How neural circuits implement goal-based spatial navigation is an open question. In insects such as Drosophila, navigation and spatial-memory behaviors have been associated with a group of brain regions called the central complex. The central complex is a useful system to study the neural computations of navigation because heading direction signals (and likely other spatial variables) are topographically represented in genetically defined neuron types. This project aims to determine the sensorimotor and goal- related variables encoded in the fan-shaped body, one of the regions in the central complex. The experiments proposed here will use in vivo two-photon calcium imaging in tethered walking flies in a visual virtual-reality environment. Understanding the variables encoded by specific cell types in the fan-shaped body will provide insight into how internal representations of space are transformed into navigational goals and motor outputs.
Patients with psychiatric diseases such as bipolar disorder may have impairments in goal regulation; patients with cognitive neurological diseases such as Alzheimer's will often show difficulty with spatial navigation. The basic science of how brains are wired to compute and carry out these complex, integrative tasks remains unsolved. This study seeks to understand the precise circuits that implement goal-directed navigation in the fruit fly, which will provide important insights into the neural circuitry of cognitive behaviors in more complex animals, including humans.
