Dubbed by one scientist as, "probably the most important paper to be published in the field of dementia in the last five years," a team of researchers has described a newly defined neurodegenerative disease that closely mimics the symptoms of Alzheimer's, but which has an entirely different pathological cause.

Following a constant parade of failed clinical trials some researchers are reconsidering many of the basic foundations that underpin the mainstream consensus on Alzheimer's disease science. Toxic accumulations of amyloid and tau proteins have generally been considered the pathological hallmark of Alzheimer's disease and its related dementia but recently a variety of competing hypotheses have been raised.

This new study stemmed from the observation that while all patients with Alzheimer's may display some kind of dementia, not all patients displaying symptoms of dementia necessarily suffer from Alzheimer's.

"Recent research and clinical trials in Alzheimer's disease have taught us two things: First, not all of the people we thought had Alzheimer's have it; second, it is very important to understand the other contributors to dementia," explains Nina Silverberg, from the National Institute on Aging.

In a recently published report, the researchers describe a newly defined brain disorder called limbic-predominant age-related TDP-43 encephalopathy, or LATE. This disorder results in symptoms of dementia that significantly resemble Alzheimer's disease, however, the pathological signs in the brain are completely different.