Many older adults experience cognitive decline due to protein buildup and neuron loss. But some, known as super-agers, maintain mental sharpness into their 80s.
A study published in Nature finds super-agers-those 80 and older with memories akin to people decades younger-have roughly twice as many new neurons in the hippocampus compared to peers with normal aging, and 2.5 times more than those with Alzheimer’s.
Researchers identified neural stem cells, neuroblasts, and immature neurons in autopsied brains across four groups: super-agers, cognitively normal older adults, those with mild impairment, and Alzheimer’s patients.
The super-agers not only had higher counts of immature neurons but also unique genetic and epigenetic profiles that may protect them from aging.
Alzheimer’s patients showed a paradoxical increase in neural stem cells but drastically fewer mature cell types-suggesting a block in neurogenesis progression.
Experts say this could open new therapeutic routes: reactivating dormant stem cells might slow or reverse cognitive decline.
While debate continues over whether adult humans generate new neurons, this study offers compelling biological evidence of brain plasticity well into old age.