Quantification of glutathione and its associated spontaneous neuronal activity in major depressive disorder and obsessive-compulsive disorder.

BACKGROUND: Glutathione (GSH) is a crucial antioxidant in the human brain. Although proton magnetic resonance spectroscopy (MRS) using the MEscher-GArwood Point RESolved Spectroscopy (MEGA-PRESS) sequence is highly recommended, limited literature has measured cortical GSH using this method in major psychiatric disorders. METHODS: By combining MRS using the MEGA-PRESS and resting-state functional magnetic resonance imaging, we quantified brain GSH and glutamate in the medial prefrontal cortex (mPFC) and precuneus and explore relationships between the GSH levels and intrinsic neuronal activity as well as clinical symptoms among the three groups of healthy controls (HCs, N=30), major depressive disorder (MDD, N=28), and obsessive-compulsive disorder (OCD, N=28). RESULTS: GSH concentrations were lower in both the mPFC and precuneus in both the MDD and OCD groups compared to HCs. In HCs, positive correlations were noted between the GSH and glutamate levels, and between GSH and fractional amplitude of low-frequency fluctuations (fALFF) in both regions. However, while these correlations were absent in both patient groups, they showed a weak positive correlation between glutamate and fALFF values. Moreover, GSH levels negatively correlated with depressive and compulsive symptoms in MDD and OCD, respectively. CONCLUSIONS: These findings suggest that reduced GSH levels and an imbalance between GSH and glutamate could increase oxidative stress and alter neurotransmitter signaling, leading to disruptions in GSH-related neurochemical-neuronal coupling and psychopathologies across MDD and OCD. Understanding these mechanisms could provide valuable insights into the underlying processes of these disorders, potentially becoming a springboard for future directions and advancing our knowledge of their neurobiological foundations.

Hereditary Patterns and Genetic Associations in Obsessive-Compulsive Disorder (OCD): Neuropsychiatric Insights, Genetic Influences, and Treatment Perspectives.

Obsessive-Compulsive Disorder (OCD), a prevalent neuropsychiatric condition, affects approximately 2%-3% of the global population. This paper provides an extensive overview of OCD, detailing its clinical manifestations, neurobiological underpinnings, and therapeutic approaches. It examines OCD's classification shift in the DSM-5, the role of the cortico-striatothalamo- cortical pathway in its development, and the various factors contributing to its etiology, such as genes, environmental factors, and genetic predispositions. The challenges in diagnosing OCD and the effectiveness of both psychological and pharmacotherapeutic treatments are discussed. The paper also highlights the significant overlap between OCD and other mental health disorders, emphasizing its impact on global disability. Moreover, the role of genetic factors in OCD, including twin studies and gene association studies, is elaborated, underscoring the complex interplay of hereditary and environmental influences in its manifestation. The review further delves into the polygenic nature of OCD, illustrating how multiple genes contribute to its development, and explores the implications of genetic studies in understanding the disorder's complexity. Additionally, this research study delves into the concept of polygenic inheritance in complex diseases, highlighting the role of multiple genes in increasing OCD risk. A Genome-wide Association Study (GWAS) is employed to assess Single Nucleotide Polymorphisms (SNPs) to unearth genetic associations with OCD. This comprehensive analysis provides valuable insights into OCD's genetic landscape, paving the way for enhanced diagnostic approaches and treatment modalities.

Religious scrupulosity and early maladaptive schemas: a network analysis.

Scrupulosity is treated as a particular presentation of the symptomatology characteristic for obsessive-compulsive disorder (OCD). However, typical treatment of OCD (e.g. cognitive-behavioral therapy) is less effective in the case of religious scruples. Recently, schema therapy has appeared as an alternative effective treatment in obsessive-compulsive symptomatology. The present study investigated the associations between early maladaptive schemas (EMSs) and scrupulosity in a non-clinical sample of 376 poles. The participants assessed their EMSs with the Young Schema Questionnaire 3 - Short Form and their scrupulosity with the Pennsylvania Inventory of Scrupulosity. We used network analysis to control for the EMS interconnectivity. We showed that accounting for the interactions within the EMSs, three schemas, namely, Punitiveness, Subjugation, and Enmeshment/Undeveloped Self, were positively correlated with scrupulosity. Given the central position of the Negativity/Pessimism schema in the examined network, we suggested that activation of this schema could be indirectly correlated to scruples via an escalation of activation to the Punitiveness, Subjugation, and Enmeshment schemas. The findings suggest that dependency and fear of rejection problems (present in Subjugation and Enmeshment EMSs) and over-compensation by perfectionism (present in Punitiveness EMS) could be addressed in the treatment of scruples.

