Cambridge Study Maps Four Brain Turning Points Across Lifespan

Scientists at the University of Cambridge have identified four key turning points in the human brain's structural development across the lifespan, marking shifts into five distinct epochs of neural wiring. The study, published Tuesday in the journal Nature Communications, analyzed MRI diffusion scans from 3,802 individuals aged from birth to 90, revealing how the brain reconfigures its connections to support evolving ways of thinking and processing information.

The turning points occur at approximately ages 9, 32, 66 and 83, according to lead author Alexa Mousley, a postdoctoral researcher at Cambridge. These phases challenge the notion of a linear progression in brain development, where cognition steadily rises to a peak and then declines. Instead, the research shows periods of rapid change, stabilization and eventual fragmentation.

In the first epoch, from birth to age 9, the brain undergoes network consolidation. Excess synapses, the connections between neurons overproduced in infancy, are pruned, leaving the most active ones to strengthen. Grey matter, which processes information, and white matter, which facilitates communication, expand rapidly. Cortical thickness peaks,...