The gag reflex is a reflex contraction of the back of the throat that prevents something from entering the throat except as part of normal swallowing. This helps prevent choking. It is also known as a pharyngeal reflex. A reflex action or reflex is a biological control system linking stimulus to response and mediated by a reflex arc. ... Swallowing, known scientifically as deglutition, is the reflex in the human body that makes something pass from the mouth, to the pharynx, into the esophagus, with the shutting of the epiglottis. ... For choking meaning compression of the neck, see Strangling. ...

Touching the soft palate evokes a strong gag reflex in most people, although people can train themselves to resist the gag reflex, for example as part of the act of sword swallowing. The gag reflex can also be used to induce vomiting. The soft palate, or velum, is the soft tissue comprising the back of the roof of the mouth. ... Sword swallowing is a dangerous performance art, in which the performer inserts a sword into his mouth and down his esophagus towards his stomach. ... Vomiting (also throwing up or emesis) is the forceful expulsion of the contents of ones stomach through the mouth and sometimes the nose. ...

The afferent limb of the reflex is supplied by the glossopharyngeal nerve (cranial nerve IX), which inputs to the nucleus solitarius, and the efferent limb is supplied by the vagus nerve (cranial nerve X) from the nucleus ambiguus. Absence of the gag reflex is a symptom of a number of severe medical conditions, such as damage to the glossopharyngeal nerve, or the vagus nerve. The glossopharyngeal nerve is the ninth of twelve cranial nerves. ... The solitary nucleus and tract are structures in the brainstem that carry and receive visceral sensation and taste from the facial (VII), glossopharyngeal (IX), vagus (X) cranial nerves, as well as the cranial part of the accessory nerve (XI). ... The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the abdomen. ... The nucleus ambiguus (literally ambiguous nucleus) is a region of histologically disparate cells located just dorsal (posterior) to the inferior olivary nucleus in the lateral portion of the upper (rostral) medulla. ...

External links

• How to deal with an easily stimulated gag reflex

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Also a Call of Duty 2 online clan, playing S&D and CTF. tag .:{gR}- Image File history File links Uppergi. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and...