In 2003, Microsoft cofounder Paul Allen spent $100 million to build the Allen Institute for Brain Science in Seattle. With laser-equipped microscopes and custom brain-slicers, the institute has mapped the brains of mice, monkeys, and humans, showing which genes are turned on—and where—to better understand vision, memory, autism, and other neural phenomena.

Last year Allen ponied up another $300 million to aim the institute at a narrower but more ambitious goal: a complete understanding of how the mouse brain interprets visual information. To succeed, they’ll have to go beyond static gene maps and learn how to watch a living brain in action.

The new method will track electrical activity in neurons—not just in one mouse but many. Called high-throughput electrophysiology, it’s the sort of big-science approach that the federal government is pushing with its Brain Research through Advancing Innovative Neurotechnologies initiative (yes, the acronym is indeed Brain), which the Allen Institute has been instrumental in planning. Allen talked with WIRED about his institute’s first decade and what he hopes it will do in the next.

Of all the things you could have invested in, why brain research?

Well, as a programmer you’re working with very simple structures compared to the brain. So I was always fascinated by how the brain works. I had a retreat with a bunch of scientists and basically polled them about what could be done to move the whole field ahead, and very quickly consensus formed around the idea of doing a complete genetic assay of the mouse brain. It’s an example of industrial-scale science where you bring together a team that’s focused on producing a database just like the Human Genome Project did.

How do you think your investment has paid off so far?

Oh, I think it’s had a real impact. If you talked to neuroscientists, they would say that everybody in the field who has a genetic component to their research uses our database. So that’s rewarding and heartening.