Research
Not all neurons are alike. They can be grouped into types based on their unique morphological, molecular, connectional, and functional properties. These neuronal cell types are the fundamental circuit elements of the brain. They are combined in a myriad of ways in neural circuits to generate the powerful, flexible, and efficient neural computations that underlie cognition. Knowing the functions of each cell type would therefore reveal how computations are generated by neural circuits in the brain and how these computations can go wrong, leading to mental health disorders. We work to develop a framework to characterize cell type function. This framework combines neural connectivity data, functional and molecular profiling of the constituent cell types, and conceptual and theoretical models.
Our testbed is the navigation center in the Drosophila central brain. This brain region was recently imaged down to the level of individual synapses using electron microscopy. Automated techniques were then used to reconstruct the neurons within the volume and to label the synapses between them. We worked as part of a team to define the cell types within the navigation brain region and to characterize their connectivity. These cell types can be targeted with the powerful genetic tools that are uniquely available in the fruit fly.
We use these resources to define the cellular and circuit-level computations that allow an animal to remember and navigate to goal locations. The overall complexity of the network requires modeling and simulations, coupled with experiments, to describe the effects of feedback pathways. Complex, interconnected networks like the fly navigation center are vital to cognitive functions throughout the brain; they generate internal representations of the outside world and plan and execute action sequences. A detailed mechanistic description of such a network in the fly may therefore be invaluable to revealing algorithms of cognition.