It’s apparent that the aging process affects everyone
differently. Some individuals reach their 60s exhibiting little to no gray
hair. Some people wrinkle much faster than others. Thus, it goes without saying
that the same is true with mental aging. These group of people, whose mental
age is much younger than their chronological age are known as Super-agers.
Tamar Gefen, a researcher at Northwestern University, spoke
to Loyola Students about these amazing individuals. Super-agers are defined as
80+ year old individuals whose memory functions at a level equal to or superior
to those who are 20-30 years younger. In the study she conducted with her
colleagues, a memory test was given to the Super-agers, elderly controls, and
50-65 year olds. The memory test included a list of 15 words, which individuals
were supposed to list as many as they could remember 30 minutes later. The
Super-agers performed far better than the elderly controls, who were of the
same age. Furthermore, they were able to remember just as many words as the
50-65 year olds. Researchers were amazed by the results, so they performed MRI
studies to see what accounted for the difference between the groups.
Between the three
groups, it was observed that the group of Super-agers exhibited “a region of
anterior cingulate cortex that was thicker compared with healthy 50- to 65-
year olds (Gefen et al., 2015). Within the anterior cingulate regions of
Super-agers is a high density of von Economo neurons (VEN). These neurons are
relatively large cells that allow for rapid communication between sections of
the brain.
Dr. John Allman at Caltach is a leader in the investigation
of VENs. Through studies, it was found that only humans, apes, whales, and
elephants express VENs. Interestingly, humans have over twice the number of
apes, our closest evolutionary neighbor. It is argued that VENs are what make
us uniquely human. Furthermore, not all VENs are in place when we are born.
Only 15% of these cells seem to be present at birth and takes numerous years
before adult-like levels are achieved. What is not known is if other existing
cell types that are present at birth are converting into VENs or if new neurons
are traveling into place. It’s possible that there is some genetic component
for the expression of VENs. If this is the case, then we might be able to
control gene expression so that more neurons convert or more neurons travel
into place, depending on the mechanism by which VENs arise.
Nowadays, many people are looking for ways to living longer,
while also being able to live better. However, people don’t want to live a life
where they are unable to walk or remember something they said 5 minutes ago.
The presence of Super-agers gives hope that it is possible to do this.
Sources:
Morphometric and
histologic substrates of cingulate integrity in elders with exceptional memory
capacity. (Gefen et at., 2015)
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