You may be wondering why some 80 to 90 year old seniors fare much better than people 20 to 30 years younger than them on memory tests.

The reason could be that these seniors have a slightly different brain makeup than others.

Based on several studies conducted by different research groups they believe it has to do with the cortex which is the outer layer of the brain involved in thinking abilities such as memory and attention. Emily Rogalski, an assistant research professor at Northwestern University’s Feinberg School of Medicine says that a thinner or a thinning cortex suggests the loss of brain cells or gray matter.

This won’t be a problem with these “SuperAgers” as dubbed by her co-scientists at Northwestern University’s Cognitive Neurology and Alzheimer’s Disease Center. These seniors have brains with a much thicker cortex (when scanned using MRI) compared to other similarly aged groups that had memory decline. And incidentally the groups with memory issues (not associated with memory decline due to Alzheimer’s disease) had brains with a thinner cortex.

Moreso these SuperAgers also have a larger cingulate cortex which is another brain region involved in attention and memory.

It is unclear if these SuperAgers were born with brains with this type of cortex or that their cortex has resisted atrophy later in life. But what is certain is that brain atrophy and loss of thinking abilities are correlated according to Dr. Russell Swerdlow, director of the Alzheimer’s Disease Center at the University of Kansas. “It could be that those whose brains are better ‘built to last’ structurally are probably those brains that are better built to last from a functional perspective, or that those who are exercising their brains may have less atrophy,” he said.

Going back to Rogalski’s study she says that Genetics are likely to play a role. “In general, a healthy lifestyle is supportive of good memory,” she adds. “But in our experience, some of our SuperAgers have been smoking a pack of cigarettes for the last 20 years. Others have never touched them. Some go to the gym three to five days a week. Others don’t exercise. Some are still working and others have never worked. It seems there might be more than one route to being a SuperAger.”

sources: everydayhealth.com & npr.org