Vagi

Vagi is the Latin plural form of the noun vagus and is sometimes used in anatomical texts to refer to the vagus nerves. In modern English, the standard plural is “vagus nerves” or “the vagus nerves.” The form “vagi” appears mainly in historical or Latin-language contexts and is uncommon in contemporary clinical writing.

The vagus nerves are the tenth pair of cranial nerves (CN X). Each nerve arises from the medulla oblongata and travels through the neck into the thorax and abdomen. They contain motor, sensory, and parasympathetic fibers and give rise to a network of branches that innervate the pharynx, larynx, thoracic viscera, and much of the gastrointestinal tract. The left and right vagus nerves follow slightly different courses, with notable branches including the recurrent laryngeal nerves.

Functions of the vagus nerves include modulation of heart rate and cardiac conduction, bronchoconstriction and regulation of airway secretions, and stimulation of digestive secretions and gastrointestinal motility. They also convey visceral sensory information from thoracic and abdominal organs and provide motor control for muscles involved in swallowing and voice production. Through their sensory and autonomic roles, the vagus nerves participate in reflexes such as coughing, gagging, and swallowing.

Clinical relevance centers on the importance of intact vagal function. Vagal injury or dysfunction can affect heart rate, digestion, voice, and swallowing. Therapeutic uses related to vagal activity include maneuvers that increase vagal tone to affect heart rhythm and vagus nerve stimulation for epilepsy or treatment-resistant depression.