Multiple studies in the past have linked better fitness with better neurological and cognitive function. For example, a 2014 Harvard study found that regular exercise causes changes in the brain that improve memory and enhances thinking skills. Exercise can also reduce inflammation, stimulate new brain growth factors, and increase blood flow to the brain.
A new study from the National Institutes of Biomedical Imaging and Bioengineering has discovered a new cognitive benefit of exercise: greater elasticity and firmness of the hippocampus, which in turn leads to better memory.
The study examined 51 healthy adults between the ages of 18 and 35. The participants underwent an aerobic test to determine their overall fitness levels, as well as a memory test. They were also subjected to an MRE to measure their hippocampus’ elasticity.
The results were clear: the higher the fitness level of the adult, the more elastic their hippocampus. Greater elasticity of the brain tissue in this region has been associated with better memory, as was proven by the higher performance on the memory tests. The fitter the bodies of the adults being tested, the fitter their brains as well.
Interestingly enough, the fitness level of the adults had nothing to do with the size of their hippocampus. According to the study, “atrophy and reduced size of the hippocampus” were common among “cognitively declining seniors and developmentally delayed children.”
However, despite this size-function correlation, the study found that “although we see an increase in memory in more aerobically fit individuals, we did not see differences in hippocampal size.”
Clearly, the size of the hippocampus isn’t the only marker to help researchers measure cognitive function, specifically memory in this case. The fitness level of the adults had no effect on the size of this part of the brain, yet the fitter adults performed better on memory tests. The elasticity of the brain tissue appeared to have a greater effect on cognitive performance than size.
Reference:
1. Schwarb H, Johnson CL, Daugherty AM, Hillman CH, Kramer AF, Cohen NJ, Barbey AK. “Aerobic fitness, hippocampal viscoelasticity, and relational memory performance,” Neuroimage. 2017 Jun;153:179-188.
