Research Hit: Stress Knocks Out Your Cognitive Reserve
Physiological stress seems to reduce the positive impact of cognitive reserve on neurodegeneration
Ok, we know stress is bad for you but what do you mean by cognitive reserve?
The concept of cognitive reserve goes back to some famous studies in the 1980s. In this older people’s brains were scanned (in one particularly well known case the brains of nuns).
Some of these people’s brain scans showed brains that seemed to be advanced stages of various forms of dementia, however, they seemed to be still highly functional. This mismatch confused researchers.
They then surmised, by looking at their lives, and cognitive and mental activities, that some people who led active, interesting lives, and kept cognitively active developed a “cognitive reserve”.
This reserve seems to protect individuals from the cognitive and mental decline even if the brain is showing signs of neurodegeneration.
And how does stress impact this then? Doesn’t stress increase degeneration?
This is precisely what Manasa Shanta Yerramalla of the Karolinska Institutet in Sweden wanted to find out.
To do this they studied a group of 113 elderly people at the memory clinic at the Karolinska University Hospital. They examined the relationship between cognitive reserve, cognition and various biomarkers for Alzheimer’s disease. But they also measured stress, perceived stress i.e. how much people thought they were stressed and physiologically i.e. by the body’s stress response through cortisol in saliva.
And the results?
As expected cognitive reserve improved cognition. That we already know. But physiological stress (not perceived stress) reduced this link. Basically stress eats up your cognitive reserve.
And back to cognitive reserve - how can we increase this?
Yes, obviously it is a very good thing to have and I have previously reported on some of these aspects previously:
A lot of these are under our own control but some come with various socio-economic factors. Basically having a cognitively stimulating and enriching life:
Use your brain, a lot
Have a cognitively challenging job, if possible, if not go back to 1.
Keep learning, all your life
Keep physically active, all your life
Have a wide range of leisure activities, all your life
Have healthy and multiple social interactions, all your life
Of note, another piece just out, by Miguel Ramos et al of the University of Birmingham (UK - yay my hometown), also found that having a varied social network increases wellbeing.
But this research shows that stress management strategies are also important. But a lot of the above are also stress management activities - a walk in nature for example.
Ok, so how do you build cognitive reserve if you are already older?
The exact same applies - I have also reported on research that shows just how beneficial, for example, exercise can be in older age and for healthy ageing.
Obviously it is better if you can build cognitive reserve all our life - but starting at any time will still help. Maybe a lot!
Will writing and reading articles on the brain help?
That’s why I do it!
And your running advice also seems to hold true!
Yes, you don’t stop running because you get old. You get old because you stop running! You can apply that to many things.
Reference
Manasa Shanta Yerramalla, Alexander Darin‐Mattsson, Chinedu T Udeh‐Momoh, et al.
Cognitive reserve, cortisol, and Alzheimer's disease biomarkers: A memory clinic study.
Alzheimer's & Dementia, 2024
DOI: 10.1002/alz.13866
Miguel R. Ramos, Danying Li, Matthew R. Bennett, et al.
Variety Is the Spice of Life: Diverse Social Networks Are Associated With Social Cohesion and Well-Being.
Psychological Science, 2024
DOI: 10.1177/09567976241243370