By mapping a tiny part of the human brain, Google researchers have revealed details of our encephalon with breathtaking precision. An exploration into the heart of the infinitely small.
Google is once again interested in our brain, but this time, in a completely different way. In a study recently published in Scienceresearchers from the American company, led by Viren Jain (neuroscientist at Google) unveiled a three-dimensional map detailing a volume of approximately one mm3 of a human brain. An unprecedented scientific feat, thus shedding light on all the neuronal entanglements and their complex connections.
A real cellular atlas
The brain fragment, taken from a 45-year-old woman during an operation to treat her epilepsy, was preserved and treated with heavy metals to facilitate observation under a microscope. This sample was then cut by the team of Professor Jeff Lichtman of Harvard University into approximately 5,000 slices with an incredibly thin thickness of 34 nanometers, allowing detailed imaging to be carried out on them using microscopes. electronic.
Dr. Jain’s team then carried out a full 3D reconstruction of the neural network, using artificial intelligence models which allowed the assembly of these ultra-precise images. This technological feat revealed a dense network of 57,000 cells and 150 million synapses, providing unprecedented insight into the structure and connectivity of the human brain. The map created by the team contains 1.4 petabytes of data!
Our brain still has a few surprises in store for us
This mapping revealed extraordinary details regarding the neuronal organization within a fragment of the human brain. Among these discoveries, we can cite the observation of certain nerve cells establishing up to 50 synaptic connections between them. This number of connections, significantly higher than what has been observed until now (where we typically found only a few connections between two neurons), proves that we are still far from understanding everything about brain functioning.
Alongside this discovery, Dr. Jain’s team highlighted the existence of neurons whose dendrites form knotted structures, a completely new observation to date. These nodes could suggest the existence of complex or new neuronal functions, still unexplored by neurological sciences.
This mapping will prove to be a valuable scientific tool for years to come and will be used to decipher the internal functioning of our brain more precisely. We can also imagine that it will be a valuable ally in improving our understanding of neurodegenerative diseases and other psychiatric conditions.
Sources: Nature, Science
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