The secrets to keeping your brain sharp in old age

As you age, your memory will likely decline. Your ability to recall where you parked the car or the name of your first teacher will be less sharp in your 80s than in your 50s, if you’re in the majority of people. But a small pool of individuals in their 80s and beyond don’t experience this downturn: they have a memory that rivals that of people decades younger. It is this group that Emily Rogalski is interested in.

Rogalski, a neuroscientist at the University of Chicago and head of the ongoing superager study, is unpicking how these people manage to stay so sharp, even if they have signs of Alzheimer’s disease in their brain. Rogalski and her colleagues have already shown that so-called superagers have larger cerebral cortices and hippocampi, both areas of the brain associated with memory, and are now working to unravel the neural basis of their recall abilities. She tells New Scientist what makes someone a superager, and how you can boost your chances of becoming one.

Alexandra Thompson: What is a superager?

Emily Rogalski: A superager is an individual who is over 80 but has a memory that is at least as good as individuals’ in their 50s or 60s. Their other cognitive domains of language, like executive function and attention, need to be at least average for their age. Nearly everyone I run into can think of at least one person in their life – whether it’s an aunt, uncle, neighbour or friend – who you would never believe is 90. They act like they’re 50.

We hear reports of older people achieving phenomenal physical feats, like centenarians running marathons. Why are you focusing on what it takes to have an extraordinary memory over other traits?

Memory loss is the number one thing that older adults complain about as they get older, and it is also the cardinal symptom of Alzheimer’s. As a neuroscientist, that’s what I’m interested in. Individuals who have an extraordinary memory over the age of 80 have surpassed the biggest risk for Alzheimer’s, which is getting older. One way to study Alzheimer’s disease is to look at what’s going wrong and try to reverse it. The other is to identify people who are avoiding age-related memory loss, and in fact are thriving, and say, “How did you do that?”

How do you find these people?

We spend a lot of time in the community, like farmers’ markets and retirement communities, where we give lectures on healthy ageing, and that’s where you can meet these people. It is also through word of mouth – some of our superagers are good at finding other superagers. We started off just enrolling from the Chicago area, but now we’re across five sites in the US and Canada, which allows for [not only] regional representation, but also racial and ethnic representation.

How do you assess candidates to make sure they qualify for superager status? And then, how are they involved in your research?

When a prospective superager comes in, they do cognitive tests, surveys, [and] have a clinical interview and a brief neurological exam. They also have an MRI scan of their brain, and they have a blood draw to look at genetic factors. They often didn’t know that they had an extraordinary memory, or reported not having it all their lives, but then they are very proud.

And we always say that they’re with us for life and beyond, because they don’t just come in for those initial visits; they come back every two years. They also participate in check-in phone calls every six months, and we ask them to donate their brain at the time of death, which allows us to look at cellular and molecular factors that we can’t readily get at during life.

What do the autopsy results generally show?

Overall, there tends to be less tau [a protein that can form tangles, which are thought to contribute to Alzheimer’s disease] in superagers. However, there are individuals who have an abundance of Alzheimer’s-related pathologies, so much so that a neuropathologist might say that this person likely had cognitive impairment. On the flip side, we have some case studies where there’s exceedingly less pathology than we would expect for a 95-year-old.

We know that some people may be genetically protected against developing Alzheimer’s, but it sounds like some of the superagers you see have developed the pathological signs of the disease, without its symptoms.

Back when we started the superagers project, it had been posed to me several times that maybe superagers are just really low-risk for Alzheimer’s, but that’s not what we see. If superagers are inherently protected against Alzheimer’s, then that should theoretically be reflected in their genetics. But when we compare them against cognitively average individuals, we see that the controls don’t significantly differ genetically from the superagers. There are even some people who are at very high risk for Alzheimer’s and are still in that superageing group.

