That Can Make you Sneeze?


My one friend from home always used to tell me that when he would walk into bright sunlight, he would sneeze.  My first reaction, "yeah, okay bud".  A few weeks later he came up to me and insisted that the sun making you sneeze was a legitimate phenomena, as it turns out, I (begrudgingly) had to admit that he was right.

For some people, this sight is enough to elicit a sneeze reaction.

As it turns out, there is a condition called Photic Sneeze Reflex that is responsible for this behavior.  According to an article from The Scientific American, this condition has been investigated since the ancient philosophers, being mentioned in a text by Aristotle, as well as investigated by Francis Bacon and others. 


Today, with our modern physiological understanding of humans, scientists has thus far been able to conclude that this reaction is the resultof crossed wires in the brain.  While the mechanism behind this hypothesis is not certain, there are theories.  The most prominent theory of the mechanism behind this reaction involves the Optic Nerve and the Trigeminal Nerve. 


The Trigeminal nerve is responsible for motor control and facial sensations, when the nose is tickled, it is sensed by the Trigeminal Nerve, which sends a signal to the brain that triggers a sneezing reaction.  The Optical Nerve, is the nerve respoinsible for dealing with the eyes.  When the Optical Nerve senses an intense amount of bright sunlight, it send s a signal to the brain to constrict the pupils.  Neurologists believe that these wires get crossed and as the Optical Nerve send the message to the brain to constrict the pupils, it also triggers the Trigeminal Nerve which causes a sneeze reaction. 



The Trigeminal and the Optic Nerves


Approximately 10-35% of the population are categorized as "photic sneezers".  A rather large portion of the population for such a unwellknown disorder.  As this disorder is not known to cause much distress or life interference, very little research has been done on it.  But, some scientists believe that more research on this genetic anomaly may provide some insight into Epilepsy caused by intense photic sensations (strobe lights, flashing lights, etc.).


In my opinion, this reflex is an actual genetic anomaly and not just a natural relfex that ha sbeen pathologized (turned into a disorder). I believe that this reflex is nothing more than a slight nuisance, but it's potential connection to Epilepsy may be worth looking into.  I don't believe that any research should be done on how to "cure" the Photic Sneeze Reflex should be done, but I do think that it would be worthwhile to the scientific community to look into the genetic mechinism behind it to see if there is any potential connection to epilepsy, a potentially life threatening disorder.


What do you think?

Does Photic Sneeze Reflex really exist or is it just a normal reaction that has been pathologized or an illusory correlation?

Should moer research be devoted to Photo Sneeze Reflex, or should our precious funding be spent somewhere else such as Cancer or Alzheimer's research?



I definitely do believe that photic sneeze reflexes exist. Like your friend I always sneeze every time I look at the sun. It is interesting because whenever I tweeze my eyebrows I also sneeze. I would not consider this a disease and I agree with you that it has been pathologized and turned into a disorder. It would be very interesting for more research to be done and for actual experiments to take place but I do believe there are other subjects that are more important to focus on at the time.

This blog is interesting to me because I always sneeze when I look near the sun. When I was a kid I used to tell people I was "allergic to the sun." That was obviously an incorrect statement, but people did agree with me that the sun made them sneeze. I looked at the Wikipedia page for photic sneezing and learned some facts about it that I didn't know. The amount of people that have the condition surprised me. Wikipedia had slightly different numbers than you. They claim that 18-35% of people have the photic sneeze reflex. Another thing that the Wikipedia page pointed out that I never thought of was the risks of photic sneezing. Risks include disease transmission, effects on vehicle operation, and problems with medical procedures. I never thought of sneezing at the sun to be a risk. I also thought about something that could be possible. I have the photic sneeze reflex and I have blue eyes. I wonder if people with blue eyes are more likely to sneeze from the sun that people with other colored eyes. It's definitely a hypothesis that could be tested.

After reading your blog, I do believe that it is possible that Photic Sneeze Reflex exists. I do also believe that we should focus more on Cancer and Alzheimer's than this possible sneeze reflex. This is for obvious reasons like Cancer and Alzheimer's need to find cures so more people can live happy, healthy lives and the Photic Sneeze Reflex is extremely minor compared to them. However, the world is full of scientists that invent and discover new things everyday and there are plenty out there that would research this topic. 10 - 35% of the population is a good amount of the population. If this Photic Sneeze Reflex does exist I do not think I suffer from it. I have heard before that if you want/have to sneeze to look at the sun, however it never worked for me. I guess my Trigeminal and Optic nerves never get crossed!

I don't know what it is, but I'm glad somebody looked this up. Whatever it may be, whenever i stare directly at the sun I sneeze. I'm not to sure about the whole Photic Sneeze Reflex, but there seems to be some evidence proving it. I wouldn't say that I have it, but the fact that I sneeze due to light sensitivity is skeptical.

Leave a comment

Subscribe to receive notifications of follow up comments via email.
We are processing your request. If you don't see any confirmation within 30 seconds, please reload your page.

Search This Blog

Full Text  Tag

Recent Entries

Everyone has heard of them as being the best car out there, mainly cause of gas prices. Hybrids are sweeping…
People everywhere are breaking up, just in time for the holidays. And the more couples I see parting ways, the…
Pregnancy Tests
While browsing Andrew's blog and looking to see all of the posts that I missed (I'm pretty sure I haven't…

Old Contributions