Parkinson’s disease affects over 1.1 million people in the U.S. It slowly damages the brain cells responsible for controlling movement.
By the time symptoms like tremors or stiffness appear, about half of the affected brain cells are already gone. This makes early detection extremely important.
A new study published in the journal Movement Disorders offers hope for detecting the disease earlier. Scientists used brain imaging to study how Parkinson’s disease changes the way two important brain signals are linked.
The researchers used a type of brain scan called PET (positron emission tomography) to look at two key markers in the brain.
One was dopamine transporters—proteins that help move dopamine, a brain chemical that plays a key role in movement and is closely linked to Parkinson’s disease. The second was synaptic density, which measures how healthy and connected brain cells are.
In healthy people, these two markers usually increase or decrease together in a certain pattern in the striatum, the part of the brain most affected by Parkinson’s disease. But the researchers found that in people with Parkinson’s, this pattern was lost.
“Our findings suggest that Parkinson’s disease disrupts the normal link between dopamine transporter levels and synaptic density,” explained Dr. Tommaso Volpi, one of the study’s authors and a researcher at Yale School of Medicine.
Diagnosing Parkinson’s disease early is hard because its symptoms—such as tremor and muscle stiffness—can also appear in other conditions. Current imaging tests work well, but they may miss early changes in the brain. That’s why the research team wanted to explore how brain signals relate to each other, not just look at one signal alone.
The study involved 30 people with Parkinson’s disease and 13 healthy volunteers. Each person had two separate PET scans: one to measure dopamine transporters and another to measure synaptic density.
They focused on brain regions known to be affected by Parkinson’s disease and compared the results between the healthy group and those with different stages of Parkinson’s.
In healthy brains, there was a strong link between the amount of dopamine neurons and the health of their connections. But in people with Parkinson’s, that link weakened. “That’s the heart of our study,” said lead author Dr. David Matuskey, a professor at Yale.
The researchers also found that the loss of dopamine neurons was greater than the loss of synaptic density, especially in patients with more advanced Parkinson’s. This shows that as the disease gets worse, the brain changes become more obvious.
By combining different imaging techniques, scientists can get a better picture of what’s happening in the brain over time. These brain signals might become useful tools, or biomarkers, to track the disease and its progression.
Understanding how the loss of dopamine and the breakdown in brain cell connections occur—and when they occur—could explain why Parkinson’s disease worsens over time. It could also help uncover what exactly causes the disease, which scientists are still trying to fully understand.
If you care about Parkinson’s disease, please read studies that Vitamin B may slow down cognitive decline, and Mediterranean diet could help lower risk of Parkinson’s.
For more health information, please see recent studies about how wheat gluten might be influencing our brain health, and Olive oil: a daily dose for better brain health..
Copyright © 2026 Knowridge Science Report. All rights reserved.