Obsessive-compulsive symptoms in dementia: Systematic review with meta-analysis.

Dementia is a highly prevalent syndrome with various causes, characterized by cognitive deficit in one or more domains, with important impairment of functioning, which frequently presents with neuropsychiatric symptoms that may include obsessive-compulsive symptoms. OBJECTIVES: The main goal of this meta-analysis was to describe and determine the prevalence of obsessive-compulsive symptoms in dementia. MATERIALS AND METHODS: To accomplish that, MEDLINE, CENTRAL and Psycnet databases were searched from inception to March 2023. The Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data was applied. The principal summary measures were the mean of prevalence of obsessive-compulsive symptoms in patients with dementia and the number of each type of obsession or compulsion. RESULTS: Of the 643 articles screened, 92 were accepted for full-text assessment. Of these, 30 with information on prevalence of obsessive-compulsive symptoms in dementia or any description of those were included, yielding a total of 37 cohorts (5 studies with two cohorts and 1 study with three cohorts). According to our results, obsessive-compulsive symptoms have considerable prevalence in dementia (35.3%, 23.1-47.6%), namely in frontotemporal dementia (48.4%, 29.8-67.0%); obsessive-compulsive symptoms were less frequent in other dementia diagnosis (17.6%, 9.1-26.2%). The more frequent obsessive contents are symmetry (28.6%) and somatic (20.0%); and the more frequent compulsions are checking (27.4%); hoarding is also a relevant symptom (27.8%). DISCUSSION: There was considerable heterogeneity in the prevalence of obsessive-compulsive symptoms in frontotemporal dementia, that is, in part related with diagnostic criteria for dementia, as well as obsessive-compulsive symptom assessment. A careful distinction between compulsions and compulsive-like symptoms is fundamental. Hypervigilance for somatic symptoms and concerns about disease and mortality, as well as deficits in cognitive domains like attention and memory may explain why somatic obsessions and checking compulsions are more prevalent. CONCLUSIONS: The present results indicate that obsessive-compulsive symptoms may be prevalent in the clinical course of many patients with dementia, especially frontotemporal dementia. Better instruments are needed to describe obsessive-compulsive phenomena in a reliable and comparable way, particularly in a population such as dementia patients, whose subjectivity is difficult to access.

The role of the district nurse providing care to service users with obsessive compulsive disorder.

Service users living with Obsessive compulsive disorder (OCD) often delay or avoid seeking diagnosis or treatment because of a fear of judgement or feelings of shame associated with their obsessions and compulsions. They may feel that their behaviour defies societal norms, which can lead to social isolation, and in turn, further contribute to health inequality. When such individuals present with physical illness and are seen by district nurses, it is imperative that behaviours are understood and approached appropriately. It is important to develop therapeutic relationships and consider their holistic wellbeing. Developing a close working relationship with the mental health team as a multidisciplinary team and using the team as a resource may contribute to the overall health outcome of service users with OCD.

Modeling the Determinants of Subjective Well-Being in Schizophrenia.

BACKGROUND: The ultimate goal of successful schizophrenia treatment is not just to alleviate psychotic symptoms, but also to reduce distress and achieve subjective well-being (SWB). We aimed to identify the determinants of SWB and their interrelationships in schizophrenia. METHODS: Data were obtained from 637 patients with schizophrenia enrolled in multicenter, open-label, non-comparative clinical trials. The SWB under the Neuroleptic Treatment Scale (SWN) was utilized; a cut-off score of 80 indicated a high level of SWB at baseline and 6 months. Various machine learning (ML) algorithms were employed to identify the determinants of SWB. Furthermore, network analysis and structural equation modeling (SEM) were conducted to explore detailed relationship patterns. RESULTS: The random forest (RF) model had the highest area under the curve (AUC) of 0.794 at baseline. Obsessive-compulsive symptoms (OCS) had the most significant impact on high levels of SWB, followed by somatization, cognitive deficits, and depression. The network analysis demonstrated robust connections among the SWB, OCS, and somatization. SEM analysis revealed that OCS exerted the strongest direct effect on SWB, and also an indirect effect via the mediation of depression. Furthermore, the contribution of OCS at baseline to SWB was maintained 6 months later. CONCLUSIONS: OCS, somatization, cognition, and depression, rather than psychotic symptoms, exerted significant impacts on SWB in schizophrenia. Notably, OCS exhibited the most significant contribution not only to the current state of well-being but also to follow-up SWB, implying that OCS was predictive of SWB. The findings demonstrated that OCS management is critical for the treatment of schizophrenia.

