Many of the computations performed by the nervous system can be interpreted as answers to particular challenges posed by the live histories of an animal. For example, the need to be alert to approaching prey or ability to process optic flow information to guide movement through the environment. In the visual system, the extraction of salient features from the environment begins in the retina, and as information progresses to higher brain centers neurons become tuned to increasingly complex visual features. However, the diversity of the retina’s outputs has yet to be incorporated into our understanding of higher visual function. The major focus of the lab is to put the function of individual visual channels originating in the retina into context by linking them with their destinations in the brain and determining their role in visually guided behavior.
The retina as a platform from which to study the function of central brain regions
This set of projects will combine trans‐synaptic viral tracing techniques with calcium imaging and optogenetic approaches to determine how the different channels of the retina distribute visual information to higher brain centers. To limit ourselves to direct lines of communication it is planned to restrict the search for disynaptic connections, involving a single relay, between the retina and the central brain target of interest. We are currently focusing on pathways passing through the superior colliculus. This set of experiments will allow us to determine which retinal channels are assigned dedicated computational tasks, if some channels are recombined in the relay stations of the brain (LGN and superior colliculus), and solidify our understanding about the dictionary of information that is sent to different brain regions.
Whole brain imaging and the cell type specific projections
In collaboration with the lab of Alan Urban we are using whole brain functional imaging to map the effective projections of single cell types in the retina and superior colliculus.
The retinal as a model system to study local neural circuitry
Each type of retinal output neuron has an afferent circuit in which a few other cell types take part. These circuits are repeated across the retina in a series of mosaics. By examining the structure of genetically identified neural circuits one can address fundamental questions about the functional architecture of the retina. To study these microcircuits independently we combine trans-synaptic circuit tracing, two-photon targeted patch-clamp recording and calcium imaging techniques to label and record the activity from all members of an individual microcircuit.