For more than 25 years, researchers at Northwestern Medicine have been studying people over 80, known as “superagers,” to understand how some people maintain extraordinary mental sharpness late in life.
These people consistently perform on memory tests at levels similar to those at least 30 years younger, challenging the long-held belief that age-related cognitive decline is inevitable.
Through decades of research, scientists have noticed several lifestyle and personality traits that distinguish superagers from other people, including being highly outgoing and sociable. Still, the most surprising discoveries came from examining their brains. “What we found in their brains was very shocking to us,” said Dr. Sandra Weintraub, professor of psychiatry, behavioral sciences, and neurology at Northwestern University Feinberg School of Medicine.
By identifying both the biological and behavioral patterns associated with hyperaging, researchers hope to develop new approaches to enhance cognitive resilience and reduce the risk of Alzheimer’s disease and other dementias.
“Our findings show that exceptional memory in old age is not only possible, but is associated with a unique neurobiological profile. This opens the door to new interventions aimed at maintaining brain health in the later decades of life,” said Weintraub, corresponding author of a new paper summarizing the results.
The survey results were published as a perspective article. Alzheimer’s Disease and Dementia: Journal of the Alzheimer’s Associationpart of a special issue commemorating the 40th anniversary of the National Institute on Aging’s Alzheimer’s Disease Center Program and the 25th anniversary of the National Alzheimer’s Coordinating Center.
A resilient and resilient brain
The “SuperAger” label was introduced by Dr. M. Marcel Meslam, who founded the Meslam Center for Cognitive Neurology and Alzheimer’s Disease at Northwestern in the late 1990s.
Since 2000, 290 participants have participated in the program, and researchers have studied the postmortem brains of 77 donated superagers. Some of these brains showed the presence of amyloid and tau proteins (also known as plaques and tangles), which are strongly associated with Alzheimer’s disease. Others showed no signs of these harmful proteins.
“What we realized is that there are two mechanisms that lead people to become superagers,” Weintraub said. “One is resistance. They don’t create plaques and tangles. The second is resilience. They create them, but they don’t do anything to the brain.”
Important discoveries about superagers
Researchers have uncovered several characteristics that help explain why superagers maintain such strong cognitive abilities.
- Outstanding memory performance: Superagers score over 9 out of 15 on delayed word recall tests, comparable to the performance of people in their 50s and 60s.
- Youthful brain structure: Unlike a typical aging brain, there is little thinning of the cortex, the outer layer of the brain. In some cases, an area called the anterior cingulate cortex is even thicker than in young adults, supporting decision-making, emotion, and motivation.
- Unique cellular features: Very old people have larger numbers of von Economo neurons associated with social behavior, along with larger entorhinal neurons that play an important role in memory.
- Strong social connections: Although exercise habits and lifestyles vary, most superagers are highly social and maintain close relationships.
Brain donation and long-term discovery
At the Meshulam Center, participants are evaluated annually and can choose whether to donate their brains for postmortem scientific research. These donations have been essential to many of the program’s most important discoveries.
“Many of the findings in this paper come from examining brain specimens from generous and devoted super-agers who were followed for decades,” said co-author Dr. Tamar Geffen. He is an associate professor of psychiatry and behavioral sciences at Feinberg College, director of Feinberg’s Institute for Translational Neuropsychology, and a neuropsychologist at the Meshulam Center. “I’m always amazed at how brain donation allows discoveries to be made long after death, providing a kind of scientific immortality.”
Groundbreaking research on super-aging
This research is detailed in a Perspective article titled “The First 25 Years of the Northwestern Super Aging Program.” Additional contributors include Dr. Meslam and Changiz Geula, research professor of cell and developmental biology and neuroscience at Feinberg College and member of the Meslam Center.
Researchers hope these findings will help guide future strategies to protect brain health and help more people maintain sharp thinking into old age.
Important points
- Superagers are people over the age of 80 who have amazingly good memories and perform at least as well as people 30 years younger.
- They tend to be highly social and mentally engaged, and their brains exhibit an ability to resist the buildup of plaques and fibrous changes associated with Alzheimer’s disease.
- Scientists believe these insights could transform brain health research and lead to new ways to slow or prevent dementia associated with diseases such as Alzheimer’s disease and frontotemporal degeneration.
