Mechanisms of local circuit dynamics in freely moving animals

Eran Stark, M.D. Ph.D.

NYU Neuroscience Institute

Much of what we know about how neurons interact and form ensemble activity patterns comes from recordings in cell cultures, brain slices, and anesthetized animals, yet dynamics in the intact brain of a behaving animal might differ. I will describe an approach to the study of local circuit dynamics in freely-moving animals, namely the combination of high-density extracellular recordings coupled with multi-site/multi-color electric/optogenetic stimulation, combined with in-vivo pharmacology and intracellular recordings. This approach, applied to the neocortex and hippocampus of behaving rodents, yielded surprising insight into mechanisms of information transfer, including spiking regime resonance, the generation of high-frequency oscillations, the temporal precision of spike transmission, and spike phase precession. Our approach opens the door to the study of local circuit dynamics underlying short term memory and to bi-directional interaction with the intact brain at the spatiotemporal resolution of single neurons and individual spikes.