A real-time all-optical interface for dynamic perturbation of neural activity during behavior.

We developed a strategy for implementing a dream experiment in systems neuroscience, where circuit manipulation is guided by the real-time readout of neural activity in behaving mice. The system integrates a state-of-the-art calcium imaging analysis package that achieves rapid online activity readout from two-photon calcium imaging, a custom hologram generation program that targets two-photon optogenetic stimulation of specific neuronal ensembles, and software modules that automate essential steps in running complex all-optical experiments. Proof-of-principle experiments demonstrate that neurons can be automatically detected and recruited into a photostimulation ensemble, closed-loop photoinhibition can be implemented immediately after fast mapping of the functional properties of cortical neurons, and targeted activation can be guided by readout of ongoing activity patterns in behaviorally relevant neuronal ensembles during decision-making.