A Search Engine for the Brain Is in Sight

The human brain is smaller than you might expect: One of them, dripping with formaldehyde, fits in a single gloved hand of a lab supervisor here at the Jülich Research Center, in Germany.

Soon, this rubbery organ will be frozen solid, coated in glue, and then sliced into several thousand wispy slivers, each just 60 micrometers thick. A custom apparatus will scan those sections using 3D polarized light imaging (3D-PLI) to measure the spatial orientation of nerve fibers at the micrometer level. The scans will be gathered into a colorful 3D digital reconstruction depicting the direction of individual nerve fibers on larger scales—roughly 40 gigabytes of data for a single slice and up to a few petabytes for the entire brain. And this brain is just one of several to be scanned.

Neuroscientists hope that by combining and exploring data gathered with this and other new instruments they’ll be able to answer fundamental questions about the brain. The quest is one of the final frontiers—and one of the greatest challenges—in science.

Imagine being able to explore the brain the way you explore a website. You might search for the corpus callosum—the stalk that connects the brain’s two hemispheres—and then flip through individual nerve fibers in it. Next, you might view networks of cells as they light up during a verbal memory test, or scroll through protein receptors embedded in the tissue.