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.
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.