Cerebrospinal fluid characteristics of patients presenting for evaluation of pediatric acute-neuropsychiatric syndrome.

Objectives: This study characterizes cerebral spinal fluid (CSF) indices including total protein, the albumin quotient, IgG index and oligoclonal bands in patients followed at a single center for pediatric acute-neuropsychiatric syndrome (PANS) and other psychiatric/behavioral deteriorations. Methods: In a retrospective chart review of 471 consecutive subjects evaluated for PANS at a single center, navigational keyword search of the electronic medical record was used to identify patients who underwent lumbar puncture (LP) as part of the evaluation of a severe or atypical psychiatric deterioration. Psychiatric symptom data was ascertained from parent questionnaires and clinical psychiatric evaluations. Inclusion criteria required that subjects presented with psychiatric deterioration at the time of first clinical visit and had a lumbar puncture completed as part of their evaluation. Subjects were categorized into three subgroups based on diagnosis: PANS (acute-onset of severe obsessive compulsive disorder (OCD) and/or eating restriction plus two other neuropsychiatric symptoms), autoimmune encephalitis (AE), and "other neuropsychiatric deterioration" (subacute onset of severe OCD, eating restriction, behavioral regression, psychosis, etc; not meeting criteria for PANS or AE). Results: 71/471 (15.0 %) of patients underwent LP. At least one CSF abnormality was seen in 29% of patients with PANS, 45% of patients with "other neuropsychiatric deterioration", and 40% of patients who met criteria for autoimmune encephalitis. The most common findings included elevated CSF protein and/or albumin quotient. Elevated IgG index and IgG oligoclonal bands were rare in all three groups. Conclusion: Elevation of CSF protein and albumin quotient were found in pediatric patients undergoing LP for evaluation of severe psychiatric deteriorations (PANS, AE, and other neuropsychiatric deteriorations). Further studies are warranted to investigate blood brain barrier integrity at the onset of the neuropsychiatric deterioration and explore inflammatory mechanisms.

Repetitive transcranial magnetic stimulation for major depression and obsessive-compulsive disorders in Singapore.

Introduction: Repetitive transcranial magnetic stimulation (rTMS) is used for treatment-resistant major depressive disorder (MDD) and obsessive-compulsive disorder (OCD), but there are few studies on patient outcomes in Southeast Asia. In this study, we describe the clinical profile and outcome of patients with MDD and OCD treated with rTMS in Singapore. Method: A naturalistic retrospective study of 71 patients (inpatient and outpatient) who received rTMS treatment between June 2018 and April 2023 was conducted. The depressive and obsessive outcome rating scales used were clinician-rated Montgomery-Åsberg Depression Rating Scale (MADRS), Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Clinical Global Impressions-Severity (CGI-S) and self-rated Depression Anxiety and Stress Scale-21 (DASS-21). Results: Clinician-rated and self-rated mood and general condition improved significantly. MADRS mean score improved from 28.1 (standard deviation [SD] 7.3) to 20.7 (SD 10.1) (P<0.0001) (20.8% response rate/17% remission rate). CGI-S mean 4.6 (SD 0.8) improved to 3.3 (SD 1.2) (P<0.0001). DASS-21 total mean improved from 67.3 (SD 24.6) to 49.6 (SD 28.0) (P<0.0001). Y-BOCS mean score displayed a trend towards improvement from 30.1 (SD 7.5) to 27.2 (SD 6.9) (P=0.799). However, 44.4% of patients with OCD responded with a minimal 20% reduction in baseline Y-BOCS. Moreover, the subgroup of 35.8% of patients with less than 30 rTMS sessions had contributed disproportionately to nonresponse (85.7%). Patients who received rTMS treatment (>30 sessions) had a trend of larger improvement of MADRS score when compared to patients with (≤30 sessions) (9.4 [SD 9.7] versus 3.8 [SD 12.3] [P=0.078]). Conclusion: Response and remission rates for MDD and OCD suggest patients have a good response to rTMS treatment. Dosing longer rTMS sessions after an acute course helps to maximise effectiveness. Further research to determine predictors of outcome and characterise clinical features of late responders to target treatment more effectively is recommended.

Off-Label Use of Naltrexone in Pica and Other Compulsive Behaviors: A Report of Two Cases.

