The Brain's Secret Against Aging

Among seniors aged 80 and above, 'SuperAgers' who maintain exceptional memory capabilities generate new neurons at a rate more active than not only average elderly individuals but also young adults, according to a new study. Published in the international journal Nature on February 24 by a joint research team from the University of Illinois Chicago (UIC), Northwestern University, and Washington University, this study provides the first evidence that the neural regeneration capacity of adult brains varies dramatically between individuals.

The research team analyzed donated brain tissue from five groups: healthy young adults, average elderly individuals, SuperAgers, patients with mild dementia, and Alzheimer's disease patients. Results showed that neurogenesis in the hippocampus (the memory center) of SuperAgers occurred at approximately twice the rate of average elderly individuals. In contrast, almost no new neuron generation was observed in the brains of Alzheimer's patients.

Brain Cells 'Remember' Their Fetal Origins

A separate study from the Karolinska Institute, published in Nature Neuroscience on March 18, provides clues to the mechanism behind this phenomenon. When the research team mapped epigenetic regulatory processes across the adult human brain and spinal cord, they discovered that brain cells, including oligodendrocytes, maintain genetic markers from developmental stages even decades later.

Epigenetics is the field that studies how gene expression is regulated without changes to the DNA sequence. This discovery suggests that adult brain cells retain a 'genetic blueprint' formed during fetal and infant stages as a form of memory, which serves as a key mechanism for maintaining neural identity throughout life.

Professor Orly Lazarov of UIC Medical School stated, "This research represents major progress in understanding how the human brain processes cognition, forms memories, and ages. Identifying why some brains age more healthily than others will help develop treatments for healthy aging, cognitive resilience, and dementia prevention."

From '20th Century Impossibility' to 21st Century Treatment Potential

The possibility of neuron regeneration in adult brains has long been a subject of debate. Until the late 20th century, the neuroscience community accepted the conventional wisdom that "new neurons are not generated in adult brains." However, the paradigm began to shift in the late 1990s when neurogenesis was observed in the hippocampal region of rodents.

Subsequent primate studies revealed that neurogenesis is linked to memory formation and processing capabilities, but in humans, direct evidence was difficult to obtain due to the limitation of analyzing only donated brain tissue. This study is significant in that it quantitatively demonstrated neurogenesis in adult humans for the first time using brain tissue samples secured through Northwestern University's SuperAger program.

Future Prospects [AI Analysis]

This discovery provides important implications in two directions. First, the fact that adult brains maintain hidden regenerative potential likely presents new approaches to dementia drug development. In particular, if the mechanisms of high-level neurogenesis observed in SuperAger brains can be identified, it could lead to the development of treatments applicable to average elderly individuals.

Second, as researchers pointed out, there is also a possibility that epigenetic memory may increase vulnerability to brain tumors. This is because cells that maintain developmental-stage genetic markers could increase tumor risk if abnormally activated. Therefore, future research is expected to proceed in directions that promote neurogenesis while ensuring safety.

The Karolinska Institute and UIC research teams have currently begun developing treatments targeting epigenetic regulatory mechanisms. If their research succeeds, clinical treatments that suppress age-related cognitive decline may emerge by the mid-2030s.