For years researchers have tried to understand the impact and significance of a person's education level on the development of Alzheimer's disease. Many studies have shown that people who often challenge themselves to learn complex tasks will show Alzheimer’s symptoms later than those who don’t. Scientists theorized that people who work to enrich their minds, whether through formal means or through a mentally challenging lifestyle, have more cognitive resources at their disposal to mask symptoms of AD.
Now, an article in the Harvard Gazette reports on a study showing evidence that continually challenging our minds may be an even more powerful ally against AD symptoms than previously thought.
This study, led by Dennis Selkoe, co-director of the Center for Neurologic Diseases in the Department of Neurology at Brigham and Women’s Hospital (BWH), provides “specific, pre-clinical scientific evidence supporting the concept that prolonged and intensive stimulation by an enriched environment — especially regular exposure to new activities — may have beneficial effects in delaying one of the key negative factors in Alzheimer’s disease.” That key factor is weakened communication between nerve cells affecting memory. This study seems to suggest that actual brain protection rather than simply the ability to mask symptoms may be at work in people with highly challenged brains.
Changes in the brain
Alzheimer’s disease is thought to occur when amyloid beta protein accumulates and forms plaques in the brain which can block nerve cells from properly communicating with one another. This poor communication may gradually lead to the erosion of a person’s mental processes, such as memory, attention, and the ability to learn, understand, and process information.
Selkoe and his team found that “prolonged exposure to an enriched environment activated certain adrenalin-related brain receptors. The activity triggered a signaling pathway that prevented the amyloid beta protein from weakening the communication between nerve cells in the brain’s ‘memory center,’ the hippocampus.”
There are likely many factors at work in Alzheimer's development, and this study is just looking at one element, however Selkoe did say that their work points “… to basic scientific reasons for the apparent lessening of [Alzheimer’s disease] risk in people with cognitively richer and more complex experiences during life.”
What about brilliant, educated people who develop Alzheimer’s?
Scientists don’t yet know exactly when Alzheimer’s disease begins to develop in each individual, but studies are increasingly offering the theory that the disease begins decades before symptoms are exhibited. Therefore, it’s quite possible that people who’ve lived a life full of creative mental challenges have had the disease for decades, but symptoms didn’t become obvious because they had an increased ability to mask the symptoms. Or, it could be that they simply developed the disease at a later age because of the protective power of an enriched environment. It will likely take much additional research before there is certainty about this issue.