Pica is known to the medical community as an eating disorder in which individuals may ingest non-food items due to a nutritional deficiency and cause unintentional physical harm to themselves. This article discusses the cases of children with pica in addition to other comorbidities such as trichotillomania, depression, autism, and anxiety. Both patients were trialed on typical first-line treatments to address pica symptoms, including antidepressants, psychotherapy, and neurology consults, which were ineffective in treating pica symptoms. The introduction of naltrexone resulted in significant improvements, including decreased pica symptoms and improvements in depression, anxiety, and overall behaviors. These effects of naltrexone were further bolstered by the effects that occurred when both patients discontinued naltrexone for some time.

Advances in Pediatric Obsessive-Compulsive Disorder (OCD) Treatment: A Comprehensive Narrative Review.

Obsessive-compulsive disorder (OCD), characterized by persistent, intrusive thoughts (obsessions) and repetitive behaviors or mental acts (compulsions), can significantly impact a child's daily functioning, academic performance, and overall quality of life. As the prevalence of pediatric OCD continues to rise, there is a critical demand for evidence-based treatments that not only alleviate symptoms but also enhance the quality of life for affected children and adolescents. By identifying gaps in knowledge and suggesting directions for future research, this narrative review contributes to the ongoing discourse on pediatric OCD treatments. Ultimately, the synthesis of evidence aims to enhance our understanding and inform best practices in the compassionate and effective management of OCD in children and adolescents. The aim of this study is to provide a comprehensive overview of current trends and emerging strategies in the treatment of pediatric obsessive-compulsive disorder (OCD) and highlights the significance of tailoring treatment approaches to individual patient needs, considering factors such as symptom severity and treatment response. Concentrating on interventions supported by empirical evidence, the review delves into cognitive-behavioral therapy (CBT), pharmacotherapy, the synergistic effects of these modalities, and inventive therapeutic approaches, all while considering the distinctive developmental aspects pertinent to pediatric populations. We conducted this review by searching for titles in the PubMed database from 2013 to present. Our comprehensive literature review focused on advancements in treating pediatric OCD, using keywords like "Obsessive-compulsive disorder," "Pediatric," "treatment," "CBT," "SSRI," "Pharmacotherapy," and "combination therapy." While both pharmacotherapy and CBT show individual efficacy, the combination of these approaches appears to be more effective, especially for medication non-responders with no prior exposure to CBT, despite some mixed findings. These findings contribute significantly to the ongoing discussion on optimizing combined therapy strategies tailored to the complexities of pediatric OCD.

No significant alteration in white matter microstructure in first-degree relatives of patients with obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is characterized by structural alteration within white matter tissues of cortico-striato-thalamo-cortical, temporal and occipital circuits. However, the presence of microstructural changes in the white matter tracts of unaffected first-degree relatives of patients with OCD as a vulnerability marker remains unclear. Therefore, here, diffusion-tensor magnetic resonance imaging (DTI) data were obtained from 29 first-degree relatives of patients with OCD and 59 healthy controls. We investigated the group differences in FA using whole-brain analysis (DTI analysis). For additional regions of interest (ROI) analysis, we focused on the posterior thalamic radiation and sagittal stratum, shown in recent meta-analysis of patients with OCD. In both whole-brain and ROI analyses, using a strict statistical threshold (family-wise error rate [FWE] corrected p<.05 for whole-brain analyses, and p<.0125 (0.05/4) with Bonferroni correction for ROI analyses), we found no significant group differences in FA. Subtle reductions were observed in the anterior corona radiata, forceps minor, cingulum bundle, and corpus callosum only when a lenient statistical was applied (FWE corrected p<.20). These findings suggest that alterations in the white matter microstructure of first-degree relatives, as potential vulnerability markers for OCD, are likely subtle.

A systematic review of focused ultrasound for psychiatric disorders: current applications, opportunities, and challenges.

