Alzheimer’s disease is the cause of more than half of all dementia cases.

A new study, published in the journal Neurology, examined the relationship between head trauma, amyloid deposits in the brain, and neurodegeneration. Using participants from the Mayo Clinic Study of Aging, the researchers compared cognitively normal individuals to individuals with mild cognitive impairment. Among those with mild cognitive impairments, past head trauma with at least a momentary loss of consciousness was linked with greater amyloid deposits.

In an analysis of the study, Liberty Voice states that this study is unique because it is the first of such studies to be done on living subjects. In the past, similar analyses have been conducted on cadavers. BBC News describes this style of research as “pioneering.” The technique of in vivo brain scans, or brain scans conducted while the patient is still alive, could help develop novel ways of diagnosing and treating dementia.

The participants with no memory loss had normal looking brain scans. They showed healthy scans regardless of their former brain injury history. However, scans of subjects with memory loss plus a history of concussions or brain injuries were five times more likely to show early tell-tale signs of Alzheimer’s disease. What the research team discovered in the scans was a buildup of protein in the brain that has been known to be linked with Alzheimer’s.

According to an earlier National Monitor article, the majority of researchers believe two proteins are responsible for the Alzheimer’s disease: tau and beta-amyloid. In particular, these two proteins are thought to disrupt signaling between neurons during the aging process, as well as killing these proteins. A study from August 2013, published in the journal Proceedings of the National Academy of Sciences of the United States of America, examined the relationship between copper levels and incidence of the sporadic form of Alzheimer’s, finding a potential link between the severity of Alzheimer’s disease and copper levels.

Alzheimer’s is the most common source of dementia, which WebMD describes as a loss of mental capacity that is significant enough to interfere with daily functioning. Dementia is actually a group of symptoms, not a disease on its own. It is caused by an underlying disease or condition. Alzheimer’s disease is the cause of more than half of all dementia cases. WebMD reports that Alzheimer’s is often difficult to diagnose because many of the early symptoms are often accepted as routine and inevitable consequences of aging. There are some precursor conditions as well as symptoms associated with Alzheimer’s that can be treated, making early detection imperative.