Fear of Holes May be an Evolutionary Survival Response: Strange Phobia Unraveled

When you think of phobias, your mind may first go to the most common ones: heights, spiders and snakes. Rarely do people consider the fear of holes. Yet there are those who suffer from trypophobia who can't stand the sight of soap bubbles or aerated chocolate. Now, scientists have discovered that trypophobia may be an evolutionary survival response.

For those who suffer from trypophobia, the sight of clusters of holes in various formations can cause intensely unpleasant reactions. They can result in panic attacks, hot sweats, an increased heart rate or even migraines. Yet this phobia may result from a very specific visual feature also found among poisonous animals.

In order to study trypophobia a bit more closely, researchers compared 76 images of trypophobic objects with 76 control images of holes not associated with trypophobia. They then standardized the various features of the images.

What did they find? It turns out that the tryopophobic objects had relatively high contrast energy at midrange spatial frequencies in comparison to the control images. In fact, they had the same visual structure as stripes, which also cause migraines for some people. In order to find out why this particular visual cue causes this type of reaction, though, the scientists investigated a bit further.

The next step was to examine an animal that one trypophobia sufferer had said caused an adverse reaction: the blue-ringed octopus. This creature is one of the most poisonous in the world. Intrigued by this fact, the researchers decided to examine other poisonous creatures. It turned out that creatures such as the deathstalker scorpion, king cobra snake and other poisonous snakes tended to have the same visual cues associated with trypophobia.

"We think that everyone has trypophobic tendencies even though they may not be aware of it," said Cole, one of the researchers, in a news release. "We found that people who don't have the phobia still rate trypophobic images as less comfortable to look at than other images. It backs up the theory that we are set up to be fearful of things which hurt us in our evolutionary past. We have an innate predisposition to be wary of things that can harm us."

The findings are published in the journal Psychological Science.