Researchers at Boston University used electrostimulation to temporarily restore the working memory of 70-year-olds to function like that of people nearly 50 years younger. Their study appeared in this month’s issue of Nature Neuroscience.
Working memory allows the brain to briefly hold new information needed for processing. It helps humans plan, comprehend, reason, and solve problems. The brain’s capacity for this kind of processing begins to decline when people are in their late 20s or early 30s. By the time they reach their 60s and 70s, most experience noticeable changes.
In the study, the researchers asked a group of people in their 20s and a group in their 60s and 70s to perform a series of memory tasks. Initially, the young adults scored much higher than the older subjects. But after the scientists delivered 25 minutes of mild electrical stimulation to the brains of the older subjects through electrodes on their scalps, the differences between the two groups disappeared.
The researchers opened up brain pathways that tend to go awry with age by tailoring the electrical stimulation to the specific rhythms of each individual’s brain circuits. The memory improvement lasted to the end of the 50-minute testing time, at which point the researchers terminated the experiment.
“These findings are important because they not only give us new insights into the brain basis for age-related working memory decline, but they also show us that the negative age-related changes are not unchangeable,” lead researcher Robert Reinhart told Live Science. —J.B.