Enteric nervous systems are embedded directly in the lining of the human gastrointestinal tract, consisting of over one hundred million neurons that can operate entirely independently from the brain in your head.

A closer look

Enteric nervous systems are embedded directly in the lining of the human gastrointestinal tract, consisting of over one hundred million neurons that can operate entirely independently from the brain in your head. This intricate network of neurotransmitters does not write poetry or solve algebra, but it completely controls digestion and strongly influences your emotional state by producing ninety percent of your body's serotonin. Your gut literally has a mind of its own, which explains why being stressed makes you nauseous and being hungry turns you into an absolute monster. We like to pretend we are highly rational creatures driven by logic, but our emotional stability is entirely dependent on an irritable tube of intestines!