Emotion and internal experience in Obsessive Compulsive Disorder: Reviewing the role of alexithymia, anxiety sensitivity and distress tolerance

•Comprehensive review of understanding, sensitivity to and tolerance of emotion in OCD•Evidence that all three relate to OCD symptoms, but limited studies in patient groups•No evidence of specificity for OCD over other anxiety disorders•Lack of clarity around construct definition and subtypes of OCD clouds findings

Increasing attention has focused on the role of emotion and internal experience in Obsessive Compulsive Disorder (OCD). This review examines three key constructs that capture different aspects of understanding, appraisal and tolerance of internal states in OCD — alexithymia, anxiety sensitivity (AS) and distress tolerance (DT). The review examines the evidence for the role each of these constructs plays in OCD and considers whether conclusions can be drawn about the implications for our understanding and treatment of OCD. There is evidence that all three are elevated in clinical cases compared to controls, but there is no evidence that any of the three shows specificity for OCD over other anxiety disorders. However, the review has highlighted significant methodological heterogeneity and consequent variation in findings that currently limits broader conclusions from being drawn. There is an indication that this is a valuable area to explore and future studies should focus on deriving greater conceptual clarity around these constructs, independently replicating findings, and establishing a common methodology to enhance the comparability of studies. Studies exploring the ways in which internal experience, cognitions and symptoms may relate to one another would be of significant value in developing models that then lead to improved treatment approaches.