Obsessive-compulsive-like reasoning makes an unlikely catastrophe more credible

► Earlier studies have found that OCD-like perseveration induces uncertainty about memory and perception. ► OCD-like reasoning has perseverative features as well. ► When used by healthy participants, OCD-like step-by-step reasoning from a neutral situation to a catastrophic outcome enhances the credibility of negative, improbable outcomes that are feared by OCD patients. ► The perseverative reasoning style of OCD patients may be involved in the maintenance of their fears.