The enteric nervous system that regulates our gut is often called the body’s “second brain.”

on the brain logo.Although it can’t compose poetry or solve equations, this extensive network uses the same chemicals and cells as the brain to help us digest and to alert the brain when something is amiss. Gut and brain are in constant communication.

“There is immense crosstalk between these two large nerve centers,” says Braden Kuo, MD, MMSc ’04, co-executive director of the Center for Neurointestinal Health at Massachusetts General Hospital (MGH) and assistant professor of medicine at Harvard Medical School. “This crosstalk affects how we feel and perceive gastrointestinal (GI) symptoms and impacts our quality of life.”

Normally, when we see something tasty, the brain signals the gut to prepare for incoming food. When we feel anxious or stressed, we might experience these as abdominal pain, diarrhea, nausea, or “butterflies.” Messages travel from gut to brain, too. This helps explain why, when we eat something that makes us sick, we instinctively avoid the food and even the place we found it.

These everyday activities can go awry when gut nerves are damaged or malfunction. The Center for Neurointestinal Health treats patients with life-altering conditions such as chronic constipation, extreme bloating, and irritable bowel syndrome (IBS). Center physician-scientists also contribute to the exciting basic, clinical, and translational research happening across HMS to understand the gut-brain connection.