Notes

The LGN presents 6 layers as it can be seen in the Macaque section shown to the left. Also, in the picture, the figures in the middle and to the right show that both LGN (left and right of the brain) receive inputs from both eyes, but these inputs are not mixed and remain segregated in the various layers.

Layers 1 and 2 are Magnocellular and are bigger cells with particular high contrast sensitivity but not color selective. While layers 3, 4, 5 and 6 are Parvocellular which are dimensionally smaller than Magnocellular. Although not particularly color sensitive either, they do show some sensitivity for red/green color opponency. Koniocellular layers are the smallest cells and show sensitivity for short-wave lengths, i.e., blue/yellow color opponency. The cells in the LGN share the center-surround structure of ganglion cells.

LGN plays a major role as a relay station to project the visual information towards other areas of the cortex. However, it doesn't seem to play any additional role in the processing of the information, compared to the retina.

Primary Visual Cortex (V1 = Areal 17 = Striate Cortex)