Exposure and response prevention is an effective treatment for obsessive-compulsive disorder (OCD), but it is unclear how symptom reduction is related to changes in the brain. We aimed to determine ...the effects of a 4-day concentrated exposure and response prevention program (Bergen 4-day treatment) on the static and dynamic functional connectome in patients with OCD.
Thirty-four patients with OCD (25 unmedicated) underwent resting-state functional magnetic resonance imaging the day before the Bergen 4-day treatment, and 28 (21 unmedicated) were rescanned after 1 week. Twenty-eight healthy control subjects were also scanned for baseline comparisons and 19 of them were rescanned after 1 week. Static and dynamic graph measures were quantified to determine network topology at the global, subnetwork, and regional levels (including efficiency, clustering, between-subnetwork connectivity, and node flexibility in module allegiance). The Yale-Brown Obsessive Compulsive Scale was used to measure symptom severity.
Twenty-four patients (86%) responded to treatment. We found significant group × time effects in frontoparietal-limbic connectivity (ηp2 = 0.19, p = .03) and flexibility of the right subgenual anterior cingulate cortex (ηp2 = 0.18, p = .03), where, in both cases, unmedicated patients showed significant decreases while healthy control subjects showed no significant changes. Healthy control subjects showed increases in global and subnetwork efficiency and clustering coefficient, particularly in the somatomotor subnetwork.
Concentrated exposure and response prevention in unmedicated patients with OCD leads to decreased connectivity between the frontoparietal and limbic subnetworks and less flexibility of the connectivity of the subgenual anterior cingulate cortex, suggesting a more independent and stable network topology. This may represent less limbic interference on cognitive control subnetworks after treatment.
Objective Obsessive-compulsive disorder (OCD) is a common neuropsychiatric disorder with moderate genetic influences and white matter (WM) abnormalities in frontal-striatal and limbic regions. ...Inconsistencies in reported WM results from diffusion tensor imaging (DTI) studies can be explained, at least partly, by medication use and between-group differences in disease profile and stage. We used a family design aiming to establish whether WM abnormalities, if present in un-medicated OCD patients, also exist in their unaffected siblings. Method Forty-four un-medicated OCD patients, 15 of their unaffected siblings and 37 healthy controls (HC) underwent DTI using a 3-Tesla MRI-scanner. Data analysis was done using tract-based spatial statistics (TBSS). Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) values were compared within seven skeletonised regions of interest (ROIs), i.e., corpus callosum (CC), bilateral cingulum bundle (CB), bilateral inferior longitudinal fasciculus/frontal-occipital fasciculus (ILF/FOF) and bilateral superior longitudinal fasciculus (SLF). Results Un-medicated OCD patients, compared with HC, had significantly lower FA in the left CB. FA was trend-significantly lower in all other ROIs, except for the CC. Significant three-group differences in FA (and in RD at trend-significant level) were observed in the left CB, with the unaffected siblings representing an intermediate group between OCD patients and HC. Conclusions OCD patients showed lower FA in the left CB, partly driven by trend-significantly higher values in RD. Since the unaffected siblings were found to be an intermediate group between OCD patients and HC, this WM alteration may be considered an endophenotype for OCD.
Functional neuroimaging endophenotypes of obsessive-compulsive disorder (OCD) have been suggested during executive tasks. The purpose of this study was to investigate whether behavioral and neural ...responses during emotion processing and regulation also represent an endophenotype of OCD.
Forty-three unmedicated adult OCD patients, 19 of their unaffected siblings, and 38 healthy control participants underwent 3T functional magnetic resonance imaging during an emotion regulation task including neutral, fear-inducing, and OCD-related visual stimuli. Stimuli were processed during natural appraisal and during cognitive reappraisal, and distress ratings were collected after each picture. We performed between-group comparisons on task behavior and brain activation in regions of interest during emotion provocation and regulation.
Siblings reported similar distress as healthy control participants during provocation, and significantly less than patients. There was no significant three-group difference in activation during fear provocation or regulation. Three-group comparisons showed that patients had higher amygdala and dorsomedial prefrontal cortex activation during OCD-related emotion provocation and regulation, respectively, while siblings were intermediate between patients and control participants but not significantly different from either. Siblings showed higher left temporo-occipital activation (compared with both healthy control participants and patients) and higher frontolimbic connectivity (compared with patients) during OCD-related regulation.
Unaffected siblings do not show the same distress and amygdala activation during emotional provocation as OCD patients. Siblings show distinct activation in a temporo-occipital region, possibly related to compensatory cognitive control. This suggests that emotion regulation is not a strong endophenotype for OCD. When replicated, this contributes to our understanding of familial risk and resilience for OCD.
