January 6, 2012

Good News for Senior Brains!

So often, we read studies about cognitive decline in seniors. We almost take those results for granted, don’t  we? You age, your hair turns gray, you lose mental abilities.

But wait! As we enter a new year, I’ve just seen a couple studies about the senior brain that suggest: "Not so fast!”

The Cautious, Trainable Senior Brain
The December 27, 2011 issue of the e-bulletin ScienceDaily reports on an interesting study conducted by researchers at the University of Ohio. Essentially, the scientists drew several conclusions:
  • While senior brains may initially take longer than younger brains to make quick decisions in some situations, it’s often because the older study subjects consciously decide to make good, accurate decisions. Their brains have decided that being right is more important than being fast.
  • Those same senior brains that were purposely deliberating about decisions can be TRAINED to act faster, in effect damping down that tendency for accuracy. With training, those older brains essentially acquired the same speed as younger brains, without a significant corresponding drop in accuracy.

Study leaders used two different tests. In the first, subjects sitting at computer screens were asked to decide whether they saw a “small” number (31-50) of asterisks, or a “large” number (51-70).

In the second test, subjects saw strings of letters on their screens, and were asked to decide if they were actual English words. Some of those strings of letters were easy – just random letters placed together – and others, like “nerse,” were a little tougher, since they were pronounceable, and may even have resembled real words.

Said Ohio State University psychology professor and study co-author Roger Ratcliff: “Many people think that it is just natural for older people's brains to slow down as they age, but we're finding that isn't always true. At least in some situations, 70-year-olds may have response times similar to those of 25-year olds."

Victory for seniors! (See "ScienceDaily" 12/27/11.)

The Adapting, Efficient Senior Brain
In a similar study conducted at the University Geriatrics Institute of Montreal and reported in ScienceDaily on August 25, 2011, researchers found that senior brains adapted to test changes in ways younger brains did not.

Study subjects were asked to pair words according to specified guidelines from larger groups of words. For example, subjects might be asked to find two words that started the same way, or two words that rhymed, or two words from a similar category (like “animals”). Subjects would choose their answer pair, and could continue to the next group when they answered correctly.

Here’s where things got interesting: the researchers would occasionally change the parameters without advising their subjects, i.e., the correct new pairing would be based, for example, not on “animals” but on something else, like words that rhyme.

Interestingly, senior study subjects seemed to handle the unannounced guideline changes – and the obvious setbacks they created – better than their younger counterparts. Explained study co-author Dr. Oury Monchi:
Funny enough, the young brain is more reactive to negative reinforcement than the older one. When the young participants made a mistake and had to plan and execute a new strategy to get the right answer, various parts of their brains were recruited even before the next task began. However, when the older participants learned that they had made a mistake, these regions were only recruited at the beginning of the next trial, indicating that with age, we decide to make adjustments only when absolutely necessary. It is as though the older brain is more impervious to criticism and more confident than the young brain.
Added Monchi:
We now have neurobiological evidence showing that with age comes wisdom and that as the brain gets older, it learns to better allocate its resources. Overall, our study shows that Aesop's fable about the tortoise and the hare was on the money: being able to run fast does not always win the race -- you have to know how to best use your abilities. This adage is a defining characteristic of aging.
See "ScienceDaily" 8/25/11.

So -- into another year we go… a year in which we have the opportunity not to get older, but to get better, smarter, more adaptive, wiser.

Senior power!
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