“Gut Sense” is Hardwired, not Hormonal - Neural Superhighway Conveys Messages From Gut to Brain. Using a fluorescence rabies virus, researchers traced a signal from the intestines to the brainstem of mice. The signal crossed a single synapse in under 100 milliseconds, faster than the blink of an eye

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“Gut Sense” is Hardwired, not Hormonal - Neural Superhighway Conveys Messages From Gut to Brain. Using a fluorescence rabies virus, researchers traced a signal from the intestines to the brainstem of mice. The signal crossed a single synapse in under 100 milliseconds, faster than the blink of an eye