Vagus Nerve
/vāges nerv/ noun
Latin word for "wandering"
10th cranial nerve & longest nerve in the body
Main nerve of the parasympathetic nervous system
It connects our brain to our body
- major component of the parasympathetic nervous system
- vagus nerve is family of nerves that wander through out the body
- begins in the brainstem, it is a nerve that comes off the brain
it goes directly to the heart and other visceral organ
it is involved in the regulation of physiological processes in major organs but most important in the heart and gut
top down bottom up function (organs send messages to the brain, brain sends messages to the organs)
1. the dorsal vagal influences organs below the diaphragm
2. the ventral vagal influences organs above the diaphragm
through the dorsal and ventral vagal nerve, messages are sent in 2 directions
the vagus nerve is a bidirectional highway: sensory information from our body travels to the brain and motor information from the brain goes to the body.
the two vagal pathways represent the evolution of the autonomic nervous system
- the oldest is the dorsal branch (our reptilian ancestors) and the newest is the ventral vagal (uniquely mammalian)
The ventral vagal pathway travels from the heartland is connected through pathways to the face and head: regulating how you see hear speak express emotions with your face, turn and tilt your head
this system is constantly sending and receiving information about yourself and fathering information form others.
this social engagement system sends signals either inviting or discouraging connection. it looks for warning or welcoming.
Evolution and history of the vagus nerve
oldest primal one: below our diaphragm, we share this with reptiles, even fish
evolutionary newer one: evolved with mammals for one another to regulate and survive