Photosensitive ganglion cells: A diminutive, yet essential population.

Photosensitive ganglion cells: A diminutive, yet essential population. Arch Soc Esp Oftalmol. 2020 Oct 30;: Authors: Vidal-Villegas B, Gallego-Ortega A, Miralles de Imperial-Ollero JA, Martínez de la Casa JM, García Feijoo J, Vidal-Sanz M Abstract Our visual system has evolved to provide us with an image of the scene that surrounds us, informing us of its texture, colour, movement, and depth with an enormous spatial and temporal resolution, and for this purpose, the image formation (IF) dedicates the vast majority of our retinal ganglion cell (RGC) population and much of our cerebral cortex. On the other hand, a minuscule proportion of RGCs, in addition to receiving information from classic cone and rod photoreceptors, express melanopsin and are intrinsically photosensitive (ipRGC). These ipRGC are dedicated to non-image-forming (NIF) visual functions, of which we are unaware, but which are essential for aspects related to our daily physiology, such as the timing of our circadian rhythms and our pupillary light reflex, among many others. Before the discovery of ipRGCs, it was thought that the IF and NIF functions were distinct compartments regulated by different RGCs, but this concept has evolved in recent years with the discovery of new types of ipRGCs that innervate subcortical IF regions, and therefore have IF visual functions. Six different types of ipRGCs are currently known. These are termed M1-M6, and differ in their morphol...
Source: Archivos de la Sociedad Espanola de Oftalmologia - Category: Opthalmology Tags: Arch Soc Esp Oftalmol Source Type: research