Concepts of all-optical physiology

Abstract

All-optical physiology represents a methodological approach using light for both readout from and manipulation of individual neurons. This approach paves the way for a true, causal analysis of neuronal activity with single-cell and single action potential resolution and is therefore highly desirable for the investigation of neural networks. The following chapter addresses the general concepts of all-optical interrogations by shedding light on all critical steps needed for these experiments: Calcium-sensitive probes for readout, next-generation two-photon-excitable optogenetic actuators for manipulation and advanced optics for efficient stimulation of and real-time readout from individual neurons. The chapter also provides a step-by-step protocol on an all-optical strategy using an optical parametric oscillator (OPO) for photostimulation of opsin-expressing cells alongside simultaneous two-photon calcium imaging.