The behavioral inhibition system (BIS) mediates major aspects of the relationship between disgust and OCD symptomology

• Influence of a behavioral inhibition system (BIS) and disgust on OCD was examined.
• Disgust was exclusively related to washing and ordering symptoms.
• BIS was exclusively related to symptoms of hoarding.
• BIS mediated disgust effects on OCD symptoms of checking and obsessing.

Disgust is highly related to obsessive-compulsive disorder (OCD) symptoms, yet its contribution to specific OCD symptoms is still unclear. In the present study, we examined how disgust–OD relationship is influenced by the behavioral inhibition system (BIS), a personality variable that co-varies with disgust and OCD. A large heterogeneous sample (N=314), taken from the general population (using a convenience sampling method), completed a self-reported questionnaires of disgust (The Disgust Scale Revised), behavioral inhibition (The behavioral inhibition system questionnaire) and OCD symptoms (Obsessive-Compulsive Inventory-Revised). In addition, demographic factors, related to both disgust and OCD, were collected. The findings indicated that disgust and BIS were related to both shared and different elements of OCD. Disgust was exclusively related to symptoms of washing, while BIS was exclusively related to symptoms of hoarding. Both disgust and BIS influenced ordering. Furthermore, BIS mediated part of the relationship between disgust and OCD symptoms, namely, checking and obsessing, and to a lesser extent, neutralizing. We present a model, supported by a confirmatory factor and mediation analyses, suggesting that disgust and BIS are related to mostly different aspects of OCD: while disgust is related mainly to the contamination aspect of OCD, BIS is related to difficulties in behavior inhibition.