Happy New Year and welcome to Season 2 of “Mistakes On The Journey To Nowhere!”
I thought I’d kick things off on a positive note with a discussion about brain resilience and cognitive reserve. The two terms are somewhat interchangeable and they both point in the same direction: factors that can protect us in the presence of dementia pathology.
There is a wealth of research associating the presence of beta amyloid and tau proteins with the occurrence of dementia. That is why many drug companies are searching for ways to remove these deposits as a way to slow down or eliminate them as a risk factor.
However, there is one finding that points in another direction. About 30% of those with high levels of these damaging chemicals (as determined by autopsy after their deaths) never developed dementia while they were alive.
How can that be? Either the whole plaques/tangles/beta/tau hypothesis is wrong, or these folks possessed some quality that enabled them to function at a high cognitive level in spite of the damage that had been done to their brains. The latter appears to be the case.
So what is it that allows about ⅓ of us with dementia pathology to escape its ravages? As with most dementia research, the findings are correlational and not yet proven to be causal, but they all seem to lead in the same direction: it helps to grow lots of neurons and stimulate the production of synapses and neural networks throughout your lifetime. Later in life, then, when a given pathway is short-circuited by a chemical blockage, your brain is able to use an alternate route to complete the task. It’s a little like taking back roads when there is a car accident and traffic is backed up on the interstate.
The ability to do this is referred to as brain resilience or cognitive reserve.
As always, there seems to be a genetic component with some of us hard-wired to grow more connections and have larger brains. But, as always, a lot of it is environmental and behavioral, too.
Having gone to an academically stimulating elementary school is helpful. So, too, is having a college degree, as compared to those with only a high school education. Having a cognitively complex job (as opposed to performing manual labor or having a repetitive factory job) builds resilience. Learning new things at any age is protective.
Looking back over my life, it looks like I was very fortunate, indeed. I attended high-quality elementary and high schools and then received my undergraduate degree in Economics from Brown University. When I was 44, I returned to graduate school for my masters and Ph.D. in clinical psychology. That was 6 years of the most intense brain-stimulating work imaginable leading to a cognitively challenging career.
In fact, I’ve re-trained 5 times over my life to pursue new careers (urban planner, performing arts center director, B&B host, clinical psychologist and political operative). And now I’m trying to teach myself how to play the recorder!
Let’s follow this building-more-brain-cells-and-connections path to promote resilience a little further. It’s not just lifelong learning that does it. It turns out that exercise also creates new connections in wide areas of the brain. Who knew? So it turns out that my running for 57 years probably also increased my cognitive resilience. Too bad it never made me any faster!
BTW: exercise also helps promote the formation of the myelin sheath that protects the brain’s pathways which should, in turn, help reduce the short-circuiting we all experience from time to time because the electrical signal traveling down that pathway will have a greater likelihood of reaching its destination at full force.
(Caveat emptor: You might see ads for supplements intended to increase the production of Nerve Growth Factor (NGF) in order to facilitate these results. From what I can tell, the research is really preliminary on this and these products are jumping the gun a bit.)
So the very good news here is that the brain retains its ability to create new cells (neurogenesis) and to re-wire itself (plasticity) to the very end. By constantly seeking out new learning opportunities and exercising, we can increase our brain’s chances (resilience) of overcoming the insults we’ve inflicted upon it over the years.