Thanks to a mouse viewing segments from 'The Matrix,' Scientists have developed the most extensive functional map of a brain so far — an illustration depicting how 84,000 neurons connect as they transmit signals.
With just a tiny section of the mouse’s brain, roughly the size of a poppy seed, scientists were able to pinpoint these specific neurons and map out their communication pathways across an unexpected 500 million synaptic connections.
The extensive data set, released on Wednesday in the journalNature, represents progress towards solving the puzzle of understanding how our brains work.
The information, presented as a color-coded 3D reconstruction highlighting various neural pathways, is available globally for further study by researchers and can also be explored by those who are merely interested.
"Forrest Collman from the Allen Institute for Brain Science in the U.S., a key researcher in this project, remarked that 'it certainly evokes a feeling of wonder, much like viewing images of distant galaxies,' " he stated.
You start to grasp your own intricacy. We're examining just a small section of a mouse's brain, yet the elegance and complexity evident in these individual neurons and their countless millions of interconnections are astounding.
Our thoughts, emotions, perceptions, speech, and movements result from the activity of neurons, which are nerve cells in the brain—how they get triggered and communicate with one another.
Scientists have been aware for a long time that these signals travel through neurons via structures called axons and dendrites, utilizing synapses to transfer to the following neuron.
However, much remains unknown regarding the neuronal networks responsible for specific functions and how alterations in their connectivity might contribute to various issues. Alzheimer's , such as autism or other conditions.
In the latest initiative, over 150 scientists from around the world collaborated to chart neuronal pathways within a section of the mouse brain associated with vision. These connections were likened by Collman to strands of spaghetti intertwined in an intricate network.
In what manner did researchers chart the human brain?
Step one involves displaying short clips from science fiction films, sporting events, animated shows, and documentaries about nature.
Researchers at Baylor College of Medicine in the United States achieved this by employing a genetically modified mouse whose neurons emit light when activated.
The scientists employed a laser-driven microscope to capture the activity of individual cells within the creature's visual cortex as these cells responded to rapidly presented images.
Following this, researchers from the Allen Institute examined that section of brain tissue with a specialized device that sliced it into over 25,000 sections and captured approximately 100 million high-resolution photographs utilizing electron microscopes. Afterward, they meticulously reconstructed these images into a three-dimensional model.
In conclusion, researchers at Princeton University in the United States employed artificial intelligence (AI) to map out all those connections and "assign a distinct color to each wire so they can be identified individually," as stated by Collman.
They calculated that if the tiny wires were stretched out, they would extend for over 5 kilometers.
Implications for human health
Could this kind of mapping assist researchers in ultimately discovering cures for neurological disorders?
The researchers refer to this as a crucial milestone, similar to how the Human Genome Project, which offered the initial genetic map, ultimately paved the way for therapies based on genes.
One of the upcoming objectives is to map an entire mouse brain.
"The innovations from this initiative will provide our initial opportunity to genuinely detect an unusual pattern of connectivity that leads to a disorder," stated Sebastian Seung, a Princeton neuroscientist and computer scientist and one of the key investigators for the project.
"The effort represents a significant advancement and provides an indispensable communal asset for upcoming breakthroughs," noted Harvard neuroscientists Mariela Petkova and Gregor Schuhknecht, who were not part of this initiative.
The extensive and collectively accessible data "will aid in deciphering the intricate neurological networks that underlie thought processes and actions," they mentioned additionally.