The inner workings of the human brain are still a fairly mysterious frontier despite all we've learned in recent decades, but a recently-completed initiative should provide a better map of what's inside our heads than anything we've seen thus far. According to Nature, scientists have successfully mapped the entirety of a human brain in 3D — a laborious process that involved cutting the brain of a 65-year-old woman into 7,400 slices, each of which is thinner than a human hair. The sections were then imaged by microscope over the course of 1,000 hours; the entire scanning process generated about 9 terabytes of data, which supercomputers in Canada and Germany spend years processing to build the 3D model.

That model, known as BigBrain, shows the brain at a resolution of 20 micrometres, which Nature says is 50 times higher than typical brain-scan models. Researchers are hoping this new high-resolution brain map will let them clarify, enhance, and distinguish between the many different parts of the brain with greater accuracy than ever before. Specifically, this new scan shows off extreme detail of the brain's neuron structure, including differences across the various layers and regions that are thought to relate to different brain functions. Of course, the researchers note that this is only one specific individual's brain, so it should really be thought of as an important part of the Human Brain Project (a 10-year European initiative to build a supercomputer simulation of the brain) rather than a definitive look inside our skulls.