My mother-in-law just turned 89. She still lives alone in a ranch-style home in a gated community and was able to renew her drivers’ license, albeit without the privilege of driving at night. Other people her age are struggling with dementia. As people age, the variability in cognitive functions, especially memory, widens. A group of 20-somethings will perform much more similarly on tests or tasks measuring attention, memory, and speed-of processing than will a group of 70-somethings. The question we all ask is, “Why?”
The answer is not clear, but to learn more about this conundrum, some researchers are studying a group referred to as “SuperAgers.” These are adults over age 80 whose performance on tests of episodic memory is at least as good as that of people 20 to 30 years younger, and they are being studied by researchers at the Northwestern University SuperAging Program, Massachusetts General Hospital and Harvard Medical School. Neuroimaging findings also suggest that the brains of these SuperAgers may be physiologically different than those of us who do not fall into that category.
In a study reported in the Journal of Neuroscience (September 2016), researchers tested the hypothesis that the brains of SuperAgers would look more like those of younger people, especially in the networks involved in memory. They found that the SuperAgers performed similarly to younger adults on tests of memory, and that they did not show patterns of brain atrophy usually found in older adults. The brain regions of interest in this study were mostly in the default mode network (associated with memory encoding, storage and retrieval) and the salience network (associated with attention and executive function).
The researchers concluded that SuperAgers perform better than most older adults in attentional and executive control processes involved in memory encoding and retrieval, and in memory storage. They also found that the SuperAgers had fully preserved hippocampal volume and cortical thickness, while typical older adults exhibited smaller volumes, even when matched for educational level.
A question regarding SuperAgers is whether their outstanding performance is due to a lack of cognitive decline, or whether they perhaps were higher functioning at younger ages, but longitudinal studies would be necessary to answer that question.
The question of most interest, however, is: How does one become a SuperAger? What behaviors and lifestyle practices will increase one’s chances of remaining mentally sharp in older age? Researchers in one study suggested it is a simple as working hard at something. It appears that both vigorous physical exercise and strenuous mental effort can help keep the relevant brain regions thick and healthy.
One of the challenges of doing this is that engaging in serious exercise or demanding cognitive tasks may lessen one’s motivation to continue pursuit of those activities. I know that whenever I attempt to do a Sudoku, which usually ends in failure, it lessens my desire to do another. The Marine Corps motto, “Pain is weakness leaving the body,” suggests that the discomfort of exertion means you’re building muscle and discipline. A characteristic of SuperAgers is that they continue exerting effort despite unpleasantness, resulting in a more youthful brain that helps maintain a better ability to pay attention and a more reliable memory.
The brain tends to like familiarity and pattern and prefers to do what it knows how to do. Learning a foreign language or how to play a musical instrument, trying to do tasks with your non-dominant hand, and engaging in physical exercise are all ways to challenge your brain and make it work harder. Use it or lose it is apropos here, because brain tissue gets thinner from disuse, so using it may help it stay thick in the important places as you age.