Mapping the human brain to better understand its functions and diseases
Imagine developing a 3D atlas of the human brain, the most complex organ in the body, and ultimately simulating it to help improve research on and treatment of conditions like epilepsy and cancer. This is what the EU-funded project HBP SGA3 has set out to do, and scientists have recently presented the most comprehensive digital map of the brain’s cellular architecture. They have also made it accessible via the EBRAINS research infrastructure of the European Human Brain Project (HBP). Their findings were published in the journal ‘Science’. “We introduce Julich-Brain, a three-dimensional atlas containing cytoarchitectonic maps of cortical areas and subcortical nuclei. The atlas is probabilistic, which enables it to account for variations between individual brains.” As the researchers note in the same journal article, such an atlas should “integrate recent knowledge about brain parcellation, consider variations between individual brains, rely on reproducible workflows, and provide web-based links to other resources and databases.” The researchers have “developed a computational framework and refined the current boundaries of the human brain based on cytoarchitectural patterns.” A press release on the project website explains how the Julich-Brain atlas demonstrates “the variability of the brain’s structure with microscopic resolution. The atlas features close to 250 structurally distinct areas, each one based on the analysis of 10 brains. More than 24 000 extremely thin brain sections were digitized, assembled in 3D and mapped by experts.” According to study author Prof. Dr med Katrin Amunts, Director of the Institute of Neuroscience and Medicine at HBP SGA3 project partner Forschungszentrum Jülich, “the digital brain atlas will help to interpret the results of neuroimaging studies, for example of patients, more accurately.” In the same press release she comments that the atlas “is becoming the basis for a kind of ‘Google Earth’ of the brain - because the cellular level is the best interface for linking data about very different facets of the brain.”
No two brains the same
The study shows that the areas of the brain vary between different individuals, “for example in terms of size and location. The Julich-Brain therefore displays the position and shape of individual regions as ‘probability maps’.” As noted in the press release, there were “particularly large differences in the Broca region, which is involved in language. In contrast, the primary visual area appeared much more uniform.” Project partners emphasise that their atlas “is the starting point for bringing structure and function together. The atlas is already helping to link data on gene expression, connectivity and functional activity, for example, to better understand brain functions and the mechanisms of diseases.” Thanks to the EBRAINS platform, the maps developed by the researchers could be used “for simulations or to apply artificial intelligence to explore the division of labor between brain areas.” HBP SGA3 (Human Brain Project Specific Grant Agreement 3) will run until March 2023. It is the final phase of the HBP, a Future and Emerging Technologies Flagship project that is among the biggest projects ever funded by the EU. “The plan is that the end of the Flagship will see the start of a new, enduring European scientific research infrastructure, EBRAINS, hopefully on the European Strategy Forum on Research Infrastructures (ESFRI) roadmap,” as stated in the project factsheet. For more information, please see: HBP SGA3 project website
Keywords
HBP SGA3, Human Brain Project, EBRAINS, brain, Julich-Brain
