Brain connectivity undergoes four major structural shifts during life

A large-scale analysis of thousands of brain scans has revealed that the human brain's structural network does not develop in a steady, linear curve. Instead, neuroscientist Alexa Mousley from the University of Cambridge found that the brain undergoes significant restructuring at four distinct turning points throughout a person's life.

Rather than a continuous rise and fall, the brain's connections change in marked shifts. For example, during puberty, a process known as synaptic pruning occurs, where less-used connections are eliminated to create a more streamlined, specialized, and efficient network.

This structural evolution correlates with changes in cognitive abilities. While fluid intelligence—the capacity to analyze new problems and think abstractly—typically peaks in youth and early adulthood, crystallized intelligence, which relies on accumulated knowledge and experience, continues to grow throughout life.