1 and, therefore, increases the DCr of the ipsilateral fibres through the EVP. As a result, Brn3b-Zic2 mice develop Ocular Dominance (OD) columns that resemble those presented in Ocular Dominance maps (ODM) of carnivores and primates, which emphasizes the role that the DCr plays in the development of V1 functional structure.