Science
US Scientists Unveil Most Detailed Circuit Map of a Mammalian
Our brain is a mystery—every thought, every emotion, every memory is born within it. But how does it all happen? Now scientists have taken a most remarkable step to find the answer to this question. Scientists have created the most detailed circuit diagram of a tiny layer of the brain of a mammal—a mouse—that will help us understand how our brain actually works.
A region as small as a grain of sand but full of depth
This map is of a tiny part of the mouse’s visual cortex, which is smaller than a grain of sand, but inside it scientists have found 84,000 neurons and more than 500 million synapses. In total, it contains about 5.4 kilometers of neural wiring—all this in a fraction of a cubic millimeter!
Through this 3D reconstruction, scientists are trying to understand how the brain is structured and how different cells work together. This research will not only help in understanding intelligence and consciousness but can also be important in reaching the root of diseases like Alzheimer’s, Parkinson’s, autism and schizophrenia.
A historic moment for neuroscience
This research was carried out under the MICrONS project run by the US intelligence agency IARPA. Dr. David Markowitz, a former program manager associated with this project, considers it a historic and revolutionary moment for neuroscience, like the “Human Genome Project.”
The purpose of this project was not only to see the structure of neurons but also to understand how they communicate with each other. That is, to uncover the ‘secret conversation’ happening inside the brain.
The flight of science crossing the limits of technology
This unprecedented project started at Baylor College of Medicine in Texas, USA. Scientists first recorded the brain activities of that area with the help of a special microscope when the rat was watching YouTube clips and movies.
After this, scientists at the Allen Institute in Washington cut the same cubic millimeter part of the brain into 25,000 very thin layers. Each layer was so thin that it was one-fourth the thickness of a human hair. Then, high-resolution pictures of each layer were taken with the help of an electron microscope.
These pictures were converted into a three-dimensional (3D) map by scientists at Princeton University with the help of artificial intelligence and machine learning. The size of this entire data set is 1.6 petabytes, which is equivalent to about 22 years of non-stop HD video!
The magical forest inside the brain
Dr. Clay Reed, senior neurobiologist at the Allen Institute, says, “Inside that small part, there is a complete internal structure like a beautiful forest.” He also told us that this map contains all the rules and principles that were known from different places in neuroscience until now. Now, through this reconstruction, old theories can be tested and perhaps some new mysteries will also be revealed.
New discoveries: complex collaboration and coordination
This study has revealed new cell types in the brain and a new concept of inhibition. It was previously thought that inhibitory cells—which block neural activity—just slowed down the activity of other cells in a simple way. But this study indicated that these cells are highly selective and decide which cells to affect. This means that the system that inhibits activity in the brain is also highly organized and cooperative.
Revolution in the understanding of brain disorders
A deeper understanding of this kind of structure and function could help get to the root of brain disorders that are caused by impaired communication—such as Alzheimer’s, autism or schizophrenia.
“If you have a radio that breaks down and you have a circuit diagram of the inside, it’s much easier to fix it,” says Dr. Nuno da Costa, associate investigator at the Allen Institute. Similarly, this new Google Map will act as a blueprint for the brain. In the future, we will be able to use it to compare the wiring of a sick mouse brain with that of a healthy brain.
Conclusion: One more step towards the mysteries of the brain
This research series published in the journal Nature has proved that today’s technology and the hard work of scientists can together reveal even the most complex mysteries of the brain. This is not just a map—it is a direction for future treatments, a hope, and a glimpse of the magical machinery that runs inside all of us.
FAQs
Q. What did scientists create?
A. Scientists created the most detailed 3D map of a small part of a mouse’s brain.
Q. Why is this brain map important?
A. It helps us understand how the brain works and how different brain cells communicate.
Q. How small is the brain area they studied?
A. It’s smaller than a grain of sand but contains 84,000 neurons and 500 million connections.
Q. How can this research help people?
A. It could lead to better understanding and treatment of brain disorders like Alzheimer’s and autism.
Q. Who worked on this project?
A. Scientists from the U.S., including teams from Baylor College, the Allen Institute, and Princeton University.
