Researchers have shown that people with good endurance have better memory. Using magnetic resonance elastography (MRE), they discovered that cardiovascular training increases the elasticity of the hippocampus, an area associated with memory. This insight could contribute to preventing the early development of brain diseases.
Healthy Hippocampus and Memory
Cardiovascular fitness has long been associated with better memory. Reduced cognitive function in the elderly, as well as children with developmental delays, has previously been linked to a smaller hippocampus. Previous research on the relationship between memory and fitness showed a positive correlation but strangely did not show a correlation with the size of the hippocampus. However, size is not the only indication of hippocampal health. Researchers from the universities of Illinois, Delaware, and Northeastern in Boston therefore decided to use MRE to measure other properties of the hippocampus. Using this method, they discovered that the hippocampus of fit individuals with better memory was more elastic, another indication of hippocampal quality than size.MRE is a technique that has been used in organs like the liver, where it can assess the tissue stiffness and offers a reliable, non-invasive method for diagnosing hepatic fibrosis Guoying Liu, Ph.D. Director of the NIBIB program on Magnetic Resonance Imaging. “This study now demonstrates the tremendous potential for MRE to provide new quantitative biomarkers for assessing brain health as it relates to physical fitness. This is particularly significant given the rise in dementia and Alzheimer’s disease occurring in the U.S. and worldwide. Guoying Liu, NIBIB program on Magnetic Resonance ImagingThe researchers explain that MRE can provide a much better indication of the microstructure of the hippocampus, the structural integrity of the entire tissue. The information is obtained by bouncing the organ, so to speak, and recording the reaction. A pillow under the head causes vibrations that travel through the hippocampus. The MRE instrumentation measures how these vibrations change as they travel through the brain, and based on the changes in the vibrations, they can measure the consistency and properties of the tissue very accurately. Is it hard and stiff or rather firm and elastic? The tissue of a healthy hippocampus should, like a firm pillow, return to its shape after being pressed with a finger.
Cardio and Memory
The researchers studied 51 healthy adults; 25 men and 26 women between the ages of 18 and 35. They measured how the participants scored on a memory test and assessed their level of physical fitness. They then measured the elasticity of the hippocampus using MRE. They found that participants with higher levels of cardiovascular fitness had greater hippocampal elasticity and scored higher on the memory test. A good reason, therefore, not to forget your cardio.References
- Hillary Schwarb, Curtis L. Johnson, Ana M. Daugherty, Charles H. Hillman, Arthur F. Kramer, Neal J. Cohen, Aron K. Barbey. Aerobic fitness, hippocampal viscoelasticity, and relational memory performance. NeuroImage, 2017; 153: 179 DOI: 10.1016/j.neuroimage.2017.03.061
