Neurons in the retina



Introductory neuroscience classes teach that there are five classes of neurons in the retina: photoreceptor, horizontal, bipolar, amacrine, and ganglion cells. Contemporary researchers are finding that the retina is far richer than this textbook account. The five classes of retinal neurons are divided into well over 50 types, each with a distinct function in vision.

In particular, ganglion cells come in at least 15 or 20 types, each of which sends a different kind of visual information to the brain. This is a far cry from the simplistic textbook portrayal of ganglion cells as all performing center-surround filtering. Each ganglion cell type is thought to be part of a distinct neural circuit in the retina, meaning that is synaptically coupled to a unique set of bipolar and amacrine cell types. However, these neural circuits are almost completely unknown.

EyeWire will identify and reconstruct specific types of ganglion cells identified either by their shapes or their visual response properties. Then they will search for the amacrine and bipolar cells that are presynaptic to the ganglion cells. The resulting findings will be used to test models of ganglion cell computation.

== Anatomy of retina ==

Ganglion cell layer
Ganglion Cell soma, Ganglion Cell axon bundle, displaced Amacrine Cell soma

Inner plexiform layer
Dendrites of Ganglion Cell Dendrites of Amacrine Cell Axons of Bipolar Cell

Inner nuclear layer
Amacrine Cell soma Bipolar Cell soma Horizontal Cell soma

Outer plexiform layer
Bipolar Cell dendrite, Horizontal Cell dendrite, Photoreceptor inner segment

Outer nuclear layer
Rod and Cone granule