My brain health lifestyle ® advocates remaining integrated and involved with personally relevant roles across your lifespan. Retirement, defined from a traditional sense, suggests the opposite and seems to advocate a withdrawal from society, a tendency towards isolation and passive existence. Surveys indicate baby boomers (those born between 1946 and 1964) will not rely on the traditional form of retirement and instead will redefine their roles several times as they get older. This is most likely a very positive sign from a brain health perspective.

My thought is that an active and stimulated brain is healthy. Studies in animals have shown the relationship between socialization and mental stimulation and structural and functional brain health. There have also been plenty of studies to show a similar relationship in humans. While there is not a cause and effect, we should not underestimate the value of the relationship.

A recent study published in the Journal of Economic Perspectives suggests that the earlier people retire, the more quickly their memory ability erodes. Data was gathered from the United States and 11 European countries as part of an NIA study that began 20 years ago. 22,000 or more Americans 50 years of age and older were surveyed every two years and administered memory tests. This led Europeans to do their own surveys using similar questions so the data could be compared.

The memory test measured free recall of a list of 10 nouns immediately after presentation and then again 10 minutes after they were first presented. Respondents in the United States scored an average of 11/20 while those in Europe recalled less. The authors of the study noticed large differences in the years people retired. In the U.S., England, and Denmark, retirement 65 to 70% of men were still working in their 60s. In France and Italy, the figure is 10 to 20% and 38% in Spain.

Researchers found a direct relationship between percentage of persons in a nation who are working at age 60-64 and their performance on memory tests. The longer people in a country keep working, the better, as a group, they do on tests when they are in their early 60s.

More work is needed to better understand the multiple factors that can play a role in this significant relationship. However, it appears clear that work remains a positive aspect or function to health as we get older and fits with the idea that remaining integrated and involved with personal meaningful roles is beneficial to brain health

Interest in the human brain is at an all time high with both scientists and the general public reading, learning, and writing more about this great system. There is much discussion and even tension about what the brain can and cannot do, whether it has certain capacities or not, and what can be stated with some confidence and what cannot.

While it is true we need to conduct more, well designed, controlled studies, certain things are true of the brain today:

1.    The human brain is the most complicated and brilliant system known.
2.    The human brain has plasticity which means it can be shaped, is dynamic, and constantly reorganizing.
3.    The human brain generates brain cells in the hippocampus and most likely the olfactory system.
4.    Cognition changes as we get older, but there remains great variability particularly at the oldest of age.
5.    Proactive lifestyle factors relate to improved brain health.
6.    Brain reserve continues to gain support as a mechanism to delay onset of dementia.

The latter point was reinforced yesterday in a major article in the USA Today (9-2-10) that described a study that will be published in Neurology. A research team at Rush Presbyterian conducted a 12 year study that evaluated the mental activities of 1,157 people 65 years of age and older who did not demonstrate dementia at the start of the study. Study participants were assessed at the beginning of the study and again for Alzheimer’s at the six-year period. After that, each participated was evaluated every three years to measure how often they participated in activities such as reading, listening to the radio, playing games and going to the museum. A five point scale was used with more points earned for more frequent participation in mentally stimulating activities.

Results indicated the rate of cognitive decline for persons without dementia was reduced by 52% for each point on the cognitive activity scale. For persons with Alzheimer’s the average rate of decline per year increased by 42% for each point on the same scale. The research team described their findings using the cognitive construct of “cognitive or brain reserve” which suggests that an active and stimulated brain creates new neural pathways which over time can help to delay onset of neurodegenerative diseases such as Alzheimer’s. This is not a cure.

Researchers were less clear why persons who are mentally active demonstrate a rapid decline once Alzheimer’s manifests. One idea might be that reserve helps to delay onset of Alzheimer’s, but once the disease manifests clinically it is already in an advanced stage with an accelerated rate of decline. The good news for this study is that there is benefit to the brain from remaining mentally stimulated across the lifespan. Brain reserve is something worth building.