Obsessive‐compulsive disorder: Etiology, neuropathology, and cognitive dysfunction

Abstract

Background This review provides an overview of obsessive‐compulsive disorder (OCD) symptoms, including the four partially distinct subtypes of the disorder, current diagnostic criteria, and common comorbidities. Critically, it focuses on the etiology of OCD, including its underlying neuropathology, and examines cognitive dysfunction in OCD. Methods This review study was conducted by library method. Results We show how dysfunction in cortico‐striato‐thalamo‐cortical (CSTC) circuits may underpin symptoms; and shed light on the putative neurochemistry within these loops such as the role of serotonin, dopamine, and glutamate systems. We also show how OCD is characterized by cognitive dysfunction including problems in cognitive flexibility, visuospatial memory, response inhibition, and goal‐directed behavior, linked to aberrant activity within CSTC circuits. Conclusions In brief, research questions we shed light on include (1) what are the symptoms in OCD; (2) what is the etiology of the disorder and do existing models explain OCD; and (3) what are key cognitive deficits in OCD and do these improve with treatment?

The Efficacy of Transcranial Magnetic Stimulation in the Treatment of Obsessive-Compulsive Disorder: An Umbrella Review of Meta-Analyses

“…28 All the studies conducted before and after the FDA approval of TMS for OCD treatment have focused on the abnormal function of the cortico-striato-thalamo-cortical (CSTC) circuitry, which plays a crucial role in the mechanisms of OCD. 6,7 Similar abnormal neural oscillations have also been observed in other brain areas associated with neuropsychiatric conditions. 29,30 In OCD, an imbalance between the direct and indirect pathways of the CSTC circuitry contributes to the generation and perpetuation of obsessions and compulsions, which are the key symptoms of OCD.…”

“…Results showed that at 1-month follow-up, 45.2% of the patients in the active treatment group responded, compared to 17.8% in the sham treatment group 28 . All the studies conducted before and after the FDA approval of TMS for OCD treatment have focused on the abnormal function of the cortico-striato-thalamo-cortical (CSTC) circuitry, which plays a crucial role in the mechanisms of OCD 6 , 7 . Similar abnormal neural oscillations have also been observed in other brain areas associated with neuropsychiatric conditions 29 , 30 .…”

“…1 Neuroimaging studies consistently indicate the involvement of the cortico-striato-thalamocortical (CSTC) circuitry in patients with OCD. [5][6][7] Various neuromodulation techniques, ranging from invasive techniques like deep brain stimulation to convulsive techniques like electroconvulsive therapy, have been used in the management of OCD. 8 Studies report that among patients with OCD, all the neuromodulation techniques are used as an add-on treatment to ongoing pharmacological treatment.…”

Link Between Obsessive-Compulsive Disorder and ApoE Gene Polymorphisms

“…The problems in visual memory and visuospatial ability have been shown in studies on motor slowing. 24 , 25 Jalal et al (2010) 26 compared OCD symptomatology with non-verbal memory and organizational strategies, and observed that the group with symmetry/ordering and checking obsessions were following a significantly and progressively worsening disease course. In this study, it has been agreed that the disruption between checking obsessions and non-verbal memory is related to anxiety rather than symmetry obsession.…”

Microbial Reprogramming in Obsessive–Compulsive Disorders: A Review of Gut–Brain Communication and Emerging Evidence

“…Indeed, although OCD is now recognized as an independent disorder category, it often occurs with other disorders such as autism, attention deficit hyperactivity disorder (ADHD), depression, general anxiety disorder, eating disorder, hoarding disorder, Tourette syndrome, panic disorder, or schizophrenia [5]. This category includes other disorders such as hoarding disorder, hair-pulling disorder, and skin-picking disorder [6].…”