The nature of intelligence isn’t knownDean Drobot/Shutterstock
You can fake being smart (especially with these easy ways to look like a genius), but what really makes us intelligent, if not brain size and folds? “Although we still do not know all of the biological processes that explain intelligence, intelligent people probably have better connections between the neurons, referred to as synapses, and their neurons have stronger networks in certain brain regions that allow the brain cells to communicate with each other more efficiently,” Dr. Tarawneh says. She notes that anatomy may have something to do with it, as some studies suggest more intelligent people may have thicker cortices (the outer part of the two hemispheres), particularly in some parts such as the parietal lobe.
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.