A short burst of exercise enhances the consolidation of memories in both healthy older adults and those with mild cognitive impairment, according to new research.
According to scientists with the University of California Irvine’s Center for the Neurobiology of Learning & Memory, most research has focused on the benefits of a long-term exercise program. But they decided to examine the immediate effects of a brief bout of exercise on memory.
In the study, post-doctoral researcher Dr. Sabrina Segal and colleagues had people between the ages of 50 and 85 with and without memory deficits view pleasant images, such as photos of nature and animals. Then subjects exercised on a stationary bicycle for six minutes at 70 percent of their maximum capacity.
An hour later, the participants were given a surprise test on the images. Results showed a striking enhancement of memory in both the healthy and cognitively impaired adults, compared with people who did not ride the bike.
“We found that a single, short instance of moderately intense exercise particularly improved memory in individuals with memory deficits,” Segal said. “Because of its implications and the need to better understand the mechanism by which exercise may enhance memory, we’re following up this study with an investigation of potential underlying biological factors.”
She said she believes the improved memory may be related to the exercise-induced release of norepinephrine, a chemical messenger in the brain known to play a role in memory modulation.
This hypothesis is based on previous work demonstrating that increasing norepinephrine through pharmacological manipulation sharpens memory and that blocking norepinephrine impairs memory, she explained.
In the latest research, the scientists discovered that levels of salivary alpha amylase, a biomarker that reflects norepinephrine activity in the brain, significantly increased in participants after exercise.
This correlation was especially strong in people with memory impairment, the researchers noted.
“The current findings offer a natural and relatively safe alternative to pharmacological interventions for memory enhancement in healthy older individuals, as well as those who suffer from cognitive deficits,” Segal noted. “With a growing population of the aged, the need for improvement of quality of life and prevention of mental decline is more important than ever before.”
The study’s co-authors were Carl Cotman and Lawrence Cahill.
Study results were published in the Journal of Alzheimer’s Disease.
Source: University of California, Irvine