Wiersma Lecture

A longstanding challenge in neuroscience is to understand how populations of individual neurons contribute to animal behavior and brain disease. Addressing this challenge has been difficult partly due to lack of appropriate brain imaging technology for visualizing cellular properties in awake behaving animals. I will discuss several new optical technologies of this kind. The miniature integrated fluorescence microscope allows one to monitor the dynamics of up to ~1000 individual genetically identified neurons in behaving mice over weeks. I will describe ongoing studies using this technology to understand the neural codes underlying episodic, emotional and reward related memories. Toward elucidating the interactions between brain areas during active behavior, multi-axis optical imaging can record the dynamics of two or more neural ensembles residing in different brain regions. For high-speed imaging studies, genetically encoded voltage indicators are improving rapidly in their capacities to allow high fidelity detection of neural spikes and accurate estimation of spike timing. Lastly, I will introduce robotic technology to facilitate brain imaging and experimentation in awake behaving fruit flies.