A new study led by researchers at Vanderbilt Health has identified medical conditions that often precede an Alzheimer’s disease diagnosis. The findings, published in the journal Alzheimer’s Research & Therapy, could open opportunities to develop interventions that reduce Alzheimer’s disease risk.

Social memory—the ability to recognize familiar individuals and distinguish them from strangers—is fundamental to social cognition. Deficits in social memory are hallmarks of multiple neuropsychiatric and neurodegenerative disorders, including autism spectrum disorder (ASD), post-traumatic stress disorder (PTSD), and Alzheimer's disease (AD). Notably, these conditions frequently co-occur with chronic sleep disturbances. Although extensive evidence linking sleep disruption to impaired social cognition, the underlying circuit-level and neurochemical mechanisms have remained largely unresolved. To address these challenges, the research team led by Prof. Haibo Xu and Prof. Linlin Bi at Wuhan University employed a combination of high-resolution oxytocin (OXT) sensor imaging, optogenetics, calcium imaging, and electrophysiological approaches to uncover the neural circuit mechanisms underlying sleep disruption–induced social memory impairment, as well as potential intervention strategies.

A research team in Kumamoto University has discovered that a natural compound found in pomegranate leaves and branches can directly break down harmful protein aggregates linked to transthyretin (TTR) amyloidosis, a progressive and potentially life-threatening disease affecting the nerves and heart.

Subtle changes in how blood flows through the brain and how brain tissue uses oxygen may be closely linked to Alzheimer’s disease risk, according to new research from the Mark and Mary Stevens Neuroimaging and Informatics Institute (Stevens INI) at the Keck School of Medicine of USC. Stevens INI researchers found that noninvasive measures of brain blood flow and oxygenation were associated with hallmark brain changes in older adults with and without cognitive impairment, including amyloid buildup and a smaller hippocampus, a region essential for memory. The findings suggest that vascular health of the brain may play an important role early in the disease process and could help identify individuals at risk before significant symptoms appear. The research team used two noninvasive tools that can be applied while a person rests quietly. Transcranial Doppler ultrasound measures how fast blood moves through major brain arteries, while near-infrared spectroscopy measures how well oxygen reaches brain tissue near the surface of the cortex. Advanced mathematical models were then used to summarize these signals into indicators that reflect how well the brain adjusts blood flow and oxygen delivery in response to natural changes in blood pressure and carbon dioxide levels. Higher values on these indicators, meaning brain blood vessels behaved more like those of cognitively healthy adults, were linked to lower levels of amyloid plaques and larger hippocampal volume. Both of these brain features are associated with a lower risk of Alzheimer’s disease.