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According to a paper recently published in "Nature Human Behavior" by a team of researchers from the US and Portugal, two key brain functions improve with age. (Pixabay)

It's generally assumed that aging brings the deterioration not only of our physical strength but also our mental ability. But it seems that not all our brain functions decline with age.

According to a paper recently published in "Nature Human Behavior" by a team of researchers from the US and Portugal, two key brain functions actually improve with age, rather like aged whiskey.

These two functions "allow us to attend to new information and to focus on what's important in a given situation," the Georgetown University Medical Center said in a news release.

"These functions underlie critical aspects of cognition such as memory, decision making, and self-control, and even navigation, math, language and reading."

One of the main authors in the study is Michael T. Ullman, a professor of neuroscience at Georgetown University and director of Georgetown's Brain and Language Lab.

The researchers conducted an experiment to measure the attention and executive function of 702 participants between the ages of 58 and 98.

"They focused on these ages since this is when cognition often changes the most during aging," the medical center noted in its news release.

The researchers displayed three arrows on a computer screen and asked participants to press a button corresponding to the direction the middle arrow was pointing as quickly as possible. Signals were also placed on the screen to suggest where the arrows would be before they were actually displayed.

What the researchers found is that older people were less prepared to respond to the next signals. Conversely, older participants were better able to concentrate on the current situation.

Furthermore, older people were better at compensating for contradictory signals and events that distracted their attention from the computer screen. The study suggests that this ability improves at least until the mid-to-late 70s.

In this study, the researchers examined the alerting, orienting, and executive (or inhibitory) networks postulated by Michael Posner in his theory of attention in 1990.

"Alerting is characterized by a state of enhanced vigilance and preparedness in order to respond to incoming information. Orienting involves shifting brain resources to a particular location in space. The executive network inhibits distracting or conflicting information, allowing us to focus on what's important," the medical center said.

"We use all three processes constantly," said João Veríssimo, assistant professor at the University of Lisbon and lead researcher in the study.

"For example, when you are driving a car, alerting is your increased preparedness when you approach an intersection. Orienting occurs when you shift your attention to an unexpected movement, such as a pedestrian. And executive function allows you to inhibit distractions such as birds or billboards so you can stay focused on driving."

"The study found that only alerting abilities declined with age. In contrast, both orienting and executive inhibition actually improved," the medical center said.

Why would that be?

"The researchers hypothesize that because orienting and inhibition are simply skills that allow people to selectively attend to objects, these skills can improve with lifelong practice," the medical center said.

"In contrast, they believe that alerting declines because this basic state of vigilance and preparedness cannot improve with practice."

The researchers said the benefits from such practice can be considerable enough to compensate for neural decline. But the alerting function is a basic brain state that can't be improved by practice, which makes it more likely to decline over time.

The researchers said they hope that these findings about the orienting and executive functions — which serve as the basis for so much human behavior — "may also lead to clinical improvements, including for patients with aging disorders such as Alzheimer's disease."

By Kwak No-pil, senior staff writer

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