The vagus nerve plays a role in (amongst other things) controlling the pulse. The vagus reflex is a reaction which can reduce the pulse rate. Intentionally inducing a vagus reflex is sometimes used to treat tachycardia (racing pulse). The following stimuli may produce the vagus reflex:
- tensing the lower abdomen (similar to straining at stool)
- gentle pressure on the closed eyes
- a gulp of ice-cold water
- splashing ice-cold water on the face
- immersing the arms in ice-cold water
- finger stuck down the throat
- the insertion of an IV needle
- cough or sneeze (involuntary or autonomic works best)
- holding breath (after exhaling) - see Valsalva manoeuvre
- insertion of an object into the uterus such as an IUD
Famous quotes containing the word reflex:
“As a medium of exchange,... worrying regulates intimacy, and it is often an appropriate response to ordinary demands that begin to feel excessive. But from a modernized Freudian view, worrying—as a reflex response to demand—never puts the self or the objects of its interest into question, and that is precisely its function in psychic life. It domesticates self-doubt.”
—Adam Phillips, British child psychoanalyst. “Worrying and Its Discontents,” in On Kissing, Tickling, and Being Bored, p. 58, Harvard University Press (1993)