Marian C. Diamond’s groundbreaking research on the plasticity of the rat brain in the early 60´s was initially met with skepticism. However, time has certainly proven her right. And we now know that it is not only the rat brain that is plastic but the human brain as well. The plasticity of the human brain is now an accepted fact. We are also aware of the considerable variability in how well different brains cope with pathology. In order to explain this interindividual difference we use the concept of “cognitive reserve”.
In November 2014 María K. Jónsdóttir, Ph.D. in clinical neuropsychology and one of the organizers of an Icelandic blog site about “brain health” (http://heilahreysti.about-brains.com), gave a talk on cognitive reserve and the various claims that have been made about how it can be increased in order to bolster brain health, at a symposium organized by the University of Iceland’s Centre for Ethics in Reykjavík.
Jón Bragi Pálsson interviewed María K. Jónsdóttir.
How is cognitive reserve best described and how important is it for us in preserving our mental health and brain function?
Cognitive reserve is a hypothetical construct that was developed to explain the discrepancy we observe between the state of the brain and a person´s cognition and ability to function in daily life. In other words, there is not a direct relationship between brain pathology and cognitive impairment or whether a person has been diagnosed with a disease such as Alzheimer´s dementia. Some people might, for example, have considerable Alzheimer pathology in the brain, yet still be cognitively fit and function well in their daily life. Those people are said to have high cognitive reserve, which protects them against the ravages of the pathology. A person with less pathology who quickly disintegrates and is diagnosed with Alzheimer dementia much earlier in the disease process is said to have little cognitive reserve.
What is the most sensible method, in your opinion, for a normal healthy person to increase his cognitive reserve in order to decrease the risk of developing neurodegenerative diseases?
There are many things that contribute to cognitive reserve and their effects accumulate during our lives. Among them are things that we obviously do not have control over, such as our genetic make-up. But we can make life-style choices that positively or negatively influence cognitive reserve. Regular exercise would for example generally be associated with better cognitive reserve. High educational and occupational attainment and good general health also contributes to increased cognitive reserve. I want to emphasize that maintaining a healthy brain is a life-long enterprise. It is also important to emphasize that the human brain remains plastic into old age. So, it is never too late to start and research has shown that exercising and keeping socially active in later life can make a difference.
There is a lot of hype about certain food supplements and there is even a food supplement that has been marketed under the name of “Cognitive reserve”. But cognitive reserve does not come in a bottle! Neither does sitting alone doing similar crossword puzzles and Sudoku over and over again do the trick all by itself. However, people want quick fixes and my patients frequently ask me about helpful food supplements. I always tell them the same thing: exercise regularly and with as much intensity as you can, eat a healthy diet and not too much, make sure to sleep well, avoid too much stress, meditate if possible, stimulate your brain by learning new things and challenging yourself and spend time with loved ones and friends. This is much more helpful, and probably also makes you happier than spending your free time playing computer games or sitting alone solving crossword puzzles. I also believe that we should teach our children about the importance of brain health from an early age and how we can all maximize our chances of maintaining a healthy brain and thus increase our quality of life, as we grow older. We take our children to the dentist from an early age and we teach them about eating right in order to keep physically healthy. But we generally leave the brain out of the discussion. However, we should explicitly teach them about the importance of taking care of our brain, just as we teach them to brush their teeth. We will never eradicate all dementia cases but we can probably do better than we are doing now.
A lot of specialized brain stimulating computer games and apps, that claim to be scientifically approved, are available on the Internet. Are these games helpful in increasing cognitive reserve?
Most of the games have not been put to a strict scientific test and the studies already out are not very convincing in my view. Of course you become better at computer games if you practice regularly and I have nothing against computer games per se. But do those skills transfer into everyday activities? It can also possibly give people a false sense of security to play video games every day; they feel they are doing something really wondrous for their brain. Yet, to play video games to the exclusion of other brain-protecting activities, such as exercising regularly or enjoying an active social life where you interact with others, have nice conversations, participate in a book club or play golf, is not recommended. However, playing video games is certainly fine if people enjoy them. But it is not the sole answer!