You’re reading these words because you have a brain in your head. But did you know you also have a brain in your butt?
OK, not a literal brain — more of an autonomous matrix of millions of neurons that can, somehow, control intestinal muscle movements without any help from your central nervous system. And these neurons don’t actually live in your butt, but they do live in your colon, or large intestine — that tube-like organ that connects the small intestine to the rectum and shepherds what remains of the food you ate through the final leg of the digestive tract.
Scientists call this site of colon intelligence your enteric nervous system, and because it can function without instructions from the brain or spine, some scientists like to call it your “second brain.” How smart is this autonomous, intestinal brain? Scientists don’t know for sure yet. But according to a new study in mice, published May 29 in the journal JNeurosci, the answer might be pretty smart for an intestine.