This isn't a galaxy — it's a map of a mouse's brain

The Associated Press

· Posted: Apr 10, 2025 3:50 PM EDT | Last Updated: 19 minutes ago

Thanks to a rodent watching clips from The Matrix, scientists person created the largest functional representation of a encephalon to day — a diagram of the wiring connecting 84,000 neurons arsenic they occurrence disconnected messages.

Using a portion of that mouse's encephalon astir the size of a poppyseed, the researchers identified those neurons and traced however they communicated via branch-like fibres done a astonishing 500 cardinal junctions called synapses.

The monolithic dataset, published Wednesday by the diary Nature, marks a measurement toward unravelling the enigma of however our brains work. The data, assembled successful a 3D reconstruction, coloured to delineate antithetic encephalon circuitry, is unfastened to scientists worldwide for further probe — and for the simply funny to instrumentality a peek.

"It decidedly inspires a consciousness of awe, conscionable similar looking astatine pictures of the galaxies," said Forrest Collman, of the Allen Institute for Brain Science successful Seattle, 1 of the project's starring researchers.

"You get a consciousness of however analyzable you are. We're looking astatine 1 tiny part … of a mouse's brain, and the quality and complexity that you tin spot successful these existent neurons and the hundreds of millions of connections betwixt them."

How we think, feel, see, speech and determination are owed to neurons, oregon nervus cells, successful the brain: how they're activated and nonstop messages to each other. Scientists person agelong known those signals determination from 1 neuron on fibres called axons and dendrites, utilizing synapses to leap to the adjacent neuron. But there's little known astir the networks of neurons that execute definite tasks and however disruptions of that wiring could play a relation successful Alzheimer's, autism oregon different disorders.

"You tin marque a 1000 hypotheses astir however encephalon cells mightiness bash their job, but you can't trial those hypotheses unless you cognize possibly the astir cardinal happening — however are those cells wired together," said Allen Institute idiosyncratic Clay Reid, who helped pioneer electron microscopy to survey neural connections.

Uncrossing the wires

With the caller project, a planetary squad of much than 150 researchers mapped neural connections that Collman compares to tangled pieces of spaghetti winding done portion of the rodent encephalon liable for vision.

The archetypal step: Show a rodent video snippets of sci-fi movies, sports, animation and nature.

A squad astatine Baylor College of Medicine did conscionable that, utilizing a rodent engineered with a cistron that makes its neurons glow erstwhile they're active. The researchers utilized a laser-powered microscope to grounds however idiosyncratic cells successful the animal's ocular cortex lit up arsenic they processed the images flashing by.

WATCH | Allen Institute video reveals largest wiring diagram and functional representation of the brain:

Next, scientists astatine the Allen Institute analyzed that tiny portion of encephalon tissue, utilizing a peculiar instrumentality to shave it into much than 25,000 layers, each acold thinner than a quality hair. With electron microscopes, they took astir 100 cardinal high-resolution images of those sections, illuminating those spaghetti-like fibres and painstakingly reassembling the information successful 3D.

Finally, Princeton University scientists utilized artificial quality to hint each that wiring and to "paint each of the idiosyncratic wires a antithetic colour truthful that we tin place them individually," Collman explained.

They estimated that microscopic wiring, if laid out, would measurement much than 5 kilometres. Importantly, matching up each that anatomy with the enactment successful the mouse's encephalon arsenic it watched movies allowed researchers to hint however the circuitry worked.

WATCH | MICrONS consortium video explores the connections of the brain: 

The Princeton researchers besides created integer 3D copies of the information that different scientists tin usage successful processing caller studies.

Could this benignant of mapping assistance scientists yet find treatments for encephalon diseases? The researchers telephone it a foundational step, similar however the Human Genome Project that provided the archetypal gene-mapping yet led to gene-based treatments. Mapping a afloat rodent encephalon is 1 adjacent goal.

"The technologies developed by this task volition springiness america our archetypal accidental to truly place immoderate benignant of abnormal signifier of connectivity that gives emergence to a disorder," different of the project's starring researchers, Princeton neuroscientist and machine idiosyncratic Sebastian Seung, said successful a statement.

The enactment "marks a large leap forward and offers an invaluable assemblage assets for aboriginal discoveries," wrote Harvard neuroscientists Mariela Petkova and Gregor Schuhknecht, who weren't progressive successful the project.

The immense and publically shared information "will assistance to unravel the analyzable neural networks underlying cognition and behaviour," they added.

The Machine Intelligence from Cortical Networks, oregon MICrONS, consortium was funded by the U.S. National Institutes of Health's BRAIN Initiative and IARPA, the Intelligence Advanced Research Projects Activity.