They say the eyes are the window to the soul, but new research suggests your eyes may be the window to an early Alzheimer’s disease diagnosis.

That’s because Alzheimer’s affects the retina, or the back of the eye, in a similar way to how the disease affects the brain, according to neuroscience researchers at Cedars-Sinai Medical Center in California. A high-definition eye scan revealed to the researchers a buildup of toxic proteins, which have been connected to Alzheimer’s.

“The findings suggest that the retina may serve as a reliable source for Alzheimer’s disease diagnosis,” Cedars-Sinai associate professor and lead author of the study Maya Koronyo-Hamaoui told USA Today. “One of the major advantages of analyzing the retina is the repeatability, which allows us to monitor patients and potentially the progression of their disease.”

When it comes to early Alzheimer’s detection, the results of the study could be groundbreaking. Recently, expensive brain scans have been the norm for detection, and before that, diagnosis only came from brain inspections once someone had died.

“Our hope is that eventually the investigational eye scan will be used as a screening device to detect the disease early enough to intervene and change the course of the disorder with medications and lifestyle changes,” said Keith L. Black, co-leader of the study and chair of the Cedars-Sinai Department of Neurosurgery.

In addition to the toxic protein buildup, the study found plaques in regions of the retina that go unchecked. The amount of plaque uncovered matched the plaque in certain areas of the brain.

“Now we know exactly where to look to find the signs of Alzheimer’s disease as early as possible,” Black said.

The study was published in the journal JCI Insight.