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Updated: Nov 5, 2025

Human Fear Conditioning Conducted in Full Immersion 3-Dimensional Virtual Reality
Published on: August 9, 2010
Priming with skin-problems increases fear of clusters.
Risako Shirai1,2, Hirokazu Ogawa3
1Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo, 169-8555, Japan. RisakoShirai@gmail.com.
The involuntary protection against dermatosis (IPAD) hypothesis suggests trypophobia stems from skin disease aversion. This study found that priming with skin problem words increased discomfort from trypophobic images, supporting the IPAD hypothesis.
Area of Science:
- Psychology
- Visual Perception
Background:
- Trypophobia is a discomfort triggered by clustered patterns.
- The involuntary protection against dermatosis (IPAD) hypothesis links trypophobia to an aversion to skin diseases.
Purpose of the Study:
- To empirically investigate the IPAD hypothesis by testing if activating skin disease concepts influences trypophobia.
- To examine the effect of priming with skin-related words on the evaluation of trypophobic images.
Main Methods:
- Participants completed a lexical decision task with skin-problem, negative, or neutral words.
- Following priming, participants rated the discomfort of trypophobic, negative, and neutral images.
- Experiment 2 attempted to replicate findings and test COVID-19 related priming.
Main Results:
- Exposure to skin-problem words significantly increased the perceived discomfort of trypophobic images.
- Priming with skin-related words did not affect the discomfort ratings of negative images.
- Experiment 2 failed to replicate the priming effect with skin-related or COVID-19 related words.
Conclusions:
- Findings from Experiment 1 provide initial empirical support for the IPAD hypothesis, suggesting a link between skin disease aversion and trypophobia.
- The lack of replication in Experiment 2 highlights the need for further research into the causal relationship between skin diseases and trypophobia.
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