The aime of this study was to investigate a transdiagnostic model for explaining comorbidity between anxiety and depression based on the overcontrolling, sensivity to reward and sensivity to threat.The participants were 586 students of Islamic Azad University Tabriz Branch, University of Tabriz and Azarbaijan Shahid Madani University in Iran. Data were collected by Depression Anxiety Stress Scale (DASS-21), Acceptance and Action Questionnaire (AAQ-II), behavioural inhibtion/Behavioural activation scale (BAS/BIS), Intolerance of Uncertainty Scale (IUS), Ambivalence over Emotional Expression Questionnaire (AEQ) and Frost Multidimensional Perfectionism Scale (FMPS). Sensitivity to reward with overcontrolling mediation affects anxiety and depression with standard coefficients of -0.29 and -0.36. Also, sensitivity to threat with standardized coefficients of 0.31 and 0.39, respectively, have a significant effect on anxiety and depression by the mediation of overcontrolling. Our findings proposes a suitable framework for explaining comorbidity between depression and anxiety. Low sensitivity to reward and high sensitivity to threat by the mediation role of overcontrolling could predict comorbidity between anxiety and depression. These findings can be useful in understanding the etiology of comorbid emotional disorders, and developing efficacious therapeutic interventions and prevention of comorbid emotional disorders.
