FACED 2.0 enables large-scale voltage and calcium imaging in vivo

Monitoring neuronal activity at large scale and high spatiotemporal resolution is crucial for understanding information processing within the brain. We optimized a kilohertz-frame-rate two-photon fluorescence microscope with all-optical megahertz line-scan rate to achieve ultrafast imaging across large areas and volumes at subcellular resolution. Applying this technique to voltage and calcium imaging in vivo , we demonstrated simultaneous recording of voltage activity over 200 neurons and calcium activity over 14,000 neurons.