Sneeze
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For other uses, see Sneeze (disambiguation).
A sneeze (or sternutation) is a semi-autonomous, convulsive expulsion of air from the lungs. It occurs when a particle (or sufficient particles) passes through the nasal hairs and reaches the nasal mucosa. This triggers the production of histamines, which reach the nerve cells in the nose, which then send a signal to the brain to initiate the sneeze, which relates the initial signal and creates a large opening of the nasal cavity, resulting in a powerful release of air and bioparticles. The reason behind the powerful nature of a sneeze is its involvement of not simply the nose and mouth, but numerous organs of the upper body - it is a reflectory response that involves the muscles of the face, throat, and chest. Sneezes are capable of spreading disease through the potentially infectious aerosol droplets that they can expel, which generally range from 0.5 to 5 µm in diameter. About 40,000 such droplets can be produced by a single sneeze.[1] The speed of this release has been the source of much speculation, with the most conservative estimates placing it around 150 kilometers/hour (42 meters/second) or roughly 95 mph (135 feet/second), and the highest estimates -such as the JFK Health World Museum in Barrington, Illinois- which propose a speed as fast as 85% of the speed of sound, corresponding to approximately 1045 kilometers per hour (290 meters/second) or roughly 650 mph (950 feet/second). In certain individuals, sneezing can also be triggered by sudden exposure to bright light, particularly that of the Sun, as well as the customary irritation of the mucosa – a response known as the photic sneeze reflex. A somewhat unusual alternative trigger of uncontrollable bursts of sneezing in particular individuals is the fullness of the stomach immediately after a large meal. This is known as snatiation and is regarded a medical disorder passed along genetically as an autosomal dominant trait. In recent years, studies have shown[citation needed]that stifling or holding back sneezes can cause damage to the sinuses as well as to the inner ear and brain cells. This is due to the back-flow of the significant air pressure created during a sneeze, results of which could be very painful. Possible consequences include tinnitus, reduced high-frequency hearing, and in extreme cases, rupturing of the ear drum. Safer alternatives have been proposed to stifle sneezes, including methods involving prolonged deep exhalation immediately preceding a sneeze, which in turn empties the lungs, rendering the body unable to expel the necessary amount of air required for an average sternutation.
OnomatopoeiaSome common English onomatopoeias for the sneeze sound are achoo, atchoo, achew, and atisshoo, with the first syllable corresponding to the sudden intake of air, and the second to the sound of the sneeze. A similar linguistic approach has been taken with several other languages; in French, the sound "Atchoum!" is used; in Finnish "Atsiuh!"; in Swedish "Atjo"; in German "Hatschie!"; in Polish, "Apsik!"; in Turkish, "Hapşu!"; in Italian, "Etciù!"; in Spanish "Achú!"; in Portuguese, "Atchim!"; and in Japanese, "Hakushon!". In Cypriot Greek, the word is "Apshoo!", incidentally also the name of a village, which is the cause of much mirth locally. In Howards End, by E.M. Forster, a sneeze in polite society is "a-tissue" - a nice allusion to its respective remedy. Beliefs and Cultural AspectsIn the Hellenistic cultures of Classical Antiquity, sneezes were believed to be prophetic signs from the gods. In 410 BC, for instance, the Athenian general Xenophon gave a dramatic oration exhorting his fellow soldiers to follow him to liberty or to death against the Persians. He spoke for an hour motivating his army and assuring them of a safe return to Athens until a soldier underscored his conclusion with a sneeze. Thinking that this sneeze was a favorable sign from the gods, the soldiers bowed before Xenophon and followed his command. Another divine moment of sneezing for the Greeks occurs in the story of Odysseus. When Odysseus returns home disguised as a beggar and talks with his waiting wife Penelope, she says to Odysseus, not knowing to whom she speaks, that "[her husband] will return safely to challenge her suitors"". At that moment, their son sneezes loudly and Penelope laughs with joy, reassured that it is a sign from the gods.[citation needed] In Europe, principally around the early Middle Ages, it was believed that one's life was in fact tied to one's breath - a belief reflected in the word "expire" (originally meaning "to exhale") gaining the additional meaning of "to come to an end" or "to die". This connection, coupled with the significant amount of breath expelled from the body during a sneeze, had likely[citation needed] led people to believe that sneezing could easily be fatal. This theory, if proven conclusively, could in turn explain the reasoning behind the traditional "God bless you" response to a sneeze, the origins of which are currently unclear. In certain parts of Eastern Asia, particularly in Japanese culture, a sneeze without an obvious cause was generally perceived as a sign that someone was talking about the sneezer at that very moment. In China and Japan, for instance, there is a superstition that if you talk behind someone's back, the person in question will sneeze; as such, the sneezer can tell if something good is being said (one sneeze), something bad is being said (two sneezes in a row), or if this is a sign that they are about to catch a cold (multiple sneezes). In Indian culture, especially in northern parts of India, it has been a common superstition that a sneeze taking place before the start of any work was a sign of impending bad interruption. It was thus customary to pause in order to drink water or break any work rhythm before resuming the job at hand in order to prevent any misfortune from occurring. The practice among certain Islamic cultures, in turn, has largely been based on various Prophetic traditions and the teachings of Muhammed. An example of this is Al-Bukhaari's narrations from Abu Hurayrah that the Islamic prophet once said:
Traditional Responses to a SneezeIn English-speaking countries, a common response to a sneeze by those around it is "God bless you", or more commonly just "Bless you". The origins and purpose of this tradition are unknown, and several competing explanations have been proposed over time, with the majority focusing on the idea of preventing the soul from departing one's body, or as an effort to prevent possible death due to a lethal disease such as the plague of the fourteenth century. Today, it is said mostly in the spirit of good manners. In various other cultures, words referencing good health or a long life are used instead of "Bless you".
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