Psychiatry Research EG

Obsessive–compulsive disorder (OCD) is characterized by the presence of either obsessions or compulsions that cause significant distress in afflicted individuals. OCD is a relatively frequent psychiatric disorder with the 12-month prevalence in adults ranging from 0.6 to 1.0%, according to the Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV), and an estimated lifetime of 1.6%. Estimates of prevalence vary slightly across countries depending on different research methodologies [1]. Neurological soft signs (NSSs) are minor neurological abnormalities that are thought to be secondary to a neurodevelopmental abnormality; they cannot be localized by brain screening tests. These signs may reflect brain dysfunctions in psychiatric disorders. NSSs can be generally grouped as sensory integration, motor coordination, sequencing of complex motor acts, and others [2]. Although contradictory results have been reported by studies evaluating NSSs in OCD patients, graphesthesia disorder, among the sensory integration subgroup of NSSs, is consistently found to be more common in OCD patients in studies comparing NSS subscale scores separately. In the literature, we can find only one study that compares OCD and schizophrenia patients in terms of NSSs, which is the study by Tumkaya and colleagues. In their study, schizophrenia patients performed worse than OCD patients in all NSS subgroups except sensory integration [2]. In the context of OCD, deficits in nonverbal memory and certain executive functions such as set shifting abilityresponse inhibition, and decision making have been widely reported [3]. Two studies have demonstrated the presence of such deficits in remitted patients [4]. There have been two studies in this regard that revealed deficits in planning and in response inhibition and set shifting [5] in relatives of index probands. However, these studies choose more than one type of unaffected first-degree relatives, and samples combining more than one generation of relatives may be biased due to the differing neurodevelopmental stages of participants.