Brain Tracing

Our understanding of the early visual system is at a crossroads; although we have a comprehensive list of brain areas that receive retinal input, we know very little about which retinal ganglion cell types project to each region. The canonical pathway in mammals from retina to dorsal lateral geniculate nucleus (dLGN) to cortex is required for visual perception. This pathway has been a research focus for decades, yet it represents only a small fraction of the visual input to the brain, and conscious perception is one one of the many behaviors influenced by retinal input. A goal of my lab is to establish comprehensive connectivity maps from retina to brain at the level of identified cell types.
[Left] A mouse retina with specific cells (red) back-labeled from their brain projections. A single cell is filled in green.
[Bottom Left] Schematic of a subset of the known projection patterns from the retina to the brain.
[Bottom Right] A fluorescent virus (red) is injected in a specific location in the brain and transported back to the retina.