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How to Beef Up Your Hippocampus

by Katherine J. Dickinson

Having a brawny hippocampus might not get you a whole lot of wolf-whistles or cat-calls on the beach, but it can improve your memory. The good news is that if you're physically fit, you are already on your way to being mentally fit. Aerobic exercise not only gets your body in shape, but, according to recent research, it can help enlarge your hippocampus.

That's like two workouts in one!

The hippocampus is a region of the brain that deals with learning and memory, and also with spatial navigation. It is considered part of the limbic system--the headquarters for emotion. While the hippocampus' role in memory is yes to be fully understood, it seems that the region may play a role in forming new memories.

Hippocampus_and_seahorse.JPG
The hippocampus compared to a seahorse. See any resemblance? By Professor Laszlo Seress (Retrieved via email from the creator.) 

One recent study used magnetic resonance imaging (MRI) to show that physical fitness is related to hippocampal volume in nine and ten-year-old children. The results showed that the hippocampus of fit children was about 12 percent bigger than non-fit children. Not only that, but the fitter kids also used their burly hippocampus to perform better on memory tasks.    Another study showed that the same is true for the opposite end of the generation spectrum. A group of older adults aged 55 to 80 participated in an aerobic workout program for one year, while another group simply engaged in stretching. After the year was up, researchers took a look at the subjects' brains and found that hippocampus of the active adults had indeed gotten bigger. Although the growth was small -- 2.12 percent in the left hippocampus and 1.97 percent in the right hippocampus -- the study was important because it showed that the hippocampus can still grow and change as we get older.

A lot of what we know about the hippocampus comes from studying a man named Henry Molaison who had the hippocampus on both sides of his brain surgically removed in an effort to control seizures. In a magnificent and surprisingly personal essay that was published in Esquire and included in in Best American Science and Nature Writing 2011, Luke Dittrich describes how the lobotomy affected Henry's behavior and what researchers found when they dissected his brain after he died.

I myself first became interested in the hippocamus while I was doing research one summer. We were studying the affects of bisphenol A (BPA) in a couple specific brain regions. Our study required samples of rat hippocampal tissue, so at one point I remember inspecting a little plastic container of clear liquid with a freshly-collected hippocampus inside.

I recalled that some of the first researchers of the hippocampus thought that it resembled a seahorse, so they named it after the Greek word for that sea creature. Sure enough, the structure I was looking at had a crescent shape to it, but I did not think of a seahorse. It reminded me more of candy -- specifically banana Runts.

Maybe that's an indication that I need to stop scarfing down Runts in front of the TV and head to the gym for a little aerobic exercise.

bananarama_bulk.jpgSee? Exactly like a hippocampus....only yummier.

Katherine Dickinson is a freelance writer from Minnesota.