Scientists have finally identified what separates the people who arrive at 90 with sharp, reliable memories from those who don’t, and the answer is far more specific than “good genes” or “healthy living.”
A landmark study from Northwestern University’s SuperAging Program, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, followed 290 adults aged 80 and older over 25 years, tracking their cognitive function, scanning their brains, and in 77 cases, examining their donated brains after death.
What the researchers found reshapes everything we thought we knew about aging and the mind.
Some people in their 80s and 90s score just as well on memory tests as healthy adults in their 50s.
Not slightly better than average for their age. On par with people three decades younger.
These individuals have a name. Scientists call them SuperAgers.
What Exactly Is a SuperAger?
The term “SuperAger” was coined by Dr. M. Marsel Mesulam, founder of the Mesulam Center for Cognitive Neurology and Alzheimer’s Disease at Northwestern University, in the late 1990s.
To qualify, a person must be 80 or older and score at least 9 out of 15 on a delayed word recall test, a threshold typically met by people in their 50s and 60s, not their ninth decade.
Think about what that means in practical terms.
An 85-year-old SuperAger hears a list of words, waits a few minutes, and then recalls them with the same accuracy as someone who is 55.
That is not a slight edge. That is a biological gap that, until now, no one fully understood.
How the Study Was Conducted
The Northwestern SuperAging Research Program began enrolling participants in 2000 and has followed them ever since, making it one of the longest-running cognitive aging studies in the world.
Participants undergo annual cognitive evaluations, including memory tests, attention tasks, and neurological assessments.
Their brains are scanned using MRI imaging to measure cortical thickness, volume loss, and structural changes over time.
What makes this research truly rare, and truly powerful, is what happened after participants died.
Seventy-seven SuperAgers chose to donate their brains for postmortem analysis, giving researchers an unprecedented window into the biological differences between an aging brain that holds onto memory and one that does not.
This brain donation component is what elevated the study from interesting to earth-shattering.
Scientists could now physically examine the tissue, measure neuron sizes, count specific cell types, and look for the toxic protein buildup associated with Alzheimer’s disease.
Findings From the Study
The results revealed two distinct biological pathways to becoming a SuperAger, and both of them challenge conventional assumptions about how memory loss happens.
Pathway One: Resistance
Some SuperAgers never accumulated the harmful proteins in the first place.
Their brains showed little to no buildup of amyloid plaques and tau tangles, the toxic proteins widely considered the primary drivers of Alzheimer’s disease.
Their brains simply did not make them, or made so little that there was nothing meaningful to detect.
Pathway Two: Resilience
Other SuperAgers had accumulated these same damaging proteins, but something remarkable was happening.
The proteins were there. The damage, however, was not.
As Dr. Sandra Weintraub, professor at Northwestern University Feinberg School of Medicine and a lead researcher on the study, explained: “One is resistance: they don’t make the plaques and tangles. Two is resilience: they make them, but they don’t do anything to their brains.”
Their brains had found a way to coexist with the very substances that rob millions of people of their memories, and simply carry on.
The Brain Looks Younger, Too
Beyond the protein findings, SuperAger brains also showed striking structural differences.
MRI scans revealed that the cortex, the outermost layer of the brain responsible for thinking and memory, did not thin at the usual rate.
In typical aging, the cortex gradually shrinks. In SuperAgers, it stayed thicker, closer in structure to a brain belonging to someone in their 40s or 50s.
One region in particular stood out: the anterior cingulate cortex, an area deep in the brain connected to attention, decision-making, and emotional regulation. In SuperAgers, this region was not just intact, it was thicker than in average adults decades younger.
Neurons That Are Bigger and More Abundant
The researchers also found differences at the cellular level.
SuperAgers had significantly larger entorhinal neurons, the cells in a region of the brain critical for memory formation.
They also had a far higher number of von Economo neurons, a rare and specialized type of brain cell linked to social processing, awareness, and emotional intelligence.
According to findings published through Northwestern Medicine, SuperAgers have more than four to five times the number of von Economo neurons compared to the average person in their 80s.
These are not small differences. These are the kinds of differences that show up clearly under a microscope and demand an explanation.
What Most People Get Wrong About Memory and Aging
Here is where the science takes a genuinely surprising turn.
Most people, when they think about protecting memory as they age, picture the usual checklist: eat well, exercise regularly, sleep enough, maybe do a crossword puzzle.
Those things matter. But the Northwestern research points to something that most people dramatically underestimate.
It is not primarily about what you do for your brain. It is about how you live with other people.
