Lead: A study published in Nature on 25 February 2026 finds that so-called “SuperAgers” — people aged 80 and older with exceptional memory — produce roughly twice the number of immature neurons as cognitively healthy older adults and about 2.5 times as many as people with Alzheimer’s disease. Researchers at Northwestern University and the University of Illinois at Chicago used multiomic single-cell sequencing and postmortem tissue to compare five donor groups, identifying a hippocampal environment that supports ongoing neuron birth and integration. Coauthors, including Dr. Tamar Gefen and Orly Lazarov, say the results indicate an aging brain can remain capable of regenerating cells that support memory.
- SuperAgers (age 80+) had ~2x more young neurons than cognitively healthy older adults and ~2.5x more than donors with Alzheimer’s disease, per the Nature study.
- SuperAgers’ hippocampi showed a cellular milieu—astrocytes plus CA1 neuron signaling—that appears to nurture neurogenesis and synaptic integration.
- Brains from SuperAgers contained more newly formed neurons than adults in their 30s–40s, according to the authors’ measurements.
- The cingulate cortex was thicker in SuperAgers versus typical middle‑aged adults, linked to attention and engagement measures.
- Hippocampal tissue from SuperAgers had about three times fewer tau tangles, a hallmark of Alzheimer’s pathology.
- Some SuperAgers have common vascular or metabolic conditions, indicating diverse health profiles among this group.
- Multiomic single-cell sequencing identified astrocytes and CA1 neurons as key cellular drivers of preserved memory in SuperAgers.
Background
“SuperAgers” is a research-defined cohort of adults aged 80 and older whose episodic memory performance matches or exceeds people decades younger; the Northwestern SuperAging Program has followed such volunteers for about 25 years. The concept responds to longstanding questions about human brain aging: why some individuals retain sharp cognition while others develop progressive decline. Past human studies of adult neurogenesis reached mixed conclusions, partly because of differences in tissue handling and measurement techniques. This new work applies multiomic single-cell sequencing to postmortem hippocampal samples across five donor groups to map which cell types and molecular states correlate with preserved memory.
The investigators compared SuperAgers to younger adults (30s–40s), older adults without decline, people with early dementia, and those with clinically diagnosed Alzheimer’s disease. By preserving the identities of individual cell types and their gene-expression profiles, the team aimed to detect not just neurons but the supporting cellular ecosystem—astrocytes, interneurons and synaptic partners—that together enable plasticity. Lead and senior authors emphasize they are measuring markers of immature neurons and regulatory circuits that promote survival and integration, not just static cell counts. That distinction addresses earlier debates about whether neurogenesis meaningfully persists into late life.
Main Event
Using multiomic single-cell sequencing and histological validation, researchers quantified newborn neuron markers and mapped supporting cell types in the hippocampus. Tissue from SuperAgers showed elevated markers of immature neurons plus transcriptional signatures indicating higher synaptic readiness and excitability. The team also observed structural differences: entorhinal cortex neurons in some SuperAgers were larger and displayed features of greater integrity than neurons in much younger donors. Together these observations suggest both ongoing neuron birth and a scaffold that helps those cells connect into existing circuits.
Coauthor Dr. Tamar Gefen described SuperAgers’ immature neurons as more excitable and capable of integrating into hippocampal networks, while Orly Lazarov highlighted the resilience of the neurogenic profile. The analysis pointed to two cell types—astrocytes and CA1 pyramidal neurons—as coordinating partners: astrocytes regulate blood flow and synapse formation, and CA1 cells are central to consolidating and retrieving episodic memories. Compared with donors who had Alzheimer’s pathology, SuperAger tissue showed fewer tau tangles in the hippocampus and gene-expression patterns consistent with synaptic maintenance.
Methodologically, the study combined single-cell molecular maps with conventional histology to cross-validate immature‑neuron counts and marker expression. Donor groups included multiple brain-banked specimens per category, enabling statistical comparisons across ages and diagnostic groups. The authors caution that postmortem studies capture a late snapshot and cannot by themselves prove causation, but the converging molecular and structural signals strengthen the interpretation that a youthful, supportive niche underlies SuperAgers’ preserved cognition.
