Ramesh Perera-Delcourt, Robert A. Nash, Susan J. Thorpe

Background: Recent work on cognitive-behavioural models of obsessive-compulsive disorder has focused on the roles played by various aspects of self-perception. In particular, moral self-ambivalence has been found to be associated with obsessive-compulsive phenomena. Aims: In this study we used an experimental task to investigate whether artificially priming moral self-ambivalence would increase participants' deliberation on ethical problems, an index that might be analogous to obsessive-compulsive behaviour. Method: Non-clinical participants completed two online tasks designed to prime either moral self-ambivalence, general uncertainty, or neither. All participants then completed a task requiring them to consider solutions to moral dilemmas. We recorded the time participants took to respond to the dilemmas and the length of their responses; we then combined these variables to create a measure of deliberation. Results: Priming moral self-ambivalence led to increases in deliberation, but this was only significant among those participants who scored highly on a baseline measure of moral self-ambivalence. Priming general uncertainty had no significant effect upon deliberation. Conclusions: The results suggest that moral self-ambivalence may play a role in the maintenance of obsessive-compulsive behaviour. We propose that individuals who are morally self-ambivalent might respond to situations in which this ambivalence is made salient by exhibiting behaviour with obsessive-compulsive characteristics. These findings have implications for the incorporation of ideas about self-concept into theories of obsessive-compulsive disorder.