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Parkinson's May Begin in Gut and Spread to the Brain Via the Vagus Nerve - Neuroscience News

The research has presented strong evidence that Parkinson’s disease begins in the gastrointestinal tract and spreads via the vagus nerve to the brain. Many patients have also suffered from gastrointestinal symptoms before the Parkinson’s diagnosis is made. “Patients with Parkinson’s disease are often constipated many years before they receive the diagnosis, which may be an early marker of the link between neurologic and gastroenterologic pathology related to the vagus nerve ,” says Elisabeth Svensson.