Over-80s with the memory of a 50-year-old: The secrets of super-agers from 25 years of research

(Adnkronos) – They are over 80 years old and possess exceptional memory skills that put them on par with people 30 years younger. They are truly social animals: they shun loneliness and enjoy cultivating human relationships. Their brains seem to have a sort of "shield" that makes them immune to decline and the ravages of time. Scientists call them "Super Agers" and have compiled their profile over 25 years of studies. These super-elderly individuals possess a super-brain that could offer valuable clues in the century's battle against dementia and neurodegenerative diseases like Alzheimer's. A team from Northwestern University in Chicago, pioneers in this field of research, is uncovering the secrets of "perennial" minds.

Super Agers, experts explain, are unique because they challenge the entrenched belief that cognitive decline is an inevitable part of aging. And over a quarter-century of studies, scientists have noted some unique characteristics, notable lifestyle and personality differences between Super Agers and normal aging individuals, such as sociability and the ability to be social. But "it's what we discovered in their brains that was really shocking to us," says Sandra Weintraub, professor of psychiatry, behavioral sciences, and neurology at Northwestern University Feinberg School of Medicine. By identifying the biological and behavioral traits associated with Super Aging, scientists hope to discover new strategies to promote cognitive resilience and delay or prevent Alzheimer's and other diseases that cause cognitive decline and dementia.

"Our findings demonstrate that exceptional memory in old age is not only possible, but is also linked to a specific neurobiological profile. This opens the door to new interventions aimed at preserving brain health even in the final decades of life," confirms Weintraub, corresponding author of a new article summarizing the findings, published in Alzheimer's & Dementia (a journal of the Alzheimer's Association) as part of the journal's special issue celebrating the 40th anniversary of the National Institute on Aging's Alzheimer's Disease Centers program and the 25th anniversary of the National Alzheimer's Coordinating Center.

Being resilient and resistant. The term 'Super Ager' was coined by expert M. Marsel Mesulam, founder of the Mesulam Center for Cognitive Neurology and Alzheimer's Disease at Northwestern University, in the late 1990s. Since 2000, a cohort of 290 Super Ager participants has passed through the center's doors, and scientists have performed autopsies on 77 Super Ager brains donated for research. Some contained amyloid and tau proteins (plaques and tangles), known to play a key role in the progression of Alzheimer's, while others had not developed any. "We realized that there are two mechanisms that lead someone to become a Super Ager," Weintraub explains. "One is resistance: plaques and tangles don't form. The second is resilience: they form, but the brain doesn't change."

As evidence of their exceptional memory performance, Super Agers have been shown to score at least 9 out of 15 on a delayed word recall test, on par with people in their 50s and 60s. And they have a "youthful" brain structure: unlike brains that typically age, they show no significant thinning of the cortex—the outer layer of the brain—and even have a thicker anterior cingulate cortex than younger adults. This crucial brain region plays a significant role in integrating information related to decision-making, emotions, and motivation.

Another factor is their unique cellular characteristics: compared to their normally aging peers, Super Agers have more Ven (von Economo) neurons, which are specialized cells linked to social behavior, and larger entorhinal neurons, which are crucial for memory. Finally, despite different lifestyles and approaches to exercise, Super Agers all tend to be very sociable and report strong interpersonal relationships. The Mesulam center evaluates these super-elderly individuals annually, who can then decide to donate their brains to science for postmortem evaluation by Northwestern scientists. "Many of the findings in this paper," says co-author Tamar Gefen, associate professor of psychiatry and behavioral sciences at Feinberg, "arise precisely by examining brain samples from generous and dedicated Super Agers, followed for decades. I am constantly amazed by how brain donation can enable the discovery of new horizons long after death, offering a kind of scientific immortality."