Task-evoked dorsal attention network activity and AD pathology influence memory formation in cognitively unimpaired older adults.
Category: neuroscience
Detailed imaging of key receptors suggests new avenue for repairing brain function
For the first time, scientists using cryo-electron microscopy have discovered the structure and shape of key receptors connecting neurons in the brain’s cerebellum, which is located behind the brainstem and plays a critical role in functions such as coordinating movement, balance and cognition.
The research, published in Nature, provides new insight that could lead to the development of therapies to repair these structures when they are disrupted either by injury or genetic mutations affecting motor skills —sitting, standing, walking, running, and jumping—learning and memory.
The study, by scientists at Oregon Health & Science University, reveals the organization of a specific type of glutamate receptor—a chemical neurotransmitter that conveys signals between neurons and is considered the primary excitatory neurotransmitter in the brain—bound together with proteins clustered on synapses, or junctions, between neurons in the cerebellum.
Simple insulin resistance test may also predict cognitive decline in Alzheimer’s patients
Insulin resistance detected by routine triglyceride-glucose (TyG) index can flag people with early Alzheimer’s who are four times more likely to present rapid cognitive decline, according to new research presented at the European Academy of Neurology (EAN) Congress 2025.
Neurologists at the University of Brescia reviewed records of 315 non-diabetic patients with cognitive deficits, including 200 with biologically confirmed Alzheimer’s disease. All subjects underwent an assessment of insulin resistance using the TyG index and a clinical follow-up of three years.
The work is published in the journal Alzheimer’s & Dementia.
Earwax Biomarkers for Early Parkinson’s Disease Detection
Most treatments for Parkinson’s disease (PD) only slow disease progression. Early intervention for the neurological disease that worsens over time is therefore critical to optimize care, but that requires early diagnosis. Current tests, like clinical rating scales and neural imaging, can be subjective and costly. Now, researchers in ACS’ Analytical Chemistry report the initial development of a system that inexpensively screens for PD from the odors in a person’s earwax.
Previous research has shown that changes in sebum, an oily substance secreted by the skin, could help identify people with PD. Specifically, sebum from people with PD may have a characteristic smell because volatile organic compounds (VOCs) released by sebum are altered by disease progression — including neurodegeneration, systemic inflammation and oxidative stress.
However, when sebum on the skin is exposed to environmental factors like air pollution and humidity, its composition can be altered, making it an unreliable testing medium. But the skin inside the ear canal is kept away from the elements. So, Hao Dong, Danhua Zhu and colleagues wanted to focus their PD screening efforts on earwax, which mostly consists of sebum and is easily sampled.
Alzheimer’s: Bacteria that cause stomach ulcers may also protect brain
Every three seconds, someone in the world develops dementia. Alzheimer’s disease is the most common form of dementia, accounting for between 60% and 70% of all cases.
Although scientists have made significant progress in understanding the disease, there’s still no cure. That’s partly because Alzheimer’s disease has multiple causes—many of which are still not fully understood.
Two proteins which are widely believed to play central roles in Alzheimer’s disease are amyloid-beta and tau. Amyloid-beta forms sticky plaques on the outside of brain cells. This disrupts communication between neurons. Tau accumulates inside brain cells, where it twists into tangles. This ultimately leads to cell death. These plaques and tangles are the hallmark features of Alzheimer’s disease.
Scientists find cellular brain changes tied to PTSD
The human brain is made up of billions of interconnected cells that are constantly talking to each other. A new study published in Nature zooms in to the single-cell level to see how this cellular communication may be going wrong in brains affected by post-traumatic stress disorder (PTSD).
Until recently, researchers did not have the technology to study genetic variation within individual cells. But now that it’s available, a team led by Matthew Girgenti, Ph.D., assistant professor of psychiatry at Yale School of Medicine, has been analyzing brain cells to uncover genetic variants that might be associated with psychiatric diseases such as major depressive disorder (MDD) and PTSD.
Their latest study is one of the first to examine a major psychiatric disorder, PTSD, at the single-cell level. For years, doctors have been prescribing antidepressants to treat the condition because there are currently no drugs specifically designed for PTSD. Girgenti hopes that identifying novel molecular signatures associated with the psychiatric disease can help researchers learn how to develop new drugs or repurpose existing ones to treat it more effectively.