Neurons use simple physics to maintain their connections, but these processes change in Alzheimer’s patients

Scientists at Auburn University have uncovered a fundamental principle of how brain cells stay connected, and their discovery could change how we understand Alzheimer’s disease. Published in Cell Reports, this study reveals that neurons—the cells that make up our brain—use simple physics to maintain their connections, and that these processes change in Alzheimer’s patients.

For decades, scientists have wondered how brain cells keep in touch with each other even when they’re not actively sending signals. Dr. Michael W. Gramlich and his team at Auburn University have now provided an answer, using physics to explain this process for the first time.

“We’ve found that neurons use a type of natural force based on entropy—like an invisible glue—to keep their connections strong,” said Dr. Gramlich. “And when this process stops working correctly, it may be an early sign of Alzheimer’s disease.”

Imagine a city where all the traffic lights are always working, keeping cars moving efficiently. Now imagine what happens when some of those lights malfunction—cars pile up, traffic slows, and chaos ensues. This is similar to what happens in the brain when neurons fail to maintain their connections during the early stages of AD. In a healthy brain, neurons stay connected using specific molecular rules even when they’re at rest. But in Alzheimer’s disease, these connections start breaking down, leading to memory loss and cognitive decline.

Dr. Gramlich’s team discovered that neurons maintain a specific density of objects, called vesicles, to preserve these crucial connections. Using advanced microscopes and computer models, they found that the denser these vesicles are, the stronger the connection between neurons. The results also suggest that neurons use vesicle density as a way to increase or decrease the connections as well.

A breakthrough in understanding Alzheimer’s disease

One of the most exciting findings of this study is that changes in these neuronal connections could be an early warning sign of Alzheimer’s disease. The research team found that in brains affected by Alzheimer’s disease, the density of vesicles is significantly altered, disrupting the brain’s ability to communicate. While past research teams have focused on the biological basis of Alzheimer’s disease, this study shows that using fundamental physics in combination with biology can provide a new path forward toward solving the problem of Alzheimer’s disease.

“This discovery gives us a new way to think about Alzheimer’s disease,” said Dr. Gramlich. “If we can find ways to restore these connections, we might be able to slow down or even prevent some of the damage caused by the disease.”

This study was the result of a collaborative effort at Auburn University, with contributions from Dr. Miranda Reed and graduate student Paxton Wilson, along with three undergraduate students. Their work not only advances our understanding of brain function but also opens the door for new treatments that could help millions of people worldwide.

The findings of this research could have far-reaching implications, potentially influencing future treatments for neurodegenerative diseases. By uncovering how neurons maintain their connections, scientists now have a new target for therapies aimed at keeping the brain healthy as we age. This work builds upon the collaboration’s previous successful studies on the underlying molecular and physical processes that lead to Alzheimer’s disease and dementia.