Notes

If you plot the preferred colors of LGN neurons based on this coordinates system, you obtain a figure like the one above. We can notice that the points distribution is condensed in four main "columns" approximately 90 degrees from one another. The 0 and 180 deg populations are the red and green cells, while the 90 and 270 deg are the blue and yellow cells. This demonstrates that LGN cells come in the two families we have discussed except few outliers (which are very unusual). In addition, we can draw some analyses based on the cell position in the plot, e.g., a cell positioned at high-levels of elevation indicates a cell that strongly response to high-levels of light. On the other side, cells positioned at low-levels of elevation indicates cells that strongly respond to colors regardless of illumination.