The Science of Super-Agers: Secrets to Brain Health and Longevity

New research into the brains of individuals known as super-agers has identified a significant biological difference in how their brains maintain cognitive function into old age. These individuals, defined as adults aged 80 and older who possess the memory capacity of someone at least two to three decades younger, demonstrate a unique ability to generate new neurons.

A study conducted by scientists at the University of Illinois College of Medicine Chicago, published in the journal Nature, found that super-agers generate twice as many new neurons in the hippocampus as typical older adults. The hippocampus is the region of the brain critical for learning and memory.

The Role of Neurogenesis and Plasticity

The discovery centers on neurogenesis, which is the birth and survival of new neurons. This process enhances brain plasticity, allowing the brain to repair itself and maintain cognitive function despite the natural process of aging or potential injury.

According to Dr. Tamar Gefen, an associate professor of psychiatry and behavioral sciences at the Mesulam Institute for Cognitive Neurology and Alzheimer’s Disease at Northwestern University Feinberg School of Medicine, young neurons are the most adaptable and plastic type of brain cells. They possess an enhanced ability to grow, integrate, and wire themselves into the brain.

The research indicates that super-agers maintain a higher number of these immature neurons, which are characterized by heightened excitability. This cellular environment allows for higher cognitive performance and makes the super-ager brain more accommodating.

This discovery means that the super-agers have a molecular capability that allows them to have higher [cognitive] performance, and that includes more neurogenesis.

Orly Lazarov, director of UIC’s Alzheimer’s Disease and Related Dementia Training Program

Biological Support Systems

Beyond the production of neurons, the study found that super-ager brains contain more robust support systems within the hippocampus. These systems nurture youthful neurons, creating a cellular environment that supports ongoing neurogenesis.

The research compared 38 brains across five distinct groups: healthy adults aged 40 and younger, healthy older adults, people in early stages of cognitive decline, people diagnosed with Alzheimer’s disease, and super-agers. The findings revealed that super-agers produce twice the number of young neurons as cognitively healthy older adults and 2.5 times as many as those with Alzheimer’s disease.

Defining the Super-Ager

The term super-ager was coined by Dr. M. Marsel Mesulam, founder of the Mesulam Institute for Cognitive Neurology and Alzheimer’s Disease at the Northwestern University Feinberg School of Medicine. These individuals are identified through delayed word recall testing to determine if their memory capacity matches that of someone significantly younger.

Experts from Harvard Medical School and Beth Israel Deaconess Medical Center note that while super-agers are physically similar to their peers, they differ significantly in brain volume in areas linked to memory and typically do not develop dementia.

Dr. Andrew Budson, a lecturer in neurology at Harvard Medical School, suggests that super-aging is partly the result of consistent behaviors and lifestyle choices that promote optimal brain health, though the recent University of Illinois research also highlights a genetic advantage.

Implications for Brain Health

While the molecular and genetic advantages of super-agers are distinct, research suggests that practicing good brain health may help other individuals prevent cognitive decline. The ability of the aging brain to regenerate neurons suggests a level of plasticity that was previously less understood.

The study of super-agers has been a focus of the Northwestern SuperAging Program for 25 years, seeking to understand why some individuals retain a special spark and quick-wittedness well into their 80s and 90s.