Did you realise you had two brains? The enteric nervous system, which has control over the gut, is awash with neurotransmitters and surprisingly independent from the central nervous system. It is only recently that the importance of this ‘second brain’ has been acknowledged and its complexities have begun to be uncovered.
This article from the International Herald Tribune explains some recent findings including the theory that stressful experiences early in life may cause irritable bowel syndrome.
International Herald Tribune