Colour centre This is more important for perceiving the colour of objects and pictures. The double-opponent cells are receptive to opposite inputs from different cone cells in the retina. This is ideal for identifying contrasting colours, such as red and green. [1] Double-opponent cells are particularly important in computing local cone ratios from visual information from their receptive fields. Single opponent colour-sensitive neurons can be divided into two categories depending on the signals they receive from the cone cells: L-M neurons and S/(L+M) neurons. The three types of cone cells, small (S), medium (M), and long (L), detect different wavelengths across the
Intrinsically photosensitive retinal ganglion cells these cells may receive excitatory and inhibitory influences from rods and cones by way of synaptic connections in the retina. The axons from these ganglia innervate regions of the brain related to object recognition, including the superior colliculus and dorsal lateral geniculate nucleus. These photoreceptor cells project both throughout the retina and into the brain. They contain the photopigment melanopsin in varying quantities along the cell membrane, including on the axons up to the optic disc, the soma, and dendrites of the cell. ipRGCs contain membrane receptors for the neurotransmitters glutamate, glycine, and GABA. Photosensitive ganglion cells respond to light