Neuroscience: Does Stress Fuel Alzheimer’s disease?

Everybody gets stressed out.  However, the human body is not meant to remain in a state of stress.  Chronic stress causes more than emotion upheaval.  It could also be a factor in neurodegenerative diseases like Alzheimer’s.

It’s a well-known fact that learning to reduce stress is good for your body and your mind.  Research shows conclusively that relaxed, optimistic people have better health profiles, are happier overall, and are likely to live longer than their anxious, stressed-out counterparts.

Ideally, all of us would be able to handle negative emotions and learn how to relieve stress in constructive ways.  But in reality, few people can.  The good news is that stress management and positive thinking are skills that can be taught and learned.  And minimizing psychological distress will go a long toward improving your cognitive function – especially in old age.

The Studies

Over a decade ago, scientists began to wonder whether Alzheimer’s disease was a purely gene-driven disease, or did a person’s environment also contribute to the onset of the disease?

In 2000, Duke University researchers studied identical twins to try to accurately assess the genetic components of Alzheimer’s.  If Alzheimer’s was purely genetic then when one twin came down with it, the other one would also.  They found that this was often the case – but not always.  This led scientists to suspect that there was an environmental component to Alzheimer’s disease. 

In 2010, researchers at the University of California did a study on monkeys to determine the extent to which factors in the environment contributed to the risk of getting Alzheimer’s disease.  The research team placed some monkeys in small cages when they were young and others were placed in larger enclosures.  The monkeys in the small cages were not able to move around and get the exercise they needed and produced significantly larger amounts of stress hormones.  Upon examination of the monkeys’ brains, it was found that the monkeys in the small cages had more dementia-causing plaques in their brains – the same pathology found in human Alzheimer’s brains.

Another study at the University of Houston found that chronically-stressed rats had great difficulty learning or remembering.  These and other studies show that experiencing chronic stress over a lifetime can have some devastating consequences.

Though more research is needed, there does seem to be a link between high levels of chronic stress and neurodegenerative disease.  In other words, being stressed all the time is more than a mere emotional encumbrance.  Scientists now know that the human brain in a constant process of rewiring itself through the building and culling of synaptic connections.  And while there are known genetic dispositions for inheriting diseases like Alzheimer’s, there are also environmental factors involved in their development.  Experience – both positive and negative – has a profound effect on the brain’s ability to continue to learn, remember, and otherwise function properly.