The Incredible Shrinking Brain
Need more motivation to get moving? How about this: Exercise could help keep you brain from shrinking. Scientists have known for years that older people often experience a curious decrease in brain volume. And this is no small thing. Shrinking brains are cause for concern. Loss of brain mass is usually accompanied by cognitive decline; a gradual loss of memory and thinking capacity. Brain studies among young and old subjects suggest that much of this age-associated loss in brain mass involves the loss of white matter.
Although we usually think of “gray matter” when we think about, well, thinking, we now know that white matter is not the passive tissue we once believed it to be. In fact, recent research shows that it’s nearly as important for cognition as gray matter. White matter plays a crucial role in learning, for instance, and allows for coordination among different regions of the brain.
Advances in modern imaging technology allow doctors to assess these changes in brain activity in real time, among healthy, living people. Scottish researchers wondered if staying physically active in old age might help prevent the loss of brain tissue, while preserving cognitive function. Lucky for them, there’s a group of people in Great Britain who are enrolled in an aging study. These folks hit 70 years of age in 2006, and investigators from the University of Edinburgh documented how physically active they were. Three years later, the researchers performed brain scans and determined that people who were more physically active experienced significantly less white matter loss, and less brain atrophy than their peers who were less active. Gives new meaning to the phrase ‘use it or lose it,’ don’t you think?
Fields RD. White Matter Matters Scientific American 298, 54 - 61 (2008) doi:10.1038/scientificamerican0308-54
Gow AJ, Bastin ME, Muñoz Maniega S, Valdés Hernández MC, Morris Z, Murray C, et al. Neuroprotective lifestyles and the aging brain: activity, atrophy, and white matter integrity. Neurology. 2012 Oct 23;79(17):1802-8. doi: 10.1212/WNL.0b013e3182703fd2.