Scientists are seeking ways to stave off neurodegenerative disorders like Alzheimer’s. And in their search for clues, they’ve set their sights on a select cohort known as “superagers.”
Age remains the chief predictor of Alzheimer’s, and as the world’s population skews older, dementia rates are rising: Globally, cases are expected to triple by the year 2050. Scientists are seeking ways to stave off neurodegenerative disorders like Alzheimer’s. And in their search for clues, they’ve set their sights on a select cohort known as “superagers.”
Coined by the Northwestern SuperAging Research Program, “superagers” are people in their 80s and 90s exhibiting exceptional cognitive prowess — and vibrant social engagement. The term is not an official scientific designation, but it has proven key to the question of what makes someone resilient against cognitive decline. So, what sets superagers apart from the rest?
In one recent study, scientists studied the brains of 102 deceased superagers who were all aged 97 at the time of death, and who had performed well in cognitive tests in their last year of life. Some of these 97-year-olds did, it turned out, have the hallmark beta-aymloid plaques that appear in Alzheimer’s disease. And yet, they never developed symptoms. Here are three of the current theories as to why superagers remain resilient.
1. Superagers’ brains don’t gradually shrink as much as other people’s brains do
Superagers appear to defy the typical trajectory of brain shrinkage observed in aging individuals. Notably, the cingulate cortex, crucial for memory and cognitive functions, displays resistance to atrophy. A 2013 study at Northwestern University looked at the brains of superagers versus the general population and found structural disparities in this brain region, suggesting it could house a possible shield against Alzheimer’s-related decline.
Now, some scientists are asking: Could preventing the cingulate cortex from shrinking be a way to help prevent age-related memory loss down the road?
2. Superagers have a lot of mysterious, giant von Economo neurons
Another unique finding within superagers’ brains is the heightened presence of von Economo neurons: They have three to five times more of this brain cell than other people. These specialized neurons may die off over the course of mild cognitive impairment and Alzheimer’s disease. Researchers are investigating: Could starting with more of these von Economo neurons give superagers a longer runway when it comes to maintaining cognitive health well into old age?
3. Superagers are socially, mentally, and physically active — and that might protect their brain health
The vitality of superagers transcends biology: They’re known for robust social, mental, and physical engagement — and that could be part of the answer to how they stay so cognitively healthy for so long.
Because superagers lead rich social lives well into their 80s and 90s, and studies show that mental and physical activities — like cooking or dance classes — keep the brain active, it’s possible these things might all be interconnected. This tendency to be socially and intellectually engaged might even play a role, some scientists think, in stimulating the cingulate cortex and the von Economo neurons.
Another recent study found that superagers also tend to move faster than other older people their age, irrespective of how often they exercise, and also tend to have better mental health — which could be related to their rich social lives.
While the causality between an active lifestyle and brain health is still not totally understood, evidence suggests that embracing social and physical activities could mitigate the risk of cognitive decline.
There’s a “chicken and egg” aspect at work here, as staying active could preserve health, but it also takes cognitive and physical health to stay active. Still, making an effort to exercise and be social is one of those modifiable lifestyle factors that research indicates could help to protect the brain from disease.