Existential obsessions-persistent, intrusive doubts about unanswerable questions such as the nature of reality, identity, free will, and death-are an understudied and underrecognized presentation of obsessive-compulsive disorder (OCD). Although these symptoms align with core OCD features, their abstract and philosophical content distinguishes them from more commonly studied presentations. This article provides a conceptualization of existential obsessions, outlining their phenomenology, cognitive-behavioral underpinnings, and implications for assessment and treatment. We identify four primary content domains, namely, metaphysical, thanatological, ontological, and deterministic obsessions, and draw on established OCD models to explain their development and maintenance. Sociocultural and developmental influences are also highlighted. We then outline treatment recommendations based on the conceptual model and present a research agenda to address gaps in the literature, including the need for targeted assessment tools, empirical tests of proposed mechanisms, and treatment trials. Just as other manifestations of OCD have gained clarity through empirical study, existential obsessions merit scientific attention to enhance recognition and improve outcomes.
Keywords: acceptance-based approaches; cognitive-behavioral therapy; existential obsessions; exposure therapy (with response prevention); obsessive–compulsive disorder; philosophical obsessions; worry.
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