IQ is not fixedChompoo Suriyo/Shutterstock
Although the origins of intelligence are still being researched, it does seem clear that IQ, or intelligence quotient, is not fixed—it can change throughout your life. In fact, some experts argue that there’s no such as thing as “IQ” at all, but that experiences and learning, as well as the testing itself, are variable and can change over time. Studies show our nutrition and other environmental factors may also impact brain power. “We used to think that once smart, always smart and vice versa—we now know that is wrong,” says Sandra Bond Chapman, PhD, founder and chief director of the Center for BrainHealth at the University of Texas at Dallas. “Science clearly reveals that the brain and our ‘smartness’ are anything but fixed. We continuously shape and rewire our brain by how we think.” That’s one of the reasons you shouldn’t tell your children they’re smart
The brain changes as it ages
It’s true that certain aspects of our noggin change—some for the worse—as we age. “As we age, our brains normally shrink in size by about one to two percent every year after the age of 40,” Dr. Tarawneh says. “This occurs due to loss of brain cells, brain cells shrinking in size, and also some loss of the branches that neurons use to communicate with each other, referred to as dendrites.” But, the brain also improves as we age. Recent research has some good news—more than one-third of the neurons in the hippocampus are regularly renewed throughout life, according to a Swedish study. Learn how to recognize the 12 signs your brain is aging faster than you are.
In some ways we get smarter as we agemimagephotography/Shutterstock
Dr. Tarawneh points out that although some mental processes decline as we age, not all do. “Some of our brain functions such as short-term memory for minor details, processing speed, attention, the ability to multi-task, and visuospatial functions show some decline with healthy aging,” she says. “On the other hand, language functions tend to remain well-preserved as we get older.” In fact, research from Harvard and MIT show that arithmetic skills don’t peak until age 50, and vocabulary and “cumulative intelligence” (all the facts and knowledge you’ve acquired) peak even later, into our early 70s. To keep your brain young, start these habits your 80-year-old brain will thank you for doing today.