OBJECTIVE: Advancements in MRI-guided focused ultrasound (MRgFUS) technology have led to the successful treatment of select movement disorders. Based on the comparative success between ablation and deep brain stimulation, interest arises in focused ultrasound (FUS) as a promising treatment modality for psychiatric illnesses. In this systematic review, the authors examined current applications of FUS for psychiatric conditions and explored its potential opportunities and challenges. METHODS: The authors performed a comprehensive review using the PRISMA guidelines of studies investigating psychiatric applications for FUS. Articles indexed on PubMed between 2014 to 2024 were included. The authors synthesized the psychiatric conditions treated, neural targets, outcomes, study design, and sonication parameters, and they reviewed important considerations for the treatment of psychiatric disorders with FUS. They also discussed active clinical trials in this research domain. RESULTS: Of 250 articles, 10 met the inclusion criteria. Eight articles investigated the clinical, safety, and imaging correlates of MRgFUS in obsessive-compulsive disorder (OCD), whereas 3 examined treatment-resistant depression. Bilateral anterior capsulotomy resulted in a full responder rate of 67% (≥ 35% reduction in the Yale-Brown Obsessive-Compulsive Scale score) and 33% (≥ 50% reduction in the score on the Hamilton Rating Scale for Depression) in OCD and treatment-resistant depression, respectively. Sonications ranged from 8 to 36 with targeted lesional temperatures of 51°C-56°C. Lesions in the anterodorsal aspect of the anterior limb of the internal capsule (ALIC) and increased functional connectivity to the left dorsolateral prefrontal cortex and dorsal anterior cingulate cortex significantly predicted reduction in symptoms among patients with OCD, with decreases in beta-band activity in the frontocentral and temporal regions associated with reductions in depression and anxiety. Treatment of the nucleus accumbens with low-intensity FUS (LIFU) in patients with opioid-use disorders resulted in significant reductions in cue-reactive cravings, lasting up to 90 days. No serious adverse events were reported, including cognitive decline. Side effects were generally mild and transient, consisting of headaches, pin-site swelling, and nausea. Fourteen active clinical trials were identified, primarily targeting depression with LIFU. CONCLUSIONS: Currently, FUS for psychiatric conditions is centered on OCD, with early pilot studies demonstrating promising safety and efficacy. Further research expanding on defining optimal patient selection, study design, intensity, and sonication parameters is warranted, particularly as FUS expands to other psychiatric illnesses and incorporates LIFU paradigms. Ethical considerations such as patient consent and equitable access also remain paramount.

Fighting OCD together: An experimental study of the effectiveness and acceptability of seeking and receiving emotional support for OCD.

Excessive reassurance-seeking in OCD has been linked to the maintenance of OCD, functioning as a type of checking ritual. Current treatments recommend the imposition of the extinction of seeking and providing reassurance; however, this is not well tolerated. Although it has been suggested that the provision of support may provide a more helpful alternative, there is no empirical evidence for this. In the present study, 36 participants with OCD engaged with two personalised semi-idiographic scenarios in which they imagined seeking and receiving reassurance and seeking and receiving emotional support in counterbalanced order. The primary outcome measure was anticipated urge to seek reassurance, which was found to significantly decrease in the imagined support condition relative to the imagined reassurance condition regardless of order of presentation. Emotional support was perceived as significantly more acceptable when compared to imagining reassurance in terms of higher ratings of perceived helpfulness in managing emotions, feelings of calmness and closeness, and the sense that they were fighting OCD together. These findings provide preliminary evidence for the value of encouraging the seeking and giving of emotional support as an alternative to reassurance. Implications for clinical work and further research are discussed.

The effectiveness of psychological treatments for obsessive-compulsive disorders: a meta-analysis of randomized controlled trials published over last 30 years.

BACKGROUND: Although numerous studies have examined the effects of psychological treatments for obsessive-compulsive disorder (OCD), their overall effectiveness remains unclear. We aimed to estimate their overall effect by combining all available randomized controlled trials (RCTs) comparing psychological treatments to control groups for OCD. METHODS: We conducted a meta-analysis of 48 RCTs with 55 comparisons published between 1992 and 1 January 2023. The primary outcome was OCD symptom severity, with Hedges' g calculated at post-treatment and follow-up. Random-effects models were employed for all analyses, and the risk of bias was assessed. RESULTS: In general, psychological treatments demonstrated a significantly large effect (g = -1.14; 95% CI [-1.31 to -0.97]; I2 = 72.23%) on reducing OCD symptom severity post-treatment, this finding remained consistent across measures and after excluding outliers, but lost significance in the sensitivity analysis for only studies with low risk of bias. Type of treatment, control group and treatment format were associated with treatment effects. Moreover, more severe baseline OCD symptom severity predicted higher degree of treatment efficacy. No significant differences were observed in dropout rates between the treatment and control groups. Treatment effects lost significance at 3-6 and 6-12 month follow-ups. 87% of RCTs were rated at high risk of bias. CONCLUSIONS: Psychological treatments are effective in reducing OCD symptom severity. However, caution should be exercised when interpreting these results due to the high heterogeneity and risk of bias across RCTs. Future studies with more rigorous methodology are required, as well as studies examining their long-term effectiveness.

