This piece1 is informative and offers some good advice, but is woefully deficient in some areas that should have been included. The article is basically an annotated diagram that begins with the first step of the eye seeing something. The second step is the information arriving at the visual cortex that identifies what the eyes see. The third step is the information flowing through the associative cortex to develop further understanding. The fourth step is the information arriving at the hippocampus (actually it should be hippocampi as there is one hippocampus in each hemisphere of the brain. Information must be processed by these hippocampi if it is to be recalled later. People who have lost their hippocampi via surgery, accidents, or dementia, are unable to learn/remember new information. But it is the prefrontal cortext decides whether this new information warrants processing by the hippocampi for later use. The prefrontal cortex is an important part of the brain as it not only decides what is worth remembering, but it is involved in all the decisions we make and is responsible for regulating our behavior. Unfortunately, it is late maturing (not until our twenties) and early to decline (sometime after age 50). So far this description is accurate and it is understood that there would be similar, but not identical stages of processing for other modalities of information.
There is another section of the article on how to slow the effects of aging that provides the following advice:
Calm Down – this is good advice as the piece correctly states that stress can destroy synapses , it fouls up the hippocampus and the prefrontal cortex. It does not mention that the various types of meditation are beneficial in helping us to calm down.
Exercise – this is good advice as the increased blood flow and oxygen uptake it engenders is beneficial to the brain.
Make friends – more good advice. There have been a number of Healthymemory Blog Post extolling the benefits of socialization.
Sleep well – more good advice. Getting adequate sleep is important not only to general health, but is also critical to important brain and memory processes.
Ask about estrogen – Ladies, you can judge this one for yourselves. This recommendation is based on one study. Given the somewhat uneven results from estrogen therapies, some skepticism might be in order.
Do what you do best – Although it is true that expertise is maintained well into old age and that you are less likely to lose what you know well, it is a somewhat misleading strategy for slowing the effects of aging. Although it is fine to continuing growing in your area of expertise, it would be a mistake not to expand into some new areas. Research has indicated that maintaining brain and cognitive health should not be a reactive, defensive matter, but rather a proactive effort to continue growing cognitive competence.
An interesting question to ask, is why does the prefrontal cortex start to decline after age 50? Is it solely a matter of aging? There is the Dumbledore Hypothesis regarding the effects of aging on the brain (See the Healthymemory Blog posts, “More on Attention and Cognitive Control,”, “Passing 65,” and “Memory and Aging.). This hypothesis fits well with the Two System View of Cognition (see the Healthymemory Blog post “The Two System View of Cognition.”). According to this view, there are two primary means of processing information. System One is fast and automatic. It is the result of prior learning. This is the system that is doing the majority of the processing when we converse, drive a car, etc. System Two is slow, effortful, and demands attention. This is what is at work when we are trying to learning something new, to solve a math problem, or recognize something that is illogical or contradictory in what the person we are conversing with has said (or in our own conversation if we recognize something illogical or contradictory in what we have said. According to the Dumbledore Hypothesis as we age we increasingly rely on System One processing because we have learned much and don’t need to do as much processing as a younger person who does not have such a wealth of experience to draw upon. The problem is that since we do less System Two processing we use our prefrontal cortex less. The use it or lose it advice that we know from physical exercise also applies to cognitive exercise. When we use our prefrontal cortex more glucose is sent there. So the loss in the functioning in the prefrontal cortex might not be solely do to aging. It might be in part, perhaps in large part, to a loss in the frequency of its use.
So the new idea is to challenge our minds and to continue to learn new things as we age. (See the Healthymemory Blog post, “A Quote Worth Pondering.”) It is not too late to learn a new language, or new subject matter. These activities will engage the prefrontal cortex. Mnemonic techniques have the benefit of not only being a technique that enhances memory, but are also means of providing cognitive exercise that exercises the prefrontal cortex and activates both cortices of the brain. So aging should not cause us to be reactive and defensive, but we should go on offense, be proactive, and continue to grow cognitively.