New research has uncovered clues as to why some people develop a rare form of dementia that is associated with language loss.

In this study, the team headed by Emily Rogalski at the Northwestern University recruited 32 patients who were diagnosed with primary progressive aphasia (PPA) and examined the amount of amyloid buildup in their brains using Amyloid Positron Emission Tomography (PET) Imaging. Amyloid, a toxic protein, has been tied to Alzhemier's disease, the leading cause of dementia. Nineteen participants had high accumulations of amyloid and were considered very likely to be diagnosed with Alzheimer's. Twenty-two additional people who were diagnosed with Alzheimer's were used for comparison.

The team found that participants with PPA tended to have more amyloid buildup on the left side of the brain, which is associated with language, as opposed to the right. This finding suggests that researchers can potentially track the development of PPA and other forms of dementia by analyzing and comparing the amount of amyloid buildup.

"By understanding where these proteins accumulate first and over time, we can better understand the course of the disease and where to target treatment," said Rogalski, a research associate professor at Northwestern's Cognitive Neurology and Alzheimer's Disease Center (CNADC).

The study's first author, Adam Martersteck, a graduate student in Northwestern's neuroscience program, added that the use of Amyloid PET Imaging "is very exciting for Alzheimer's research."

"Not only can we tell if a person is likely or unlikely to have Alzheimer's disease causing their PPA, but we can see where it is in the brain," Martersteck said. "By understanding what the brain looks like in the beginning stages of Alzheimer's, we hope to be able to diagnose people earlier and with better accuracy."

This is the first study to use this imaging technique to compare how amyloid is distributed in the brains of PPA and Alzheimer's patients. The researchers hope that this technique can be used to advance diagnostic techniques and treatments for different types of dementia.

Not much is known about the development of Alzheimer's and PPA. Prior to this study, researchers had examined amyloid buildup post-mortem when the toxic protein had already taken over the entire brain.

The study's findings were published in the journal Annals of Neurology.