[Physiology of the Vagus Nerve: Basic Medical Research from the Past to the Present].

The vagus nerve, which is the 10th cranial nerve, exits from the medulla and distributes widely to the visceral organs. Although it contains the motor, somatic, and sympathetic nerves, the main component is the parasympathetic nerve, which acts as the core of homeostasis. The vagal efferent regulates the cardiac muscle, striated muscle and glands, while the vagal afferent sends the information from the visceral organs to the brain. The vagus nerve is also responsible for the gut-brain axis.