The vagus nerve innervates much of our viscera – in fact all of our internal organs with the notable exception of the adrenal glands. It supplies parasympathetic fibers to these organs, meaning that the vagus nerve is a “rest and digest” nerve, not a fight or flight nerve. Van der Kolk on Darwin’s work, “the heart, guts and brain communicate intimately via a nerve” – the pneumogastric or vagus nerve – “the critical nerve in the expression and management of emotions in both humans and animals…. When the mind is strongly excited it instantly affects the state of the viscera.” This is, of course, why our guts react strongly to our emotional state.
https://healingfromthefreeze.wordpress.com/2011/08/18/the-vagus-nerve-and-the-difficulty-with-mindfulness/ (This link will take you out of this NEUniversity website)
Resource submitted by Bascha Meier.