We invent molecular tools to study how the brain works. Brain circuits process information in the form of electrical and chemical signals to form memories and shape behaviors. However there is no natural contrast mechanism associated with these signals. In the lab, we use bioengineering and chemical approaches to develop molecular tools to visualize and study the brain. Our research combines electrophysiology, fluorescence imaging, protein engineering, and advanced genetic approaches to visualize the structure and function of the nervous system.