3D Road Map of the Human Brain: Unprecedented Details Revealed

There's been a lot of talk about mapping the human brain, tagging electrical signals in order to better understand how we think and function. Although that's certainly part of mapping the brain, it's not the whole story. There's also the physical component that researchers need to take into account. Now, scientists have made a landmark 3D digital reconstruction of a complete human brain, which gives researchers a road map of brain anatomy.

The new model is called BigBrain, which allows scientists to see brain anatomy in microscopic detail. In fact, it has a special resolution of 20 microns, which is smaller than the size of a human hair. It exceeds current reference brains present in the public domain and is freely available to the broader scientific community.

Considering that the brain controls and regulates all of the processes in our bodies, it's unusual that we don't know everything about it. The massively complex organ is actually the subject of the new brain mapping initiative, which aims to understand how the brain works by recording activity from an unprecedented amount of neurons at once. Efforts  are ramping up to better understand the control center of our bodies, and scientists have even recently mapped the emotions in the brain.

So how did researchers actually create this model brain? It wasn't easy. The scientists assembled images of over 7,400 individual histological sections, each with its own distortions, rips and tears, into one, 3D model.  In order to do this, they examined sections of a 65-year-old human female brain. This brain was embedded in paraffin wax and cut with a special large-scale tool called a microtome. Then, the 20-micrometer thick histological sections were mounted on slides, stained to detect cell structures and then digitized with a high-resolution flatbed scanner so that researchers could reconstruct the brain model.

After 1,000 hours of collecting data, the scientists were finally able to create the high-resolution brain model.  While this is an extraordinary feat and could help those studying the human brain immensely, there's still more work to be done.

"We plan to repeat this process in a sample of brains so that we can quantify cytoarchitectural variability," said Alan Evans, a professor at the Montreal Neurological Institute at McGill University, in a news release. The scientists also plan to integrate the dataset with high-resolution maps of white matter connectivity in post-mortem brains. This will allow the researchers to explore the relationships between cortical microanatomy and fiber connectivity.

This new model will allow scientists to gain further insight into the neurobiological basis of cognition, language, emotions and other processes. The new model could also be used to understand aging and neurodegenerative disorders, which could be crucial to uncovering new treatments and cures.

The findings are published in the journal Science.