Midget cells

A midget cell is one type of retinal ganglion cell. Midget cells originate in the ganglion cell layer of the retina, and project to the parvocellular layers of the lateral geniculate nucleus (LGN). The axons of midget cells travel through the optic nerve and optic tract, ultimately synapsing with parvocellular cells in the LGN. These cells are known as midget retinal ganglion cells due to the small sizes of their dendritic trees and cell bodies. About 80% of RGCs are midget cells. They receive inputs from relatively few rods and cones. In many cases, they are connected to midget bipolar cells, which are linked to one cone each. They have slow conduction velocity, and respond to changes in color but respond only weakly to changes in contrast unless the change is great. They have simple center-surround receptive fields, where the center may be either ON or OFF while the surround is the opposite.