Researchers at the University of Cambridge mapped the brain's wiring in over 4,000 people from birth to age 90, using diffusion imaging that tracks how water moves along nerve fibers, then looked for the moments the pattern changed direction.
Instead of one smooth curve, the data broke into five distinct stretches, with turning points clustering around ages 9, 32, 66 and 83. Each turning point marked a shift in how efficiently different brain regions stayed connected to each other, not just how big or small any single region was.
The turning point near age 9 lined up with the rise in mental health risk as childhood gives way to adolescence, and the one near 66 with the early-60s rise in high blood pressure and dementia, suggesting the brain's wiring reorganizes itself at points that matter for disease, not just for aging on a graph. The data came from one large analysis, and whether the exact ages hold up across different populations is the next question.
Read the original study
Mousley et al., Nature Communications, 2025 · doi.org/10.1038/s41467-025-65974-8
A life has chapters, not a slope.
Source
- Mousley, A., Bethlehem, R. A. I., Yeh, F.-C., & Astle, D. E. (2025). Topological turning points across the human lifespan. Nature Communications, 16(1), 10055. https://doi.org/10.1038/s41467-025-65974-8