How deep does emotion go? When fear trumps reason, pop psychologists tell us it's the older, reptilian part of our brain taking over. But what brain circuits are really responsible, and how are they wired up?
To answer this very big question, a Caltech neurobiologist, a computer scientist, and a bioengineer have started very small—with Drosophila melanogaster, otherwise known as the common fruit fly.
Written by
Douglas Smith
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A lunging fly looks angry, but the "emotion" is a hard-wired reflex. Now a computer-vision system that watches flies and can figure out what they're doing is helping biologists trace those wires— and might one day be able to read human emotions.
Credit: Eric Hoopfer
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