Ed Boyden, 33, makes tools for brain hackers. From his lab at MIT, he is building technology that will vastly expand the range of experiments that other scientists can pull off. His latest invention is a classic example: a robot that patch-clamps as well as a human scientist, with none of the fatigue or variability. It works all day. It does not need lunch breaks. It has transformed a technique that had only been mastered by an elite few into something that anyone can do, and hundreds of labs are queuing up to buy or make an auto-patcher of their own. Boyden published a description of the robot in May this year. He says, "After our paper came out, I got an email saying, 'I just spent a year learning how to do that. Thanks. There goes that'."
Boyden's ambition is audacious," says Craig Forest from the Georgia Institute of Technology, Boyden's partner on the auto-patcher project. Other colleagues agree. "It's regular to hear him say something like, 'I want to solve the brain.' Period. Nothing after that," says Anthony Zorzos, one of Boyden's graduate students. "But for a guy who says things like that, he's pretty down to earth." "Solving the brain" is as difficult as it sounds. A cubic millimetre of brain tissue can house 100,000 neurons, sending signals across a billion connections in mere thousandths of a second.
This cross-talk is what turns a lump of spongy tissue into the most sophisticated computer in existence. It is also impenetrable to modern methods. We can zoom out to scan broad regions encompassing millions of cells, or zoom in to dissect the traits of individual ones, but the intermediate world of circuits still eludes us.
Boyden likens our current technology to studying one pixel on a computer screen at a time. "Even if you buy a million screens, you won't understand how a computer works by looking at that one pixel," he says. "I'd rather have one computer and look at everything in it." The auto-patcher is one of the tools that Boyden is developing to observe neural circuits in detail, to better understand how the brain computes.
But voyeurism is not enough. Boyden is also designing tools to tweak, trigger and silence neural circuits, offering a degree of control that neuroscience has always lacked. For a long time, studying the brain meant finding correlations. Scientists measured how blood flow or electrical activity changed as we carried out mental tasks, and they noted how injuries and disease affected those abilities. But to establish causality, you have to stimulate neural circuits, as well as watch them. A movie, drug or electric shock will do the trick, but we need tools to stimulate specific sets of cells, not vast swathes of neurons.
The most famous of these is the one that made Boyden's name: optogenetics. By implanting neurons with light-sensitive proteins called opsins, harvested from algae, microbes and other creatures, scientists can stimulate or silence them with a simple optic fibre. Boyden pioneered optogenetics in 2005, with Karl Deisseroth from Stanford University. Now, it is used by thousands of scientists around the world.
The opsins can be loaded into neurons within just one part of the brain, or into neurons that secrete a certain type of signalling chemical. Flash the right set and you can steer an animal's movements, send it to sleep or make it aggressive. Silence the right ones and you could potentially calm the hyperactivity that accompanies epilepsy and Parkinson's disease.
"I'm wary of using the term revolutionary but I don't think it's an overstatement for optogenetics," says Robert Desimone, director of MIT's McGovern Institute for Brain Research and one of Boyden's collaborators. "It has affected virtually every lab working in neuroscience."
Via Dr. Stefan Gruenwald