Objectives The aim of this study was to evaluate the structural relationships between behavioral brain systems, disgust sensitivity, and obsessive-compulsive disorder using structural equation modeling. It is assumed that the behavioral brain systems and disgust sensitivity in interaction with each other will lead to obsessive-compulsive disorder. Despite the prominence of this model, not enough research has been done to assess its experimental.
Methods In a descriptive-correlation study, a sample of 340 students from Tabriz University was selected using cluster sampling method. Participants responded to Inventory system activation / inhibition of behavior (Carver and White, 1994), The Disgust Sensitivity Scale, Obsessive Compulsive Inventory- Revised (OCI-R). Data were analyzed using Structural Equation Modeling (SEM).
Results The evaluation of hypothetical model with fit indexes demonstrated that the hypothetical model fits the measurement model (CFI=0.96, NFI=0.94, and RMSEA=0.076). BIS and BAS with standardized coefficients of 0.264 and -0.241, respectively, have a significant effect on obsessive-compulsive disorder by the mediation of disgust sensitivity at the P˂0.05 level.
Conclusion The result, supporting the theoretical model for obsessive-compulsive disorder, proposes a suitable framework for the etiology of the disorder. Accordingly, high sensitivity of BIS and low sensitivity of BAS by the mediation of disgust sensitivity due to an increase in the symptoms of OCD.