Optogenetics: control of living cells by light

Finding how certain behavior such as food consumption, aggression, cognition and movement arise from the interactions of individual cells in the neural circuits is a major challenge in neuroscience. Genetically, pharmacologically or lesioning manipulations have been used to investigate the response of neural network during a behavioral task. However, these approaches lack temporal precision on the timescale of neural coding and signaling. Using optogenetics researchers can control and manipulate the activity of specific cell types and projections with the speed and precision uniquely applicable by light. Optogenetics has revolutionized the field of neuroscience, and has enabled researchers to investigate the causal roles of specific neural circuit components. Here, in this review we consider the current state of this technology and provide a brief introduction of different opsins used in optogenetics and applying optogenetics in vivo to investigate function of different neural networks.