Neuroengineer and speaker at the TED2011 conference, Ed Boyden runs the synthetic neurobiology group which develops software, electrical and optical tools to allow people to analyse brain dynamics: "Unlike a computer, the brain is made of thousands of different types of cell, and we don't know how they work. We need to be able to turn the cells on and off to see how they cooperate to implement brain computations, and how they go awry in brain disorders. What we're doing is making genetically encoded neurons that we can turn on and off with light. By shining light on these cells we can activate them and see what they do."