Alzheimer’s disease is an irreversible, progressive brain disorder that causes a person’s memory to degenerate gradually. Onset generally occurs in older adulthood and estimates suggest that approximately 14.9% of Canadians over the age of 65 are affected by the disease or some other form of dementia. Alzheimer’s can be a particularly catastrophic disease that can cause a person to forfeit their memories and in turn lose the person that they used to be, causing significant distress for the individual as well those closest to them. There is no known cure for the disease and treatment is often complex and comprised of medication and behavioural training components. In working towards a cure, neuroscientific researchers have aimed to increase their understanding of the disease by examining the various components of the brain using neuroimaging techniques.
Until recently, relatively little was known about what parts of the brain were involved in the degenerative processes that occur in Alzheimer’s. Researchers from the University of Southern California have however just published ground-breaking research that appears to have localised a small part of the brain named the locus coeruleus to be the centre of the disease. The locus coeruleus releases a chemical called norepinephrine that helps to regulate heart-rate, attention, memory and cognition. According to lead author Mara Mather, this part of the brain is the first region where tau pathology, a protein that causes tangling of neurons, shows up. Build-up of this protein can lead to the adverse effects associated with Alzheimer’s. It is also a vulnerable area in that its connectedness means that it is more sensitive to toxins and infections than other more closed areas of the brain.
Though this research does not comprehensively tell us how to treat the disease, its significance comes from the fact that it furthers our ability to understand the processes that contribute to the condition. It also appears to confirm much of what researchers believe to be true about something termed the cognitive reserve. The cognitive reserve which refers to the brain’s resilience to damage and disease has been associated with activation of the locus coeruleus. Experts believe that the cognitive reserve is impacted by certain behaviours such as learning new skills. These behaviours cause norepinephrine to be released which helps to protect the cells in the area. This association therefore suggests that participation in such behaviours may potentially buffer the onset of neurodegenerative diseases such as Alzheimer’s.
This research offers further insight into a complex disorder that is becoming an increasing problem in our aging population. By identifying where in the brain Alzheimer’s occurs, researchers can now move closer towards understanding how to develop effective treatment options for the condition.
You can access the full article here.
Ms. Niamh Allen, M.A. B.Sc.