This thin section of brain has been treated with a pink neuropathological stain to show fine anatomic detail.

Any time someone concatenates the words "Paul Allen," "brain," and "science" in one sentence, two assumptions can safely be made: What's being described will be expensive' what's being described will be newsworthy.

And so it comes as little surprise that the Seattle-based Allen Institute for Brain Science announced this week a world first: a highly detailed guide to both the anatomy and the genes of the human brain that includes 1,000 anatomical landmarks backed by 100 million data points measuring the strength of gene activity at each landmark. The cost of its creation $55 million.

"Until now, a definitive map of the human brain at this level of detail simply hasn't existed," the nonprofit's chief executive, Allan Jones says in a news release. "Understanding how our genes are used in our brains will help scientists and the medical community better understand and discover new treatments for the full spectrum of brain diseases and disorders, from mental illness and drug addiction to Alzheimer's and Parkinson's diseases, multiple sclerosis, autism and more."

Funded in part by Microsoft co-founder Paul Allen, the Allen Human Brain Atlas project spanned four years as a team of researchers sliced thin layers from two normal adult male brains donated to science. They then assembled the imaging of those slices into an interactive atlas that is already being used in its preliminary version--with free public access online to the entire archive--by more than 4,000 scientists.

As these things go, the project is by no means finished. What began as a mapping of the mouse brain in 2006 has moved on to the human brain, but the current online archives include only those two brains, which have been found to be 94 percent similar.

Next step: add eight more brains to the archives by year's end, at least one of which researchers say will be female.

The institute describes the mapping as "a previously unthinkable feat" that behaves much like a "high-powered, multifunctional GPS navigation system." And with at least 82 percent of all human genes expressed in the brain, the archives should provide "an essential genetic blueprint to understand brain functionality better and propel research in neurologic disease and other brain disorders."

With the mouse brain atlas spawning hundreds of research projects, only time will tell what this burgeoning brain imaging vault will reveal to us about ourselves.