As an independent side project conducted concurrently to his PhD, he co-invented optogenetics. That technology uses light to control neurons, enabling scientists to figure out how neurons contribute to diseases such as Parkinson’s or schizophrenia. But despite this accomplishment, Boyden struggled to find an academic job that was a good fit. “Many people didn’t believe in trying to take a physical science approach to inventing tools to explore the brain.”
Then, in 2007, the MIT Media Lab accepted Boyden’s ambitious vision for probing our gray matter more accurately. “My long-term goal is to understand the brain with enough precision that we can simulate the computations that occur during decision-making or emotion,” he said. “Maybe we could even define what a thought is, computationally.”
To achieve that objective, Boyden says, one needs to do three things: watch the brain’s electrical activity and chemical signaling in action, map the wiring of its neural circuits, and perturb it with a previously unprecedented level of detail. Expansion microscopy, one of the more recent discoveries of his Synthetic Neurobiology Group at MIT, is a step toward that aim. The technology uses polymers to artificially inflate brain tissue samples, enabling scientists to map three-dimensional neural circuits with nanoscale precision.