If I didn’t know Sebastian Seung was a neuroscientist, I would have pegged him as a computer game designer. His onyx-black hair seems frozen in a windstorm. He wears black sneakers, jeans, and a frayed bomber jacket over an untucked shirt covered in fluorescent blobs. If someone had blindfolded me on Vassar Street in Cambridge, Massachusetts, led me into Building 46 on the campus of MIT, past the sign that says Department of Brain and Cognitive Science, taken me up in the elevator to the fifth floor and whisked off the blindfold in Seung’s lab, I still wouldn’t have guessed he had anything to do with brains. There are no specimens floating in jars on the shelves. There are no electrodes plugged into the heads of sea slugs. Instead, I see a dozen young men gazing at monitors, some pushing their computer mice, others drawing tethered pens across digital tablets to manipulate 3-D images, each packed with more megabytes than a feature film on a Blu-ray Disc.
And there is Seung himself, gazing over the shoulder of postdoc Daniel Berger, whose monitor looks like a science fiction forest, with branches and trunks colored turquoise and cherry, floating unrooted in space. I almost find myself wondering when Seung’s next game will hit the stores.
But appearances to the contrary, Seung is an expert on the web of neurons that make up the brain. And the images he’s creating are part of an ambitious attempt to understand how the connections between those brain cells give rise to the mind. “How do you put together dumb cells and get something smart?” he asks.
Neuroscientists know that the brain contains some 100 billion neurons and that the neurons are joined together via an estimated quadrillion connections. It’s through those links that the brain does the remarkable work of learning and storing memory. Yet scientists have never mapped that whole web of neural contact, known as the connectome. It would be as if doctors knew about each of our bones in isolation but had never seen an entire skeleton. The sheer complexity of the connectome has put such a map out of reach until now…
Image: Each branch of each neuron is studded with hundreds of little spines. R. Schalek, B. Kasthuri, K. Hayworth, J. Tapia, J. Lichtman/Harvard and D. Berger, S. Seung/MIT