Retinotopy

[5] In the late 19th-century, independent animal studies including some on dogs by the physiologist Hermann Munk and some on monkeys by the neurologist David Ferrier elucidated that lesions to the occipital and parietal lobes induced blindness.Around the turn of the century, Swedish neurologist and pathologist Salomon Henschen had a prolific body of work on the mind that included much research on neuropathology.Maps were described and analyzed by the Japanese ophthalmologist Tatsuji Inouye when studying soldiers' injuries incurred in the Russo-Japanese War, although his work on the subject—published in 1909 through a German monograph—was largely ignored and abandoned to obscurity.Independently of Inouye a few years later, the British neurologist Gordon Holmes made similar advances studying the injuries suffered by soldiers in World War I.The "chemoaffinity hypothesis" was established by Sperry et al in 1963 in which it is thought that molecular gradients in both presynaptic and postsynaptic partners within the optic tectum organize developing axons into a coarse retinotopic map.Dark reared animals (no external visual cues) develop a normal retinal map in the tectum with no marked changes in receptive field size or laminar organization.This patterned firing will result in stronger connectivity within the retinotopic organization through NMDAR synapse stabilization mechanisms in the post synaptic cells.[20] This plasticity is not specific to retinal ganglion axons, rather it's been shown that dendritic arbors of tectal neurons and filopodial processes of radial glial cells are also highly dynamic.