Why is this? Do they have a protective factor that is nullifying their risk? We don’t have a magic recipe, per se, but we have seen unique cellular markers associated with super-ageing. For one, these people have an abundance of a special type of neuron called Von Economo neurons, which have been described in only two regions of the brain. One is the anterior cingulate, and the other is the frontal insular cortex [which has been linked to decision-making]. In the anterior cingulate, there are four to five times the number of these neurons in superagers. And on MRI scans, the anterior cingulate cortex is thicker in superagers than it is in 50-to-60-year-olds. This region is really important for attention, and attention is essential for memory.

When you ask these people about their lifestyles, what comes up?

When I think about the ties that bind superagers, the number one is that they tend to be socially active. If you make it to 111, your peers aren’t alive, so you need to find connection with younger generations to avoid social isolation and loneliness. These individuals find connection. Sometimes that’s with much younger [people] by volunteering in classrooms, and sometimes, if you’re 95, it’s finding connection with somebody who’s 65, who might be in the same retirement community.

Another feature we see is adaptability, grit and resilience. You might assume everyone had life handed to them on a silver platter. That’s not what we see. We have an individual who was the only member of her family who survived the Holocaust. She was in a concentration camp. We have individuals who lost their kids at a young age. They seem to say, “Life has handed me something difficult, but I’m going to bounce back.”

While there’s certainly ample evidence on the importance of diet, this is not consistent among superagers. In fact, many of them will say, “Gosh, it can’t be my diet. I had way too many TV dinners as a child.” Exercising also varies. For some, their exercise might be chair stretching because they need a wheelchair… [then there are other] people who are biking hundreds of miles.

Hearing about someone who survived the Holocaust is very moving.

She is someone who has experienced tremendous pain and hardship, and yet when I met her, when she was aged over 90, she was running the gift shop in her retirement community. She was finding connection. She has a willingness to share stories and learn.

Why is socialising so good for the brain?

Our brain loves nothing more than to do something new and challenging. When we lift weights, we get out of our physical comfort zone, and that’s how we build muscle. We need to do the same with our brain, to keep it active. It’s hard to have a conversation, especially with people you don’t know, but that’s good exercise for the brain.

Some older people seem to really benefit from seeking out the company of much younger individuals. Why is that?

In those instances, you’ve got co-mentorship. The older adults are mentors to the kids, just as much as the kids are mentors to the older adults. I can think of a gentleman who decided to move back in with his daughter, not because he had to physically or mentally, but because he wanted to maintain connection with his grandkids. He said, “I have to remember they don’t know much about Frank Sinatra… so I have to ask them questions like, ‘Is Chance the Rapper coming to town, or Taylor Swift?’” It is another way of staying cognitively and socially engaged.

Could it be that people who are already cognitively sharp are then more able to socialise, rather than socialising making them cognitively sharp?

We have to be very careful in the work we do to understand when something is causal and when two factors are merely associated. Maybe someone is able to stay socially connected because they have their cognitive faculties, but we don’t think that’s all there is to it. We even see that those who stay socially connected in the face of Alzheimer’s tend to decline more slowly.

Sometimes the path to a long, healthy life can feel a bit virtuous: eat well, exercise regularly, don’t smoke, go to bed early. Do superagers indulge from time to time?

Absolutely, sometimes we ask people, “What do you think makes you a superager?” and I remember a pair of friends who enrolled on the project together said, “It’s because we have a martini together every day at 5pm.” That isn’t to endorse alcohol, but it needs to be contextualised. That daily martini is how they are making connections and finding a point of calm.

With all the research you have done into what makes a superager, what advice would you give someone who is hoping to become one?

We used to think of genetics as, “shoot, I picked the wrong parents”, but we now know genetics is much more complex than that. It’s not just about being dealt a lucky hand or an unlucky hand. That hand is somewhat modifiable, and in terms of how, I go back to social connection. If you’re walking home from work, and think, “Should I listen to music or should I call my friend?” I say, call your friend.