smallfieldbistratified

Smallfieldbistratified is a type of retinal ganglion cell found in the primate retina. It is characterized by a small receptive field and a dendritic arbor that stratifies in two distinct sublaminae of the inner plexiform layer, making it bistratified.

Anatomy and connections: The cell has a compact dendritic field and projects to central visual pathways, including the lateral geniculate nucleus. Its dendrites extend into both the ON and OFF sublayers of the inner plexiform layer, allowing integration of signals across ON and OFF pathways. The cell receives synaptic input from bipolar and amacrine cells, with a notable input from short-wavelength (S) cones via blue-cone pathways.

Physiology and color vision: Smallfieldbistratified cells are color-opponent neurons that contribute to blue-yellow color discrimination. They tend to respond to blue (S-cone driven) signals in one IPL layer and to longer-wavelength (M/L-cone) signals in the opposing layer, creating a blue-yellow opponency. Their small receptive field size supports higher acuity color processing in certain retinal regions.

Significance and status: They are among several retinal ganglion cell types that diversify color and luminance processing beyond the well-known midget and parasol pathways. They are relatively less numerous than midget or parasol cells. The cell type helps explain early color processing in the retina and contributes to the blue-yellow color-opponent channel that feeds into higher visual areas.