A collaborative international team has used Japan’s Fugaku supercomputer—one of the world’s most powerful systems—to create the first biophysically detailed, whole-cortex simulation of the mouse brain at near-cellular resolution. The model encompasses approximately 10 million neurons, 26 billion synapses, and 86 interconnected cortical regions, incorporating precise ion-channel dynamics, membrane voltages, and synaptic transmission mechanisms.
Running on Fugaku, hosted at the RIKEN Center for Computational Science in Kobe, the simulation spontaneously generates realistic resting-state neural activity that closely matches experimental recordings from living mice. This emergent behavior validates both the accuracy of the underlying biological data and the scalability of the computational framework, which combines the Allen Institute’s Brain Modeling ToolKit with custom high-performance software.
The breakthrough dramatically expands the scope of in silico neuroscience, enabling researchers to study network-level phenomena—such as wave propagation, oscillatory dynamics, and the impact of genetic mutations—across an entire cortical system for the first time. Such digital models offer a powerful complement to wet-lab experiments and may substantially reduce future reliance on animal studies.
With this milestone now demonstrated on Japanese supercomputing infrastructure, the path is clear for rapid progression toward full mouse-brain simulations and, within the coming decade, human whole-brain models that could transform fundamental neuroscience and accelerate therapeutic discovery.
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