Exercise activates memory neural networks in older adults: study

Recent findings suggest that when it comes to older adults, just one session of exercise can increase activation in the brain circuits associated with memory - including the hippocampus - which shrinks with age and is the brain region attacked first in Alzheimer's disease.

"While it has been shown that regular exercise can increase the volume of the hippocampus, our study provides new information that acute exercise has the ability to impact this important brain region," said Carson Smith, lead author of the study.

The study was published in the Journal of the International Neuropsychological Society.

The team of researchers measured the brain activity (using fMRI) of healthy participants ages 55-85 who were asked to perform a memory task that involves identifying famous names and non-famous ones.

The action of remembering famous names activates a neural network related to semantic memory, which is known to deteriorate over time with memory loss.

This test was conducted 30 minutes after a session of moderately intense exercise (70% of max effort) on an exercise bike and on a separate day after a period of rest.

Participants' brain activation while correctly remembering names was significantly greater in four brain cortical regions (including the middle frontal gyrus, inferior temporal gryus, middle temporal gyrus, and fusiform gyrus) after exercise compared to after rest. The increased activation of the hippocampus was also seen on both sides of the brain.

"Just like a muscle adapts to repeated use, single sessions of exercise may flex cognitive neural networks in ways that promote adaptations over time and lend to increased network integrity and function and allow more efficient access to memories," Smith explained.