One-session treatment for trypophobia: a controlled multiple baseline trial.

Trypophobia, an aversion to clustered patterns such as lotus seed pods or honeycombs, has been increasingly recognised as a condition associated with both fear and disgust. Despite its prevalence and significant functional impairment, few studies have examined effective treatments. The current study developed and evaluated a novel One-Session Treatment (OST) for trypophobia designed to target both emotional components. Traditional OST, an intensive cognitive-behavioural therapy combining psychoeducation, cognitive challenges, modelling, and exposure, was augmented with counterconditioning (pairing an aversive stimuli with pleasant experiences) and revaluation techniques to modify negative valence. Using a multiple-baseline single-case controlled design, participants were randomly assigned to a 1-, 2-, or 3-week baseline conditions before receiving the intervention. Trypophobic symptoms, diagnostic status, and performance on a behavioural approach task were assessed pre-treatment, post-treatment, and at 1-month follow-up. Symptoms remained stable during the baseline period but showed significant reductions following treatment, with gains maintained at 1-month follow-up. Both fear and disgust towards trypophobic stimuli decreased, and participants demonstrated increased approach behaviour. These findings support the preliminary effectiveness of an intensive, augmented OST in addressing both affective dimensions of trypophobia and highlight the possibility that targeting disgust-based avoidance processes may be beneficial for improving outcomes.