Super Brains and Dementia

We have a lot of evidence showing that the older you get the more problems we start having with our brains. In healthy adults they tend to shrink, and then they become prone to diseases, not excluding our nemesis of Alzheimer’s disease. We always assumed that these changes are fixed.  But then how do we explain exceptional older adults.

Exceptional adults are examples of what is possible, and not what is statistically likely.

When Emily Rogalski from Northwestern University looked at two groups of Chicago-area older adults of 80 years and older with similar education--12 who had exceptional memory, and ten normal older adults--she was not ready for the findings.  Her study reported that the exceptional group not only had sharp memories--as sharp as people 20 to 30 years younger--but she also found that their brains appear younger.  When compared to 50 to 65 year olds, these exceptional older adults had a thicker outer layer of the brain important for memory, attention and other thinking abilities. While in another region deep in the brain, they had thicker anterior cingulate--which is responsible for attention. Not only was there no shrinkage, these exceptional older adults show youthful brains.

Henrikje van Andel-Schipper was the oldest woman in the world when she died at age 115 in 2005. After Gert Holstege, from Groningen University, undertook a post-mortem of her brain he found few signs of Alzheimer's or other diseases. It seems that these exceptional people have escaped the normal effects of aging.

Jessica Evert from Ohio State University and her colleagues support this view. When examining death from heart disease, nonskin cancer, and stroke, 87% of male and 83% of female centenarians that they studied delayed or escaped these diseases.

If we apply the concept of escapers to the brain, then we can say that exceptional older adults escape from damaging their brain.  As far-fetched as this might seem, researchers are now focusing on studying how we might be developing the brain in detrimental ways. Known as negative plasticity—by not exercising the brain, learning things the wrong way and responding to stress—could be  causing the brain to shrink and develop inefficiently. 

Although brain shrinkage is related to aging, we now know it is not fixed and invariable. If the brain shrinks because of trauma that we impose upon it, then we need to start taking better care of our brain. The brain likes to be challenged, to be happy, stress free, fed well and exercised--just like a precious teen.

Mario Garrett, Ph.D., is a professor of gerontology at San Diego State University and can be reached at mariusgarrett@yahoo.com