Researchers report that certain movement-related symptoms of Alzheimer’s disease may originate in the peripheral nervous system rather than the brain.
Researchers at the University of Central Florida say some early movement problems linked to Alzheimer’s may begin outside the brain, raising new questions about where the disease starts and how soon it might be detected. If confirmed in further studies, the finding could help explain why subtle changes in walking, balance, or muscle control sometimes appear before memory loss becomes obvious.
The study was led by UCF Nanoscience Technology Center Professor James Hickman and Research Professor Xiufang “Nadine” Guo. Working with scientists from healthcare technology company Hesperos, the team used lab-grown human cell systems that mimic how the body functions to examine how genetic mutations tied to familial Alzheimer’s affect movement.
The findings were recently published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
“Motor deficits may be an earlier indication [of Alzheimer’s],” she says. “If we can detect those changes and intervene earlier, that could help delay the onset of central nervous system symptoms.”
How Movement and Alzheimer’s Are Connected
Familial Alzheimer’s is a rare inherited form of the disease that develops earlier (from 40 to 65 years of age) than the more common type.
Although Alzheimer’s is best known for memory loss and dementia, doctors have long reported that some patients experience changes in balance, gait (manner of walking), or movement years before cognitive symptoms appear. These early signs suggest that aspects of the disease may start outside the brain.
Using an advanced laboratory approach, the researchers showed that affected motor neurons can disrupt the neuromuscular junction, a key connection required for movement, even without input from the brain.
“This is the first time it’s been demonstrated that deficits in the peripheral nervous system can arise directly from these mutations,” Hickman says. “It means drugs that target the brain may not fix problems in the rest of the body.”
