Alzheimer's Disease: Have Researchers Identified Ground Zero?

Dementia is a blanket term that incorporates a set of symptoms that affect the brain, such as memory loss and difficulty with thinking, problem solving and language.

The most common form of dementia is Alzheimer’s disease, which is generally considered an old-age illness. However, as the Alzheimer’s Society of Canada clarifies, Alzheimer’s disease is in fact not a normal part of the aging process. Instead, it’s a fatal disease that affects many aspects of life for those who suffer from it. Each person is affected differently, and it is difficult to know which symptoms will manifest or how fast the illness will progress.

As with any disease, Alzheimer’s disease can be broken down into stages — more specifically, four stages: early, middle, late and end of life. The early stage of Alzheimer’s disease typically refers to individuals who experience mild symptoms, including forgetfulness, changes in mood and difficulty in communication. During the early stage, individuals require minimal assistance, and are for the most part functional.

In the middle stage, individuals experience a greater decline in cognitive and functional abilities. These abilities will continue to deteriorate, and individuals will require assistance with day-to-day tasks. In the late stages of the disease, individuals require constant care and lose the ability to communicate verbally. At this time, the focus shifts to ensuring individuals are comfortable.

Researchers find Alzheimer’s disease “ground zero”

Though still listed as a disease without a cure, there is no shortage of research on Alzheimer’s disease. Already, researchers have identified a genetic marker, the APOE gene, which indicates the possibility of late-onset Alzheimer’s disease. More recently, researchers have identified what they believe is the “ground zero” of where the disease starts in the brain.

The locus coeruleus has been singled out as having a significant role to play in maintaining cognitive function later in life. The region, a small, bluish part of the brainstem, releases a neurotransmitter — norepinephrine — that’s responsible for heart rate, attention, memory and cognition. Studies on mice and rats have indicated that norepinephrine is produced by the locus coeruleus, and could contribute to sheltering neurons from the factors that kill cells and accelerate Alzheimer’s disease.

University of Southern California researchers believe that the locus coeruleus “is the first brain region to show tau pathology – the slow spreading protein tangles seen early on in Alzheimer’s disease.” The team also believes that the locus coeruleus could prevent Alzheimer’s symptoms by protecting brain cells from factors like inflammation, which can accelerate the onset of dementia.

“This isn’t new research,” said Keith Fargo, director of scientific programs and outreach at the Alzheimer’s Association, adding “[t]his is scientists putting together a hypothesis based on existing research. What is new here isn’t any particular finding as much as the idea that this may explain something we call the ‘cognitive reserve effect.'”

The cognitive reverse effect, according to Fargo, is a catch-all term for a group of behaviors that are linked to an individual’s risk of Alzheimer’s disease. Fargo has explained that so far the understanding is that the more mental exercise the locus coeruleus gets, the more it produces norepinephrine, giving the brain more protection against Alzheimer’s disease.

While Fargo has suggested that the research is not new, identifying the ground zero of Alzheimer’s disease is a big step in the right direction, and should give experts further insight into a disease that to date only has treatments and no cure.

Securities Disclosure: I, Vivien Diniz, hold no direct investment interest in any company mentioned in this article.