Obsessive-compulsive disorder (OCD) is a common psychiatric condition classically characterized by obsessions (recurrent, intrusive and unwanted thoughts) and compulsions (excessive, repetitive and ritualistic behaviors or mental acts). OCD is heterogeneous in its clinical presentation and not all patients respond to first-line treatments. Several neurocircuit models of OCD have been proposed with the aim of providing a better understanding of the neural and cognitive mechanisms involved in the disorder. These models use advances in neuroscience and findings from neuropsychological and neuroimaging studies to suggest links between clinical profiles that reflect the symptoms and experiences of patients and dysfunctions in specific neurocircuits. Several models propose that treatments for OCD could be improved if directed to specific neurocircuit dysfunctions, thereby restoring efficient neurocognitive function and ameliorating the symptomatology of each associated clinical profile. Yet, there are several important limitations to neurocircuit models of OCD. The purpose of the current review is to highlight some of these limitations, including issues related to the complexity of brain and cognitive function, the clinical presentation and course of OCD, etiological factors, and treatment methods proposed by the models. We also provide suggestions for future research to advance neurocircuit models of OCD and facilitate translation to clinical application.

The World Health Organization (WHO) is currently revisiting the ICD. In the 10th version of the ICD, approved in 1990, hypochondriacal symptoms are described in the context of both the primary condition hypochondriacal disorder and as secondary symptoms within a range of other mental disorders. Expansion of the research base since 1990 makes a critical evaluation and revision of both the definition and classification of hypochondriacal disorder timely. This article addresses the considerations reviewed by members of the WHO ICD-11 Working Group on the Classification of Obsessive-Compulsive and Related Disorders in their proposal for the description and classification of hypochondriasis. The proposed revision emphasizes the phenomenological overlap with both anxiety disorders (e.g., fear, hypervigilance to bodily symptoms, and avoidance) and obsessive-compulsive and related disorders (e.g., preoccupation and repetitive behaviors) and the distinction from the somatoform disorders (presence of somatic symptom is not a critical characteristic). This revision aims to improve clinical utility by enabling better recognition and treatment of patients with hypochondriasis within the broad range of global health care settings.