The brain has 5 developmental stages, but 'adulthood' doesn't begin until age 32, scientists say

The brain has five major structural phases during the human lifespan and doesn't reach adulthood until age 32, a new study suggests.

Scientists determined that brain development is defined by four "turning points" — at ages 9, 32, 66 and 88 — by analyzing brain scans from more than 3,800 people ages 0-90. Their findings, published Tuesday in Nature Communications , could have implications for better understanding issues that affect brain health at different stages of life, the researchers said. MORE: Nearly 1 in 10 American adults say they've received a cancer diagnosis

"Understanding that the brain's structural journey is not a question of steady progression, but rather one of a few major turning points, will help us identify when and how its wiring is vulnerable to disruptio