A study of clinical correlates and predictors of insight in obsessive compulsive disorder.

Background: Obsessive compulsive disorder (OCD) is a clinically heterogeneous psychiatric disorder in terms of symptom content and insight. Aim: To study the various factors associated with insight in OCD. Materials and Methods: A cross-sectional hospital-based study was conducted among 40 patients with OCD who were evaluated on Yale-Brown Obsessive-Compulsive Scale, Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale, Brown Assessment of Beliefs Scale, Meta-Cognitions Questionnaire, WHOQOL-BREF, and Sheehan Disability Scale. Statistical analysis was done using SPSS version 22. Results: Metacognition, severity of OCD, and associated disability were the significant predictors for insight in patients with OCD. Conclusion: Factors associated with insight in OCD can enhance our understanding in the management of OCD.

Sex-Specific Correlations Between Misophonia Symptoms and ADHD, OCD, and Autism-Related Traits in Adolescent Outpatients.

Introduction: Misophonia, not yet classified within diagnostic manuals, triggers strong emotional, physiological, and behavioural reactions to specific sounds. This study examines its correlations with attention deficient/hyperactivity disorder (ADHD) traits, obsessive-compulsive traits, and autism-related traits in adolescent outpatients with non-psychotic disorders. We hypothesize a positive association between misophonic symptoms and these psychological traits. Methods: This study was conducted at a Turkish psychiatric centre from January to July 2023 in adolescents aged 12-18. Parents completed the Autism Spectrum Quotient-Adolescent (AQ-Adolescent), and Conner's ADHD Parent Rating Scale-48 (CPRS-48), while the adolescent filled out the Misophonic Symptom Checklist (MCL) and Maudsley Obsessive-Compulsive Inventory (MOCI). Using non-parametric statistical tests, the research found associations between the scales, with a total sample size of 348. Results: Females had higher scores on MCL. There is a negative correlation between AQ-Adolescent and MCL, positive correlations between MCL-MOCI and MCL-CPRS-48. In gender specific correlation analysis found that AQ-Adolescent and MCL were negatively correlated, MCL and MOCI were positively correlated in males. MCL, CPRS-48 and MOCI were positively correlated in females. In regression AQ-Adolescent, MOCI and CPRS-48 significantly predicted the levels of MCL. Conclusions: Our study unveils a link between ADHD, obsessive-compulsive symptoms, autistic traits, and misophonic symptoms in adolescent psychiatric outpatients, highlighting sex differences.

Trichobezoars in children - A psychological perspective.

Trichobezoars or hairballs in the gastrointestinal tract occur as a complication of trichotillomania or compulsive hair pulling, and trichophagia, or compulsive eating of hair. The DSM-5 classifies trichotillomania as an obsessive-compulsive spectrum disorder. In this case series of four children with trichobezoar, we present the varied psychopathology that led to the same and discuss the current literature on complex issues underlying trichotillomania.

Association between clinical features and decreased degree centrality and variability in dynamic functional connectivity in the obsessive-compulsive disorder.

Neuroimaging studies have indicated widespread brain structural and functional disruptions in patients with obsessive-compulsive disorder (OCD). However, the underlying mechanism of these changes remains unclear. A total of 45 patients with OCD and 42 healthy controls (HC) were enrolled. The study investigated local degree centrality (DC) abnormalities and employed abnormal regions of DC as seeds to investigate variability in dynamic functional connectivity (dFC) in the whole brain using a sliding window approach to analyze resting-state functional magnetic resonance imaging. The relationship between abnormal DC and dFC as well as the clinical features of OCD were examined using correlation analysis. Our findings suggested decreased DC in the bilateral thalamus, bilateral precuneus, and bilateral cuneus in OCD patients and a nominally negative correlation between the DC value in the thalamus and illness severity measured using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). In addition, seed-based dFC analysis showed that compared to measurements in the HC, the patients had decreased dFC variability between the left thalamus and the left cuneus and right lingual gyrus, and between the bilateral cuneus and bilateral postcentral gyrus, and a nominally positive correlation between the duration of illness and dFC variability between the left cuneus and left postcentral gyrus. These results indicated that OCD patients had decreased hub importance in the bilateral thalamus and cuneus throughout the entire brain. This reduction was associated with impaired coupling with dynamic function in the visual cortex and sensorimotor network and provided novel insights into the neurophysiological mechanisms underlying OCD.