Four and a half years ago, the Allen Institute for Brain Science in Seattle launched a little project called the Allen Brain Atlas. This week, it’s complete, and thanks to the hard work of an international team led by Michael Hawrylycz, we now have a high-res, searchable 3D map of the human brain. Even better? It’s free to anyone with internet access.

A map of the mouse’s brain has been available for some time, but human brains are larger, more complex, and, um… a little harder to come by. Incredibly, the Allen Brain Atlas was created with the thorough probing and study of just two and a half brains. That’s right — the guys building the world a blueprint of our own minds couldn’t even score the other half of a third brain to work with. Fortunately, the team were quite thorough, breaking down their admittedly limited tissue into 900 small subdivisions and probing 60,000 gene expressions. The result is the most complete, most accurate rendering of a human brain we have ever had. Here’s hoping the next round can get a little more material to work with.

Check out the Allen Brain Atlas, and consider donating your real, actual brain to teams like this one when you’re released from this mortal coil. Brains aren’t cheap, Geeks — this project cost $55 million (that’s $11 million per hemisphere) — and you probably won’t be doing much with yours then anyway. :P

[via New Scientist] Image: Allen Institute for Brain Science