In the first part of my talk, I will focus on mechanisms that regulate interactions between brain regions and describe how state-dependent frontal cortex dynamics can gate information flow from the sensory cortex during decision-making in mice.

In the second part, I will focus on information flow within the frontal cortex microcircuitry and present a new all-optical method for rapid mapping of local connectivity in vivo. Combining connectivity mapping with a novel paradigm of mouse innate behavior revealed functional connectivity motifs the frontal cortex and the existence of neurons that function as network hubs, which had an unexpectedly high number of connections and strong influence on neighboring neurons.

Finally, I will show that analyses of interactions between 1,000,000 neurons, recorded simultaneously across multiple cortical areas and different brain states, revealed a hitherto unknown organization of cortical population dynamics. Taken together, these results pave a road to study how neuronal interactions on different spatial scales give rise to behavior.