James Butler

In 2005, Boyden et al. used the protein channelrhodopsin-2 to generate the first ever light-induced action potential, involving a single component device. Since then, an explosion of so-called ‘optogenetic’ research has occurred. This abundance of new discoveries is reviewed here in depth. First, methods of targeting optogenetic techniques are discussed in brief. Next, both optogenetic sensors, used for observing neural circuits, and single-component optogenetic effectors, used for manipulating neural circuits, are assessed. The discoveries that these new technologies have led to is presented, current limitations of the respective technologies are examined and directions of future research discussed.