In this image, the researchers used a newly developed polarized light microscope to plot the spatial orientation of neurons in a thin section of the mouse midbrain. Neurons that stretch horizontally displayed in green, while those oriented at a 45 degree angle are pinkish red and those at 225 degrees are purplish blue. These colors do not involve staining or labeling the cells with fluorescent markers: the colors are emitted strictly from light interacting with the physical orientation of each neuron.