While it has long been held that all cognitive abilities decline with age, new research shows that some of these abilities can actually improve over a lifetime.
The findings, published in Nature Human Behavior, show that two key brain functions, focusing and attending to new information, can in fact improve in older individuals. These functions underlie key aspects of cognition including memory, decision making, and self-control, and even navigation, math, language and reading.
“These results are amazing, and have important consequences for how we should view aging,” said senior investigator, Michael T Ullman, PhD, a professor in the Department of Neuroscience and director of Georgetown’s Brain and Language Lab.
“People have widely assumed that attention and executive functions decline with age, despite intriguing hints from some smaller-scale studies that raised questions about these assumptions,” he said. “But the results from our large study indicate that critical elements of these abilities actually improve during aging, likely because we simply practice these skills throughout our life.”
“This is all the more important because of the rapidly aging population, both in the U.S. and around the world,” Ullman said, adding that with further research, it may be possible to deliberately improve these skills to protect against cognitive decline.
The research team explored three separate components of attention and executive function in a group of 702 participants aged 58 to 98. This age range was chosen since this is when cognition often changes the most during aging.
The components they studied are the brain networks involved in alerting, orienting and executive inhibition. Each has different characteristics and relies on different brain areas and different neurochemicals and genes. Therefore, Ullman and Veríssimo reasoned, the networks may also show different aging patterns.
Alerting is characterised by a state of enhanced vigilance and preparedness, while 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.
“We use all three processes constantly,” Veríssimo explains. “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.”
Surprisingly, only alerting abilities declined with age while both orienting and executive inhibition actually improved.
The researchers hypothesis is that because orienting and inhibition are simply skills that allow selective attention, these skills can improve with lifelong practice. Ullman and Veríssimo suggest that these gains can be large enough to outweigh the underlying neural declines. Alerting declines, they believe, because this basic state of vigilance and preparedness cannot improve with practice.
“Because of the relatively large number of participants, and because we ruled out numerous alternative explanations, the findings should be reliable and so may apply quite broadly,” Veríssimo said, adding that “because orienting and inhibitory skills underlie numerous behaviors, the results have wide-ranging implications.”
“The findings not only change our view of how aging affects the mind, but may also lead to clinical improvements, including for patients with aging disorders such as Alzheimer’s disease,” said Ullman.
