Nearly a quarter of the changes often seen in a person’s intelligence level over the course of a lifetime may be due to genes, a proportion never before estimated, new research shows.
The study suggests that genes may partly explain why some people’s brains age better than others, even though environmental factors likely play a greater role over a lifetime.
Understanding the factors behind healthy mental aging has become an increasingly vital one for societies with large elderly populations. However, it isn’t an easy task.
Traditional methods of estimating the influence of genes and the environment on intelligence have largely been limited to comparisons between people who are related, such as identical or fraternal twins. The shortcoming of such studies is they didn’t clearly apportion the effects of each factor on intelligence.
More of the WSJ article from Gautam Naik