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Photic Sneeze – Bill Watson Essay, Research Paper

Robert M. Cavin3/27/99BIOL 221Photic Sneeze Bill Watson is a 36-year-old man, who worries about walking outside after a movie ends. This is his first date with this woman and he does not want to scare her off with odd behavior. He knows that people who do not suffer from the same condition do not understand. His hope is that maybe she also has this problem. However, he knows that there is little chance of this because he has never met anyone else who suffers from his problem. So he prepares for the embarrassment that follows his fit of sneezing caused by walking from the dark theater to the bright parking lot. Millions of people around the world suffer from photic sneezing. Although the condition is not uncommon, most people have never heard of it. The effects of photic sneezing can have a much greater impact than just embarrassing the sufferer, the most obvious being the effect on pilots and drivers. The danger of crashing aircraft or causing traffic accidents due to uncontrollable photic sneezing is the basis for debate on grounding pilots and suspending driver’s licenses. Studies conducted at universities and medical centers around the world have revealed no conclusive evidence on the exact physiological cause of photic sneezing. The studies have however found evidence of inheritance and gender preference. While many theories have arisen from these studies, the two most widely held are, squinting of the eyes cause lacrimal sacs to secrete tears into the nasal cavity, and the association of the optic nerve fibers and trigeminal nerve nucleus in the midbrain. The study conducted at the School of Optometry, University of Alabama at Birmingham, finds that females represent sixty-seven percent of photic sneezers. Ninety-four percent of those are Caucasian. The study also states that there is no correlation found between the presence of photic sneezing and the presence of a deviated septum and a non-significant association was found with tobacco use. The results of this study show that photic sneezing is more likely acquired than inherited. (Journal of American Optometry 1995 Jun; 66,6). N. Deshmukh conducted a study of photic sneezing and says “About twenty percent of people sneeze because of reflex action when exposed to sudden, bright light.” (The Guthrie Journal, 64(3):104-105) He also states that the study shows a strong autosomal dominant inheritance. This study shows no predominance in either sex, but did agree with earlier studies in that the problem most often occurred in Caucasians. However, there is a slight occurrence in Afro-Americans as well as Orientals. These studies show the importance of a controlled study being conducted. The results of these and many other published studies show that there is no one answer as to who will have the problem of photic sneezing. It may be inherent or acquired, it may be more prevalent in women than men, it may be totally random in who it selects. More controlled studies must be conducted to give people a firm answer. There are also many debates on the physiological cause of photic sneezing in these studies. One theory as to the physiological cause of photic sneezing according to the study conducted by R. A. Breitenbach is “The partial squinting of the eyes resulting from the bright light causes squeezing of the lacrimal sac which results in tears running down the nasolacrimal duct into the nasal cavity, causing stimulation of the nasal cavity and a sneeze.” (Military Medicine, 158). The subjects in these studies stated that they have no sensation of fluid running in their nose or sinuses prior to the sneezes. This is not consistent with the theory that enough fluid is in the nasal cavity to cause a sneeze. People suffering from a minor cold or sinusitis would be constantly sneezing if this were the case. An additional flaw in this theory is that the photic sneezes still occurred even when the person does not squint. Most of the studies on photic sneezing also state the sufferers sneeze between three to five times during an episode. If the sneezing is caused by a small amount of fluid running down the nasal cavity why would several more sneezes be necessary. This theory holds little credible evidence as a cause for photic sneezing. The following theory dealing with a neurological effect makes a much better argument. The second theory of R. A. Breitenbach is more credible in that he states “The mechanism of the bright light sneeze reflex seems to be an association of optic nerve fibers and trigeminal nerve nucleus in the mid-brain. The trigeminal nerve’s second division supplies sensory fibers to the nasal mucosa. It is postulated that nerve impulses travelling up the optic nerve will cause a sympathetic discharge down the trigeminal nerve fibers. (Military Medicine, 158). This theory caries more weight because it does not depend on the person squinting and not noticing fluid running in their nose to explain the sneezing. Sufferers describe the sensation as a sudden uncontrollable urge to sneeze and, nothing more. This study also states that many of the subjects can prevent photic sneezing by wearing sunglasses. Sunglasses prevent the sudden stimulation of the optic nerve preventing the sympathetic discharge down the trigeminal nerve fibers. Although there is no conclusive data on this phenomenon, Breitenbach’s neurological theory on photic sneezing makes the most sense physiologically. Approximately one fifth of the world population suffers from photic sneezing. However, people who do not suffer from the condition have normally never heard of photic sneezing. This is do to the fact that it is not as serious as many other conditions that plague humanity. A fact made evident by the small number of studies conducted on the subject. The studies currently available have explored the link to inheritance and gender preference. These studies also state theories on the cause of photic sneezing. Two of these theories are the lacrimal sacs secreting tears into the nasal cavity, and the association of the optic nerve fibers and the trigeminal nerve nucleus in the mid-brain. While Bill Watson merely worries about the embarrassment caused by the sneezing episodes, the consequences for pilots and drivers are much more serious. The studies conducted with them in mind have found that wearing sunglasses can prevent photic sneezing. The lack of conclusive data on the cause and the treatment leave it up to the sufferer to decide how much of a problem it presents to them. Most sufferers of photic sneezing accept it as a part of their life that they must live with. If it presents no great problem or threat as in the case of pilots or drivers, they just do not give it much thought. There are many occurrences in people’s lives that fall in to this category of unexplained annoyances. Until someone places enough importance on them to find the cause and cure they will remain just that, unexplained annoyances.

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Semes LP, Amos JF, Waterbor JW. “The Photic Sneeze Response: Descriptive Report of a Clinic Population.” Journal of American Optometry Association June 1995, 66(6): p372-377 [On-line], Available http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?db=m_dDeshmukh, N. “Sneezing response to bright light. Is it a cause of accidents?” The Guthrie Journal, 1995, 64(3): 104-105 [On-line], Available http://www.cathouse.org/medical/photic_sneeze.html Breitenbach, R.A, “The Photic Sneeze Reflex as a Risk Factor to Combat Pilots.” Military Medicine, 158, December 1993: 806-809 [On-line], Available http://www.cathouse.org/medical/photic_sneeze.html


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