Can Cognitive Reserve Combat Depression as Well as Dementia?
Maybe. And what a wonderful tool that would be for enhancing emotional as well as physical well-being.
What is cognitive reserve, anyway? It refers to the brain's resilience in the face of neurological changes that often lead to conditions such as dementia. Think of cognitive reserve like an immune system. If your immune system is strong, then you're likely to fare better when exposed to illness. You might not get sick at all - and if you do, it might not be as severe as it would be with a weak immune system.
The same concept applies to cognitive reserve. If our brain has lots of healthy neurons and an abundance of good connections between those neurons, we're likely to fare better even if some of those neurons get damaged or if a disease process makes it difficult for them to communicate with each other. On the other hand, if our brain doesn't have a lot of neuronal reserve built up, we're likely to be more vulnerable to conditions that damage brain cells.
We already know that cognitive reserve can stave off dementia, at least for a while. But what hasn't been explored - until recently, that is - is whether cognitive reserve can also protect us against depression.
To explore this, researchers from Wayne State University and multiple Veterans Administration health care centers followed 1,355 women aged 80 years and older for 6 years. The team looked at educational attainment, cerebrovascular health, cognitive status, and depression.
Some of the variables may seem random, but the researchers had done their homework. Research shows that a good predictor of cognitive reserve is the level of educational attainment a person has achieved. Also, cerebrovascular health has been found to be linked to risk for depression.
Interestingly, the researchers found that greater educational attainment was associated with fewer depressive symptoms, but this relationship weakened over time when cerebrovascular health declined. The researchers proposed that cognitive reserve may protect mood in later life.
I liked this study, but I question whether educational attainment is the only indicator of cognitive reserve. Lifelong education that doesn't occur in the classroom seems like a viable way to keep the brain healthy as well, as does trying new things, traveling, and generally seeking novelty in life. Still, the study is encouraging in that we've gleaned a new way to possibly delay or prevent the debilitating effects of a disease as serious as depression.
Paulson, D., Bowen, M. E., Lichtenberg, P.A. (2013). Does brain reserve protect older women from vascular depression? The Journals of Gerontology: Series B, Advance Access, doi: 10.1093/geronb/gbt007