Photic Sneeze Reflex

Sometimes referred to using the backronym Autosomal Dominant Compelling Helio-Ophthalmic Outburst Syndrome (ACHOO Syndrome), and colloquially known as "sun sneezing". A condition of uncontrollable sneezing in response to numerous stimuli, such as looking at bright lights, affects 18–35% of the population. Its exact mechanism of action is not well understood.



Hinode Observes 2011 Annular Solar Eclipse by NASA Goddard Photo and Video, on Flickr