New neural pathway found in eyes that aids in vision

A less-well-known type of retina cell plays a more critical role in vision than previously understood. Working with mice, the scientists found that the ipRGCs -- an atypical type of photoreceptor in the retina -- help detect contrast between light and dark, a crucial element in the formation of visual images. The key to the discovery is the fact that the cells express melanopsin, a type of photopigment that undergoes a chemical change when it absorbs light.