I Study Cognition & This Is How To Know How "Old" Your Brain Is

We know that our brains are often not the same age as our chronological age. For instance, there is a group of people called SuperAgers, who are in their 80s and beyond but have the cognitive function of those decades younger1. Conversely, it's possible for your brain to be older than your chronological age.

While there's no test you can take at home to definitively say how "old" or "young" your brain is, we can think of a young and healthy brain as being at peak function. And, most often, peak brain function is associated with a sharp memory. As we get older, it can be difficult to remember names, faces, events, something we just read, or what we ate.

In younger brains, the process called neural differentiation is efficient and robust. In this process, specific brain cells are tasked to remember certain types of information, such as faces. As we age, that process deteriorates, so the cells lose their specificity and do not function as well.

Instead of just focusing on faces, they try to remember other types of information as well. For a SuperAger, neural differentiation is akin to that of a 25-year-old. That's part of the reason why a SuperAger has the memory performance of a 25-year-old.

So what else are the secrets of these SuperAgers with robust memory—and all those with brain ages younger than their chronological age? A study published in 2021 uncovered some surprising answers. Over 18 months, the study followed 330 people, referred to as SuperAgers, who were 100 years or older; the researchers found no decline in most areas of memory or cognitive abilities2.

While a year and a half might not sound like a long time, once a person reaches the century mark, two years for them is like 25 years for a 75-year-old in terms of brain health.

So, what is the secret of these mentally strong centenarians? You might be tempted to guess "genes." While genes can definitely play a role, 16.8% of the people in the study had genes that are known to raise the risk of Alzheimer's, and they did not develop the disease. What seemed to be a key piece of the puzzle was lifestyle!

One key factor was that they kept learning new things throughout their life. Remember, your memories are housed in those connections between your brain cells. Think of your brain like a bank account; the more deposits we make, the less our net worth is affected by withdrawals.

We make deposits (new connections) by learning new things; as we age and naturally lose some of those connections, there are simply more remaining.

While we are not at the point where every person can slide into a brain scanner and find out their brain age, here are just a couple of factors that can help give you a sense of your brain age. Ask yourself the following five questions.

Use this BRAIN mnemonic to quiz yourself tomorrow on these five questions. Mnemonics are an excellent way to remember information. Since recall is a use-or-lose-it skill and one of the five questions, here's a fun chance to practice. 

Of course, none of these questions can replace an actual brain scan and comprehensive evaluation by a neurologist. Still, these fundamental categories can help us get a sense of brain age. It is important to note that simply determining someone's brain age by brain scan is also not without complexity and controversy9.

In all seriousness, determining brain age using cutting-edge imaging technology has become an emerging and powerful tool in research studies at large institutions10 to understand health, disease, and mortality. Remember, it is not just one of these factors but a combination that determines brain age.