With more than 100 billion neurons and 200 billion cells, “the human brain”, Professor Kwanghun Chung explained to Interesting engineering, “is one of the most complex systems in the universe.”
The brain becomes more and more complex as thinking evolves. Each neuron forms tens of thousands of unique functional connections with other neurons. And of course, no two brains are the same. Oh, and brains are plastic, they change.
Important steps have been taken to crack, even if it’s more about slicing, opening the brain to take a photo. However, due to its complexity, neuroscience has failed to penetrate the “intact” brain. Until now. A team from MIT has just done it.
Kwanghun Chung, associate professor in the Picower Institute for Learning and Memory, the departments of Chemical Engineering and Brain and Cognitive Sciences, and the Institute of Medical Engineering and Sciences at MIT, said stated that historically the human brain has been studied using two main technologies. :
“Non-invasive in vivo imaging technologies, such as MRI, and light microscopy combined with molecular labeling methods, such as immunohistology.”
However, both technologies are inherently flawed, so to map the brain, Chung and his team of innovators had to update the technology.
Mapping the brain to understand brain function and dysfunction
In addition to billions of cells and neurons, scientists estimate that there are thousands of different types of neuronal cells in the human brain.
“To understand brain function and dysfunction,” Chung said, “we need to know how these cells are organized in three dimensions and how they interconnect.”
“Preserving and extracting this 3D information requires intact 3D tissues.”
However, previously, imaging the brain at subcellular resolution was not possible without first cutting the brain.
“Human brains are too large to be imaged in their entirety using optical imaging techniques,” Chung continued.
But cutting an entire hemisphere of the brain can not only damage the tissue, but can take months because “the slices have to be very, very thin.”
This represented a first challenge, or an opportunity to innovate in terms of technology.
Entire hemispheres of the human brain have been mapped
MIT created a “technology pipeline,” a set of data processing elements, that successfully captured complete hemispheres in two donated brains, one of which had Alzheimer’s disease.
They have produced three technologies that can “potentially,” according to Chung, completely map the human brain.
They have not yet captured an entire human brain, but they have “achieved holistic imaging of human brain tissue at multiple resolutions, from single synapses to entire brain hemispheres.”
From “vast landscapes of thousands of neurons” to “diverse forests of calls, each in individual detail” to “clumps of subcellular structures nestled among extracellular molecules,” never before has such a detailed picture of the brain been available. been produced. Look at:
MIT did not innovate ONE technology but three
Professor Chung tapped three “particularly talented young scientists” also accredited as co-lead authors of the paper just published in Science because each has produced three major innovations to achieve this feat in neuroscience.
Ji Wang created the “megatome” that severs intact human brain hemispheres without damaging the tissue. Previously, it took months to cut out a hemisphere of the brain, but she has improved the design of this type of vibratome slicer so that no anatomical information is lost in the process.
Once the wafer itself was viable, the next step required an expert chemist, Juhyuk Park. He developed “mELAST,” a technology that makes “each slice clear, flexible, durable, expandable and labelable quickly, evenly and repeatedly.”
By making the slicer itself, the Megatome, more efficient, they were able to take thicker “slices” of the brain. But this would not have been possible without mELAST, because these technologies work together. MELAST is a hydrogel that makes the brain sample clear and indestructible and also allows them to focus on areas of interest.
Once each tile was imaged, they needed computing power to bring this information to life in 3D. Webster Guan provided this system: UNSLICE.
It reconstructs 3D images from individual tiles to the intact brain with cellular connectivity information restored “down to the precise alignment of individual blood vessels and neural axons,” as explained in a press release.
Technology pipeline opens new doors to study brain pathology
The study showcases the robust capabilities of the revolutionary technology pipeline. This suite of innovations allows neuroscientists to take a holistic picture of a hemisphere, zoom in to the subcellular level, map the brain, and understand brain pathology like never before.
Neuroscience can now fully visualize entire hemispheres of the human brain; they updated the technology. Thanks MIT. They were able to study Alzheimer’s disease in a new and astonishing level of detail, identifying the location of the majority of neuron loss in the brain. Thanks again.
And even better, bonus: the technology can be used on other fabrics.
They have just published their study which presents their revolutionary “suite of innovations” in Science.
ABOUT THE PUBLISHER
Maria Mocerino Originally from Los Angeles, Maria Mocerino has been published in Business Insider, The Irish Examiner, The Rogue Mag, Chacruna Institute for Psychedelic Plant Medicines and now Interesting Engineering.