Chapter 5.3 - Obsessive–Compulsive Disorder

Abstract

Obsessions include socially unacceptable thoughts or impulses, chronic doubting, fears of contamination, preoccupations with symmetry… Compulsions include excessive hand washing, placing objects symmetrically, repeatedly checking… The nature of the obsessions and compulsions varies greatly between patients with obsessive–compulsive disorder (OCD). The intrusive thoughts in OCD are perceived as the product of one’s own mind and are different from thought insertions in schizophrenia (SZ). The lifetime prevalence of OCD is more than twice of that in. Vulnerability to OCD is inherited but in many OCD patients a positive family history is absent. The neuropsychological profile of OCD reveals local deficits in inhibiting and planning motor and cognitive actions. In contrast to Attention Deficit Hyperactivity Disorder (ADHD) and SZ, OCD patients consistently show hyperactivation of the medial prefrontal cortex including the anterior cingulate area. The error-related negativity and conflict-related N2 ERP waves generated in the anterior cingulum are elevated in OCD and appear to be correlates of the feeling that things are “not just right.” The serotonergic system modulates OCD symptoms with SSRI producing clinical benefit. The other effective treatment is the Exposure and Response Prevention method of Cognitive Behavior Therapy. In 10–30% of cases severe OCD is resistant to conventional treatments so that psychosurgery and deep brain stimulation remain as the only options. Until recently reports on successful neurofeedback treatment in OCD were rare but individually tailored protocols could be beneficial. Inhibition of the presupplementary motor area by TMS or tDCS might be a promising protocol.