Atomic bomb tests confirm formation of new brain cells

A 15 kiloton explosion at the US' Nevada test site.

Nevada.gov

Researchers have used the radioactive fallout from atomic bomb tests to show that new neurons are produced in one part of the human brain throughout life. Studies have shown that rats can grow new neurons, but there was little definitive evidence that it happens in humans too.

When atomic bombs were tested between 1945 and 1963, radioactive particles were released into the Earth’s atmosphere. Among the isotopes created was carbon-14, which is commonly used in radio carbon dating.

As cells divide, they incorporate carbon from the environment, and some of that carbon comes from the atmosphere. That's why carbon-14 released by the atomic bombs found its way into the DNA of multiplying cells. The amount of carbon-14 in this DNA corresponded to its concentration in the atmosphere at the time the new cells were born.