Since the advent of the internet, people have been able to discuss their symptoms with others globally. Sometimes people with very unusual symptoms discover others with similar experiences, which they are then able to discuss without fear of ridicule.
Discussion forums and support groups are formed and eventually a new medical condition may be recognised. A case in point is "visual snow", which individuals experience as bright dots persistently floating like snow across their vision. Another is trypophobia.
Trypophobia - a "fear of holes" - is a condition which triggers individuals to suffer an emotional reaction when viewing seemingly innocuous images of clusters of objects, usually holes. The condition was first described on the internet in 2005 though it is not yet a recognised medical diagnosis.
The images responsible for the emotion include natural objects such as honeycomb or the lotus seed head, and man-made objects such as aerated chocolate or stacked industrial pipes viewed end-on. Despite their seemingly innocuous nature, images such as these (ideal for sharing on the internet) can induce a variety of symptoms including cognitive changes that reflect anxiety, bodily symptoms that are skin-related (such as itchiness and goose-bumps), and physiological changes (such as nausea, a racing heart, or trouble catching breath).