Sweet Memories: Do you recall what you had for dessert at your last dinner party? I’m sure you would remember the hippocampus cookies (left image)! The hippocampus (right image) is the part of our brain responsible for episodic memory, the kind associated with a great dinner surrounded by family or friends. It enables you to “play back” the memories, until eventually the memory becomes ingrained in the cortex.
• The hippocampus is also important for spatial memory: in one study, British researchers asked taxi drivers to imagine their routes through London while their brain activity was scanned by positron emission tomography (PET scan). This task specifically activated the right lobe of the hippocampus. There are other types of memory that do not involve the hippocampus: semantic memory, for general knowledge (frontal and temporal cortex), emotional memory such as fear (amygdala), and procedural memory, such as knowing how to ride a bike (cerebellum, motor cortex).
• In Alzheimer’s disease, the hippocampus is the first, and most severely, affected part of the brain. That’s why new memories are the first to go: Where did I put the car keys? Why is there no mail today (because you just brought it in).
• The distinct curves of the hippocampus region of the vertebrate brain has been likened to a sea horse (genus Hippocampus) from Greek mythology, and the horns of the ram Amun, in Egyptian mythology. The latter name is the basis for four regions, designated CA1-4, after Cornu Ammonis or the horns of Amun.
Remember to tag your posts #scienceeveryday when it’s not ScienceSunday 🙂