One of the most multifunctional nerves in the body, it is the longest cranial nerve and contains both afferent and efferent fibbers. The only cranial nerve to enter the trunk, it passes through the neck, thorax and abdomen to supply sensory information to part of the ear, tongue, larynx and pharynx, and efferent discharges to the vocal cords, as well as to the abdominal and thoracic viscera (to control gastrointestinal peristalsis). It also controls much of the activity of the parasympathetic nervous system, in particular slowing down heart rate by way of the sino-atrial node. Via the recurrent laryngeal nerve, it is crucial to the sensorimotor control of speech and swallowing, the former with regard to variations in patterns of intonation associated with emotion (e.g., crying). It not only controls smooth muscle, but also a few skeletal muscles (e.g., laryngeal muscles).
See Cranial nerves, Crying, Larynx, Neurotransmitters, Parasympathetic nervous system (PNS), Pharynx, Smooth (or involuntary) muscle, Striated (or striped or voluntary) muscle