A groundbreaking new study finds that a toxic buildup of a certain type of protein in the brain may result in a rare form of dementia that results in language loss.

Using high-tech imaging, scientists at Northwestern University were able to find that a buildup of amyloid protein in the brain’s language centers resulted in a type of language-loss dementia called primary progressive aphasia (PPA), according to a university statement.

They compared this buildup with memory loss related to Alzheimer’s disease and found that both illnesses seemed to be link to an amyloid protein buildup in the brain. In PPA, the accumulation was in the left side of the brain, which is where the language centers are. Those with Alzheimer’s had equal amounts of amyloid on both sides of the brain.

It’s a big discovery because it can help scientists better target treatment based on where these proteins accumulate first and over time. Those with PPA could be diagnosed sooner and thus they wouldn’t be given an ineffective Alzheimer’s drug.

And it’s all thanks to the new imaging technology. Before, scientists would only be able to see the amyloid buildup in the brain after death. The researchers said it was a very exciting discovery for Alzheimer’s research, as they will be able to tell if Alzheimer’s is likely causing PPA, and also be able to see it in the brain, and therefore diagnose people earlier.

“By understanding where these proteins accumulate first and over time, we can better understand the course of the disease and where to target treatment,” Emily Rogalski, the lead study investigator and research associate professor at Northwestern’s Cognitive Neurology and Alzheimer’s Disease Center (CNADC), said in the statement. “It is important to determine what Alzheimer’s looks like in PPA, because if it’s caused by something else, there is no sense in giving a patient an Alzheimer’s related drug, because it would be ineffective.”

Adam Martersteck, the first author and a graduate student in Northwestern’s neuroscience program, said in the statement that it was an exciting discovery in 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,” he 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.”