Our brains are among the most interesting specimens for scientists to study, but they’re also among the most difficult. A human brain is a nightmare of complexity, made up of an estimated 86 billion neurons, which are wired together in trillions of connections. Making matters worse, scientists can’t pop open people’s skulls and tinker with their brains just to see what happens next.
Over the past few years, Kaplan and his colleagues at the Tufts University School of Engineering have perfected a recipe for growing millions of neurons inside a scaffolding of pure silk. The neurons, drawn from mice, join together and send signals to each other, like real brains do. And they can survive in these brain-like webs for months.
For now, Kaplan and his colleagues are studying mini-brains to see how they respond to different stimuli — from drugs to concussion-like injuries. And as they get more acquainted with these mini-brains, they’re trying to join them together like Lego bricks to make bigger networks. We can only dream (or dread) what those maxi-brains might someday do.