Analysis & Implications
The finding that some older adults maintain active neurogenesis and an enriched hippocampal environment reframes how we think about cognitive aging: plasticity may persist in late life under certain biological conditions. If neurogenic capacity and a nurturing cellular ecosystem explain preserved memory, interventions that enhance those features—whether pharmacologic, lifestyle, or vascular risk management—could become targets to slow or prevent decline. However, researchers stress that SuperAgers represent a heterogeneous set: some had medical comorbidities, so biology, behavior and chance may all contribute.
Genetics likely plays a role in predisposing some individuals to retain neurogenic niches, but causal pathways remain to be defined. Independent experts quoted in the report note that lifestyle changes (exercise, diet, sleep optimization, stress reduction, and vascular risk control) have been linked in other studies to hippocampal growth and reduced Alzheimer’s markers, suggesting modifiable factors can influence brain structure and function. Translating the molecular signatures of SuperAgers into practical therapies will require longitudinal clinical work and trials that test whether boosting the supportive niche actually increases neuron survival and improves cognition.
At a population level, the study raises questions about resilience to neurodegeneration: if specific cell types like astrocytes and CA1 neurons are pivotal, biomarker development could focus on their states to identify people likely to benefit from targeted prevention. Internationally, the findings may prompt reexamination of aging cohorts across diverse genetic and environmental backgrounds to see whether the SuperAger profile is universal or population-specific. Finally, the work underscores the importance of multiomic, cell-resolved approaches for revealing mechanisms that bulk tissue studies can miss.
Comparison & Data
| Donor group | Relative young‑neuron count | Hippocampal tau burden (relative) |
|---|---|---|
| SuperAgers (80+) | Baseline ×1.0 (reference) | ~1× (lowest; ~3× fewer vs typical Alzheimer’s samples) |
| Cognitively healthy older adults | ~0.5× (about half the SuperAger level) | Higher than SuperAgers |
| Alzheimer’s disease | ~0.4× (≈2.5× fewer than SuperAgers) | Highest tau burden |
| Young adults (30s–40s) | Lower than SuperAgers by the study’s measures | Lower tau than typical old-age Alzheimer’s samples |
The table condenses reported relationships: SuperAgers had the highest relative markers of immature neurons and a lower tau signal in hippocampal tissue than donors with Alzheimer’s pathology. Authors used both molecular markers and histology to ensure that the observed differences reflect cellular state and structure rather than artifacts of sampling or measurement. Readers should note the study reports relative comparisons across groups rather than absolute per‑brain counts available for clinical use.
Reactions & Quotes
“This shows the aging brain retains regenerative capacity,”
Dr. Tamar Gefen, Northwestern University (study coauthor)
Gefen framed the result as evidence that immature neurons in SuperAgers are unusually ready to form functional connections, describing them as more excitable and more likely to integrate into memory circuits.
“The neurogenic profile we observe suggests resilience to time,”
Orly Lazarov, University of Illinois Chicago (senior author)
Lazarov emphasized the combination of molecular and structural findings that together point to preserved plasticity rather than a single protective factor.
“Lifestyle measures can grow hippocampal regions and reduce Alzheimer’s markers,”
Dr. Richard Isaacson, Institute for Neurodegenerative Diseases (external expert)
Isaacson, not involved in the study, noted that prior intervention studies link exercise, diet, sleep and vascular risk control to structural brain improvements—caveating that direct replication of the SuperAger profile by lifestyle change alone remains to be proven.
Unconfirmed
- Whether the SuperAger neurogenic and structural profile is primarily genetic, environmental, or a combination remains unresolved and not established as causal.
- It is unconfirmed if lifestyle interventions in midlife or later can reproduce the full SuperAger cellular ecosystem in typical older adults.
- The extent to which the study’s postmortem snapshot reflects lifelong trajectories versus late-life changes is not yet determined.
Bottom Line
The Nature study provides compelling cell‑level evidence that some people in their 80s and 90s maintain a hippocampal environment conducive to forming and integrating new neurons, and that this environment correlates with preserved episodic memory and lower tau pathology. While the findings do not prove a single cause, they identify astrocytes and CA1 circuits as promising targets for biomarker development and future interventions aimed at preserving cognition.
For clinicians and the public, the results reinforce a dual message: biological resilience can persist into advanced age, and modifiable factors—exercise, sleep, stress reduction and vascular risk management—remain sensible parts of a prevention strategy. Translating these molecular insights into treatments will require longitudinal studies and clinical trials to test whether boosting the supportive niche actually increases neuron survival and cognitive resilience.
Sources
- CNN — news report summarizing the Nature study and interviews with investigators (media).