What is kıyazma? Information about Kıyazma

In Greek, a word meaning cross. The visual nerve, visual pathways (x) as the cross is used for placement. Viewed Side of the animal (in birds, in fish), kiyazmada, sight paths cross is full, so you see life from the right eye, left side, right side pass from the left eye. Even the people visible in the way of seeing inside the cross is only the external part of the brain hemisphere goes to the same side. Thus each level divided into two kiyazma way to see the half of the visual nerve from each eye, combined with half coming from the other side goes to the brain. This cross at the same time as the two eye allows one to see.