Supercomputer Fugaku Unveils Unprecedented Brain Map: 10 Million Neurons Simulated

On November 17, 2025, scientists announced the creation of the most detailed brain map ever produced. This remarkable digital simulation, powered by Japan's supercomputer Fugaku, represents almost 10 million neurons, 26 billion synapses, and 86 interconnected brain regions.

The vibrant, color-coded image provides an unprecedented view of the mouse cortex, the brain's outermost layer responsible for critical functions like visual processing, body movement, and decision-making. Each region is depicted as a dense forest of neurons, with the active cells flashing white as they transmit electrical and chemical signals.

Researchers believe this virtual brain model will revolutionize the study of neurological conditions. Until now, understanding the complex interactions within the brain required experimenting on real tissue, one step at a time. But with Fugaku's immense computational power, scientists can now simulate spontaneous brain activity and observe how diseases, seizures, and neural waves spread through the entire system.

"Modeling is incredibly important, because the brain is too complex a system to use your intuition to figure out how cells should be behaving," explained Dr. Tim Jarsky of the Allen Institute. "Even with the subset of kinds of neurons in this dataset, we have so many possible interactions with many different types of signaling. You really need a model to understand how the circuit could behave when you put all those elements together."