Lotus flower seeds University of Kent

**Warning, this post contains images which might cause feelings of intense disgust. All images were collected as part of the University of Kent's study into trypophobia**

Look at a bubble. Round, aerated, generally mysterious. But when do bubbles become nauseating?


From bubbles in a hot cup of coffee, to holes in a sponge or plaster, while the common appearance may seem innocuous it has been known to trigger intensely anxious responses. And that response has a name: Trypophobia.

What is Trypophobia and what causes it?

Trypophobia, characterised as the fear of holes, has also been linked to a more generalised aversion to circular shapes such as bubbles. But what makes bubbles so disgusting? The answer may be found lurking just under the skin.

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Boy's hand with smallpox scars University of Kent

Previous evidence suggested that the fear of bubbles stemmed from the clusters of round shapes found on poisonous animals, such as snakes and the blue-ringed octopus. But a new theory from psychologists at the University of Kent suggests our innate suspicion of rough circular shapes could, in fact, be linked to a history of human illness.


Foot with cluster marks University of Kent

Tom Kupfer, of the University's School of Psychology, noted that many infectious diseases result in clusters of round shapes on the skin: smallpox, measles, rubella, typhus, scarlet fever etc. Similarly, many ectoparasites, like scabies, ticks and botfly also lead to clusters of round shapes on the skin. In other words, if your skin starts popping, it's probably a bad sign.

Drilled holes in a wall University of Kent

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Kupfer recruited 300 trypophobia sufferers from various support groups, as well as 300 university students with no known history of the condition. Both groups were given 16 cluster images of real objects related to a diseased part of the body. Eight pictures were focused on images of illness - including but not limited to such nauseating sights as a cluster of ticks and a circular-shaped rash in the centre of someone's chest. The other eight images were unrelated to illness or disease, such as drilled holes in a brick wall, or lotus flower seeds.


A cluster of ticks on a dog's ear University of Kent

Both groups found the disease-related images to be unpleasant, whereas only the trypophobia sufferers found the non-disease related images to be extremely unpleasant. These findings suggest that individuals with trypophobia have heightened responses to bubble aversion, even in images with no underlying scenes of illness. But unlike most phobias, trypophobia results in intense feelings of disgust more often than fear.

Drilled holes in a tree University of Kent

Kupfer and his team then asked trial participants with trypophobia to describe their feelings when looking at cluster images. Analysis of these responses revealed that the majority of individuals with trypophobia experienced disgust or disgust-related feelings like nausea or the urge to vomit, even towards the disease-irrelevant cluster images like a sponge or bubbles. Only a small proportion described feeling fear or fear-related feelings.

Man's chest with a rash University of Kent

In addition to disgust, trypophobic individuals frequently reported feelings like skin itching, skin crawling or even the sensation of 'bugs infesting the skin'. This skin response suggests that people with trypophobia may perceive cluster stimuli as if they are cues to ectoparasites, even leading some to feel as if they are infested.


Waterbug with eggs on back University of Kent

Kupfer states that, "these findings support the proposal that individuals with trypophobia primarily perceive cluster stimuli as cues to ectoparasites and skin-transmitted pathogens".

Scrolling through the images, it's easy to see why these bubbles created such strong responses. If you've actually managed to pay attention to my words instead of the bulbous ticks and scars before you, congratulations. You can go throw up now.