Parents take note: if you want your kids to grow bigger brains, think twice about letting schools cut recess or skimp on physical education.
Animal and human studies have long shown that exercise increases neurogenesis, especially in memory- and learning-related areas of the brain.1, 2 More recently, research on human adolescents has not only confirmed these findings, but highlighted the importance of physical activity for children.
Art Kramer and several colleagues at the University of Illinois published two studies this year that demonstrated correlations not only between exercise and improved cognitive abilities, but exercise and actual brain growth, as well. In the first study3, scientists recruited 9-and-10 year-old children who were either very physically fit or not fit at all. They then asked both groups to complete computer tasks measuring how well the children could filter out extraneous information and attend to relevant cues. Finally, they used MRI to measure the volume of certain structures in the children’s brains. What they found was that not only did the more physically fit children score better on the computer tasks, but their basal ganglia—a brain structure responsible for maintaining attention and coordinating actions and thoughts with precision—was also significantly larger.
In the second study4, another group of high- and low- fitness 9- and 10-year olds was recruited. This time the children were tested on their complex memory, for which brain activity has been linked the hippocampus. As may have been predicted from the results of the first experiment, MRI brain scans showed that the fitter children possessed larger hippocampi.
So if exercise promotes neurogenesis, what else might help grow your brain?
Alcohol. In moderation, alcohol may actually increase brain cells. Mice that consumed moderate amounts of ethanol experienced cell proliferation in their dentate gyrus, a part of the hippocampus.5
Chocolate. Cocoa, the major ingredient in chocolate, contains a antioxidant called epicatechin, which has been shown to improve spatial memory in mice.6
Marijuana. A controversial study found that stimulating rats’ brain receptors for marijuana increased neurogenesis.7 Gary Wenk at Ohio State University has continued in this line of research, exploring medicinal use of THC (the main psychoactive substance in marijuana) to prevent Alzheimer’s disease. However, the subject remains controversial, as a recent review in Drug and Alcohol Review will attest.8
1. van Praag, H. (1999). Running enhances neurogenesis, learning, and long-term potentiation in mice Proceedings of the National Academy of Sciences, 96 (23), 13427-13431 DOI: 10.1073/pnas.96.23.13427
2. Praag, H. (2008). Neurogenesis and Exercise: Past and Future Directions NeuroMolecular Medicine, 10 (2), 128-140 DOI: 10.1007/s12017-008-8028-z
3. Chaddock, L., Erickson, K., Prakash, R., VanPatter, M., Voss, M., Pontifex, M., Raine, L., Hillman, C., & Kramer, A. (2010). Basal Ganglia Volume Is Associated with Aerobic Fitness in Preadolescent Children Developmental Neuroscience, 32 (3), 249-256 DOI: 10.1159/000316648
4. Chaddock, L., Erickson, K., Prakash, R., Kim, J., Voss, M., VanPatter, M., Pontifex, M., Raine, L., Konkel, A., & Hillman, C. (2010). A neuroimaging investigation of the association between aerobic fitness, hippocampal volume, and memory performance in preadolescent children Brain Research, 1358, 172-183 DOI: 10.1016/j.brainres.2010.08.049
5. Åberg, E., Hofstetter, C., Olson, L., & Brené, S. (2005). Moderate ethanol consumption increases hippocampal cell proliferation and neurogenesis in the adult mouse The International Journal of Neuropsychopharmacology, 8 (04) DOI: 10.1017/S1461145705005286
6. van Praag, H., Lucero, M., Yeo, G., Stecker, K., Heivand, N., Zhao, C., Yip, E., Afanador, M., Schroeter, H., Hammerstone, J., & Gage, F. (2007). Plant-Derived Flavanol (-)Epicatechin Enhances Angiogenesis and Retention of Spatial Memory in Mice Journal of Neuroscience, 27 (22), 5869-5878 DOI: 10.1523/JNEUROSCI.0914-07.2007
7. Jiang, W. (2005). Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects Journal of Clinical Investigation, 115 (11), 3104-3116 DOI: 10.1172/JCI25509
8. DOWNER, E., & CAMPBELL, V. (2009). Phytocannabinoids, CNS cells and development: A dead issue? Drug and Alcohol Review, 29 (1), 91-98 DOI: 10.1111/j.1465-3362.2009.00102.x