Obsessional disorders: Obsessive-Compulsive Disorder OCD, Body Dysmorphic Disorder BDD and Health Anxiety are categorised as Anxiety Disorders, however, the CBT treatment differs substantially with that of other Anxiety Disorders.
The main reason is because the obsessional mind tends to rely on rational thinking to justify its obsessions, which in turn create compulsions. A person with obsessional tendencies often over-thinks experiences and internal processes, leading to compulsions which then reinforce the obsession and so forth. Once trapped in a thinking loop, one tries to get out of it by creating another thinking loop which leads to another thinking loop and so on. Specialised CBT treatment for obsessional tendencies seeks a clear understanding of the obsessional thinking process, learning how to get out of these thinking loops.