Across 25 years of research and hundreds of participants, one behavioral trait consistently showed up in SuperAgers more than any other.
They were deeply social.
Not casually. Not passively scrolling through messages or attending occasional dinners. SuperAgers reported strong, active, meaningful relationships. They stayed genuinely connected to the people in their lives.
This wasn’t just an incidental observation. It appears to be central to the biology of SuperAging.
The very region of the brain that stays thickest in SuperAgers, the anterior cingulate cortex, is also the region most associated with social processing and emotional connection.
The specialized von Economo neurons that exist in unusually high numbers in SuperAger brains are thought to play a direct role in social awareness and interpersonal attunement.
The researchers aren’t suggesting that having friends is a magic cure for cognitive decline. But the convergence of brain biology and social behavior in this data is too consistent to ignore.
How This Applies to Real Life
This is where the research becomes less about science and more about choices.
Because while no one can control whether their brain produces amyloid plaques, there are factors that appear meaningfully connected to SuperAging, factors that are, at least in part, within reach.
Stay Genuinely Connected to People
According to findings across the SuperAging Program, deep social relationships remain the single most consistent lifestyle trait among SuperAgers, cutting across different exercise habits, diets, and backgrounds.
This is not about being extroverted. It is about maintaining relationships that have depth and regularity, people you can call, argue with, laugh with, and rely on.
Loneliness, by contrast, has been linked in multiple studies to faster cognitive decline and increased risk of dementia.
Keep Your Brain Challenged, Not Just Busy
SuperAgers tend to pursue mentally demanding activities, not just mentally familiar ones.
Dr. Emily Rogalski, one of the lead scientists at Northwestern, has observed that SuperAgers often engage in activities that push them slightly outside their comfort zone, learning a new language, picking up an instrument, or tackling complex problems in their work or hobbies.
Doing things your brain already knows how to do is comfortable. Growth happens at the edge of that comfort.
Emotional Resilience Matters More Than You Think
SuperAgers consistently score high on measures of psychological resilience and life satisfaction.
They tend to bounce back from setbacks more readily. They maintain a forward-looking outlook. They manage stress rather than letting it accumulate.
This is not just temperament. Chronic stress is well-documented as a contributor to memory decline, accelerating cortical thinning and disrupting the very brain structures SuperAgers work hard to preserve.
Physical Activity Helps, But Not in the Way You Expect
Here is a finding worth slowing down for.
SuperAgers don’t all exercise the same way. Their fitness routines varied widely across the research group. Some were dedicated athletes. Others were not particularly active at all.
What this suggests is that exercise supports brain health, but it is not the singular key to SuperAging that popular health culture sometimes implies.
Movement matters. But the brain appears to care at least as much, possibly more, about who you move through life with.
Why This Research Changes the Conversation on Dementia
The implications of this 25-year study reach well beyond understanding a remarkable group of outliers.
If scientists can fully map what makes SuperAger brains resistant or resilient to Alzheimer’s-related damage, they may be able to develop interventions that confer those same protections to people whose brains are currently more vulnerable.
The goal, as the researchers have framed it, is to understand not just why some brains decline, but why some don’t, and then use that knowledge to expand the second group.
This represents a meaningful shift in the research approach to dementia. Rather than only studying disease to understand how it progresses, scientists are now studying extraordinary health to understand how it persists.
That distinction matters enormously for the kinds of treatments and prevention strategies that will come next.
The Bigger Picture
There is something quietly profound in what the Northwestern SuperAgers represent.
They are not people who did everything perfectly. They are not all free of health challenges or difficult life circumstances. Some of them had Alzheimer’s proteins accumulating in their brains and simply, biologically, didn’t let it win.
What they share, across biology and behavior, is a kind of tenacity. In their brains and in their lives.
The science is still unfolding. There are no guaranteed formulas here, and researchers are careful not to overstate what can be controlled.
But the picture that emerges from 25 years of data is one worth sitting with.
The brain that stays sharp at 90 is usually not the one that was protected from everything. It is often the one that stayed engaged, stayed connected, and found ways to remain resilient in the face of what life brought.
That is less of a medical prescription and more of a philosophy. And it turns out, the two might not be so different.
References and Further Reading
- The first 25 years of the Northwestern University SuperAging Program, Alzheimer’s & Dementia, 2025
- What Makes a SuperAger? Northwestern University Feinberg School of Medicine
- These 80-year-olds have the memory of 50-year-olds. Scientists finally know why, ScienceDaily
- 4 Habits of SuperAgers, Northwestern Medicine
