Chanda Simfukwe, Seong Soo A. An, Young Chul Youn
Mechanisms and Impact of Cognitive Reserve in Normal Aging and Alzheimer’s Disease
Diagnostics 15(23):3068 (2025)
Aging-related disease
We study how the brain changes with age and why some older adults are more likely to develop dementia, through brain-age prediction, cognitive reserve and later-life risk factors.
Age is the biggest risk factor for Alzheimer's disease and most other neurodegenerative diseases, but people age at very different rates. Part of our work asks how to measure this. We have trained machine learning models to estimate "brain age" from brain MRI of healthy adults in an East Asian community, and from Rey–Osterrieth Complex Figure drawings by nearly 2,000 healthy Korean adults. A brain that looks older than its owner may be an early sign of dementia. In 174 adults aged 60 to 85, we compared resting-state qEEG measures with plasma amyloid-β oligomer levels. A review of cognitive reserve looks at how education, complex work, bilingualism and mentally active lives help some people keep their thinking skills despite Alzheimer's-related changes in the brain.
We also review what raises or lowers dementia risk in later life. Older adults often take several medicines at once, so we examined whether common drugs such as painkillers, anticholinergics, benzodiazepines, proton pump inhibitors and statins affect dementia risk; the evidence is still mixed. Other reviews cover the gut–brain axis and the gut microbiome, vitamin D (calcitriol) and its receptor genes, chronic stress and the hypothalamic–pituitary–adrenal (HPA) axis, and garden herbicides such as paraquat and glyphosate.
Key methods
- Machine learning brain-age prediction from MRI and neuropsychological drawings
- Resting-state qEEG compared with plasma amyloid-β oligomers in older adults
- Reviews of cognitive reserve and how it is measured
- Reviews of later-life risk factors: medicines, gut microbiome, vitamin D, stress and environmental chemicals
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Medication Exposure and Risk of Dementia and Alzheimer’s Disease
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Role of Calcitriol and Vitamin D Receptor (VDR) Gene Polymorphisms in Alzheimer’s Disease
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Postoperative cognitive changes after total knee arthroplasty under regional anesthesia
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THE ROLE OF DENDRITIC BDNF TRANSCRIPTS ON ALTERED INHIBITORY CIRCUITRY IN AGING AND DEPRESSION
D-Scholarship@Pitt (University of Pittsburgh) (2015)
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Molecular and Genetic Characterization of Depression: Overlap with Other Psychiatric Disorders and Aging
Complex Psychiatry 1(1):1–12 (2015)
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DNA Methylation as a Mechanism for Age-Related Changes in Gene Expression in the Human Orbital Frontal Cortex
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