According to the
researchers, the atlas called "BigBrain," was prepared by mounting thin sliced sections of the whole-brain on slides. The stained sections were then scanned and reconstituted by supercomputers into a 3D model of an entire brain.
Nature reports that imaging the sections using microscopes took about 1,000 hours and generated an estimated 1 trillion bytes of data.
It took several years for supercomputers in Germany and Canada to reconstruct images of the slide-mounted thin sections into a 3D volume image of the brain, taking into account tears and wrinkles in individual slices of thin and thus fragile tissue.
The BigBrain atlas shows the analytic details of organization of cerebral neurons at an unprecedented resolution of 20 micrometers, about 50 times higher than the resolution of previous atlases of the brain constructed from whole brain scans, according to
Nature.
The unprecedented precision achieved on a finer scale than ever before, could help to extend and maybe even redefine scientific knowledge of the anatomy of brain regions as established through previous projects.
According to the study authors in a paper titled
"BigBraiin: An Ultrahigh-Resolution 3D Human brain model," published in the journal
Science, the atlas shows the distribution of neurons in different layers of the cerebral cortex, including details of variations across different regions of the brain. It addresses the limitations of previous macroscopic scale atlases of the brain which fail to provide sufficient information on the microscopic scale. According to the
authors, BigBrain will enable "redefining the traditional neuroanatomy maps such as those of Brodmann and von Economo."
The neuroscientists said they will make "BigBrain" freely available online.
David Van Essen, a neurobiologist at Washington university in St. Louis, Missouri, who was not part of the study,
said: "The quality of those maps is analogous to what cartographers of the Earth offered as their best versions back in the seventeenth century," implying its significance as a pioneering work. He said the new map would allow researchers to carry out a synthesis of available data, including gene expression, neuroanatomy and neural activity, with regard to different and specific parts of the brain.
Researchers used a special tool called a microtome cut a human brain preserved in paraffin wax into 20-micrometre thick slivers and map its anatomical structure with high resolution
Amunts et al.
According to
Scientific American, one of the authors, Alan Evans, a neurobiologist at the Montreal Neurological Institute, McGill University, Canada, said at a press conference on 19 June: "This completely changes the game in terms of our ability to discriminate very fine structural and physiological properties of the human brain."
Christof Koch, chief scientific officer at the
Allen Institute of Brain Science in Seattle, Washington, said the quality of the atlas was very high. The Allen Institue also maintains its own atlas of the human brain which also provides structural details of the human brain, but at a lower resolution
The atlas could contribute to projects aimed at modelling the brain. The BigBrain project is part of a larger project, the
Human Brain Project, which, according to
Digital Journal, is a project aimed at creating a "silicon based brain," a supercomputer simulation of the human brain.
According to study author Karl Zilles of the Juelich-Aachen Research Alliance, during a press briefing: "The BigBrain is the first ever brain model in 3D which really presents a realistic human brain with all the cells and all the structures of a human brain."
It could help neurosurgeons in the placement of electrodes for deep brain stimulation, a procedure that
Digital Journal reports is used for treating tremors associated with Parkinson's disease.
According to Van Essen, although BigBrain's data pertains to the brain of only one subject it would serve as a reference for future projects which researchers hope will help to elucidate the differences between brains of different people. According to
Live Science, Koch said: "It's just like a map of a country. If we want to know where to go, it's important to know the lay of the land."
According to
Nature, new advancements in technology since BigBrain project began in 2003 now makes it possible for researchers to scan brain sections at an even finer resolution of one micrometer. However, a new atlas constructed at such a resolution would create about 20,000 trillion bytes of data which is more than the most advanced supercomputers now available can handle.
Sean Hill, executive director of the International Neuroinformatics Coordinating Facility in Stockholm, said: "The technology is continuing to grow rapidly. This is an example of something that is only going to increase in frequency."
German neurobiologist Korbinian Brodmann, produced the first comprehensive brain map early in the 20th century. His map revealed the brain's detailed anatomical structure in only two dimensions.
