[LifeStyle] How do brains coordinate activity? From fruit flies to monkeys, we discovered this universal principle

[HoldFire 流]

The brain is a marvel of efficiency, honed by thousands of years of evolution so it can adapt and thrive in a rapidly changing world. Yet, despite decades of research, the mystery of how the brain achieves this has remained elusive. Our new research, published in the journal Cell, reveals how neurons – the cells responsible for your childhood memories, thoughts and emotions – coordinate their activity. It’s a bit like being a worker in a high-performing business. Balancing individual skills with teamwork is key to success, but how do you achieve the balance? As it turns out, the brain’s secret is surprisingly simple: devote no more than half (and no less than 40%) of each cell’s effort to individual tasks. Where does the rest of the effort go? Towards scalable teamwork. Advertisement And here’s the kicker: we found the exact same organisational structure across the brains of five species – from fruit flies and nematodes to zebrafish, mice and monkeys. These species come from different branches of the tree of life that are separated by more than a billion years of evolution, suggesting we may have uncovered a fundamental principle for optimised information processing. It also offers powerful lessons for any complex system today. Festive offer The critical middle ground Our discovery addresses a long-standing debate about the brain: do neurons act like star players (each highly specialised and efficient) or do they prioritise teamwork (ensuring the whole system works even when some elements falter)? Answering this question has been challenging. Until recently, neuroscience tools were limited to either recording the activity of a few cells, or of several million. It would be like trying to understand a massive company by either interviewing a handful of employees or by only receiving high-level department summaries. The critical middle ground was missing. Advertisement However, with advances in calcium imaging, we can now record signals from tens of thousands of cells simultaneously. Calcium imaging is a method that lets us watch neural activity in real time by using fluorescent sensors that light up according to calcium levels in the cell. Applying insights from my physics training to analyse large-scale datasets, we found that brain activity unfolds according to a fractal hierarchy. Cells work together to build larger, coordinated networks, creating an organisation with each scale mirroring those above and below. This structure answered the debate: the brain actually does both. It balances individuality and teamwork, and does so in a clever way. Roughly half of the effort goes to “personal” performance as neurons collaborate within increasingly larger networks.