Hippocampus
A structure in the brain essential to memory formation, named after the hippocampus, the half-horse half-fish creature that pulled Poseidon's chariot, because of its seahorse-like shape
The Meaning of Hippocampus
The hippocampus is a curved structure deep within the temporal lobe of the brain that plays a critical role in the formation of new memories and spatial navigation. It was named by the sixteenth-century anatomist Julius Caesar Aranzi, who noted its resemblance to a seahorse — the hippocampus in Greek (hippos = horse, kampos = sea monster). In Greek mythology, hippocampi were creatures with the front half of a horse and the tail of a fish or dolphin that pulled Poseidon's chariot across the sea. They appear frequently in Greek and Roman art, ridden by Nereids and Tritons through ocean waves. The anatomical hippocampus became one of the most studied structures in neuroscience after the famous case of patient Henry Molaison in 1953, whose hippocampi were surgically removed to treat severe epilepsy. The surgery stopped his seizures but left him unable to form any new long-term memories for the remaining fifty-five years of his life. This case proved definitively that the hippocampus is essential for converting short-term experiences into lasting memories. The mythological sea-horses of Poseidon thus gave their name to the brain structure that creates our personal histories.
Parents
None recorded
Symbols
Fun Fact
The discovery that removing this brain structure destroyed the ability to form new memories came from a single patient who lived without long-term memory for fifty-five years
Words We Inherited
English words and phrases that trace back to this myth. See our full guide to English words from Greek mythology.
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Hippocampus
🐉 creaturesea creatures
A horse-bodied sea creature with a fish or serpent tail that pulled Poseidon's chariot
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💭 conceptMythology and architecture
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