Neural signaling in the retina: from genes to circuit function
One of the fundamental goals of neuroscience is to understand how information flow through a neural circuit leads to function and ultimately results in meaningful perception and behavior. Barring a few notable exceptions, this relationship between a neural input and behavior is yet to be established for most neural circuits in the brain. The retina provides an ideal model to explore this question for several reasons i) we know a great deal about different elements of the circuit – neuronal subtypes and their wiring, ii) we can control the input signals and directly measure neural responses from different elements of the retinal circuit and iii) it provides a unique opportunity to relate cellular and biophysical mechanisms to circuit-level function and behavior.
The visual information is parsed into > 20 parallel channels in the retina each of which is specialized to encode a certain feature of the outside visual scene. We study distinct neural circuits in the retina and ask how each neural circuit is custom-tailored to its function. A remarkable example of this specialization is in the fovea – a tiny region in primate retina that dominates our everyday visual experience, like our ability to read, write text and perceive color with the highest resolution. Our recent work (Sinha et al. Cell 2017) provided the first glimpse of how the fovea operates at a cellular, synaptic and circuit level and how different it is from rest of the retina. This has opened up a whole new avenue of research about retinal structure and function which gives us a unique opportunity to relate neural mechanisms to centuries worth of beautiful behavioral work on vision.