Christopher DiMattina¹ (), R. Nathan Pipitone, Martin R. Renteria, Kriston J. Ryan; ¹Florida Gulf Coast University

Trypophobia is the discomfort felt by some individuals when viewing images containing clusters of bumps or holes. Several evolutionary hypotheses have been proposed to explain this phenomenon, with more current literature supporting the notion that visual discomfort functions as part of the behavioral immune system, helping organisms avoid skin disease and/or ectoparasites. Although both skin disease imagery and trypophobic imagery are visual textures, to date there has been no direct comparison of the visual discomfort elicited by these textures in the larger context of the discomfort elicited by a wider variety of natural textures. In this study, we measured participants level of trypophobia using the Trypophobia Questionnaire (TQ) and recorded the visual comfort ratings elicited by a large set of natural texture images from the Brodatz database, trypophobic textures, and skin disease textures. Results showed that while all observers find skin diseases uncomfortable to view, only those scoring high on the TQ rated trypophobic imagery equally uncomfortable. We further observe that the high-TQ participants rated skin disease images as being significantly more uncomfortable than low-TQ participants. Comparing the ratings for high-TQ and low-TQ participants to the standard textures, we find remarkably consistent rank-order preferences, with the most unpleasant textures (as rated by both groups) exhibiting qualitative similarities to trypophobic imagery. However, we find that low-level image statistics which have been previously shown to affect visual comfort are poor predictors of the visual comfort elicited by natural textures, and greatly under-predict the visual discomfort elicited by trypophobic or disease imagery. Our results suggest that a full understanding of the visual comfort elicited by natural textures, including those arising from skin disease, will ultimately depend upon a better understanding of the perception of surface and material properties, and how these percepts of surface and material properties evoke appropriate behavioral responses like disgust.