Abstract Obsessive-compulsive disorder (OCD) is a relatively common psychiatric disorder characterized by intrusive thoughts and behaviors that dominate daily living, like an itch patients cannot ...ignore. Deficits in executive functioning are common in OCD and are thought to be related to dysfunctional frontal-striatal systems. One of those executive functions is cognitive flexibility, defined as the ability to rapidly switch response strategies following changes in task-relevant information. The temporal stability of cognitive flexibility impairments in OCD has been incompletely investigated since previous studies have suggested both state and trait dependency. In this study, 16 OCD patients performed a functional magnetic resonance imaging version of a task-switching paradigm twice, intervened by a follow-up period of on average 6 months. Results show that functional abnormalities in the dorsal frontal-striatal circuit and anterior cingulate cortex at baseline normalized at follow-up. This change in the recruitment of task-related brain circuits correlated with change in disease severity. These results support the view that the imbalance between the dorsal and ventral frontal-striatal circuits is at least partly state-dependent, and is associated with a reduction in symptom severity.
Abstract Objectives Reversal learning (RL) is impaired in obsessive-compulsive disorder (OCD) as well as in major depressive disorder (MDD). It is yet unknown to what extent pathophysiological ...mechanisms are state-dependent. Methods Neural activation patterns during RL were measured using event-related functional magnetic resonance imaging (fMRI) reversal learning in patients with OCD (N=18) and MDD (N=15). A naturalistic follow-up design enabled investigation of the relationship between changes in clinical state, task performance and task-related neural activation over time. Results During follow-up, disease severity decreased significantly in both groups. Whereas task speed improved trend-significantly, task accuracy was unchanged. Task-related dorsal frontal-striatal activation decreased at follow-up in MDD, but increased in OCD. In both groups, symptom improvement was associated with reward-related changes in neural activation in the putamen and the orbitofrontal cortex. Conclusions In both OCD and MDD, symptom reduction over time was associated with partial normalization of task-related activation patterns in brain regions. Whereas in OCD this normalisation was characterized by increased recruitment of previously hypoactive frontal-striatal brain regions (i.e. dorsal frontal-striatal failure), in MDD previously hyperactive brain regions (frontal-striatal inefficiency), were recruited less after recovery. These results show that in both disorders frontal-striatal dysfunction is at least partly state-dependent.
The recently developed Social Exclusion Index for Health Surveys (SEI-HS) revealed particularly strong social exclusion in non-Western immigrant groups compared to the native Dutch population. To ...qualify such results, cross-cultural validation of the SEI-HS in non-Western immigrant groups is called for. A sequential explanatory mixed methods design was used, employing quantitative data from the Netherlands Public Health Monitor along with qualitative interviews. Data from 1,803 adults aged 19 years or older of Surinamese, 1,009 of Moroccan and 1,164 of Turkish background and 19,318 native Dutch living in the four largest cities in the Netherlands were used to test the factorial structure of the SEI-HS and differential item functioning across immigrant groups. Additionally, 52 respondents with a high score on the SEI-HS and from different background were interviewed on the item content of the SEI-HS and subjective feelings of exclusion. For each SEI-HS item the semantic, conceptual and contextual connotations were coded and compared between the immigrant groups and native Dutch. High levels of social exclusion were found in 20.0% of the urban population of Surinamese origin, 20.9% of Moroccan, 28.7% of Turkish and 4.2% of native Dutch origin. The 4-factor structure of the SEI-HS was confirmed in all three immigrant groups. None of the items demonstrated substantial differential item functioning in relation to immigration background. The interviews uncovered some methodological shortcomings, but these did not substantially impact the observed excess of social exclusion in immigrant groups. The present study provides evidence in support of the validity of the SEI-HS in adults of Surinamese, Moroccan and Turkish background and confirms the major social exclusion of these immigrant groups in the main cities in the Netherlands. Policy measures to enhance social inclusion and reduce exclusion are urgently needed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objective
Neuroimaging studies of obsessive‐compulsive disorder (OCD) patients have highlighted the important role of deep gray matter structures. Less work has however focused on subcortical shape ...in OCD patients.
Methods
Here we pooled brain MRI scans from 412 OCD patients and 368 controls to perform a meta‐analysis utilizing the ENIGMA‐Shape protocol. In addition, we investigated modulating effects of medication status, comorbid anxiety or depression, and disease duration on subcortical shape.
Results
There was no significant difference in shape thickness or surface area between OCD patients and healthy controls. For the subgroup analyses, OCD patients with comorbid depression or anxiety had lower thickness of the hippocampus and caudate nucleus and higher thickness of the putamen and pallidum compared to controls. OCD patients with comorbid depression had lower shape surface area in the thalamus, caudate nucleus, putamen, hippocampus, and nucleus accumbens and higher shape surface area in the pallidum. OCD patients with comorbid anxiety had lower shape surface area in the putamen and the left caudate nucleus and higher shape surface area in the pallidum and the right caudate nucleus. Further, OCD patients on medication had lower shape thickness of the putamen, thalamus, and hippocampus and higher thickness of the pallidum and caudate nucleus, as well as lower shape surface area in the hippocampus and amygdala and higher surface area in the putamen, pallidum, and caudate nucleus compared to controls. There were no significant differences between OCD patients without co‐morbid anxiety and/or depression and healthy controls on shape measures. In addition, there were also no significant differences between OCD patients not using medication and healthy controls.
Conclusions
The findings here are partly consistent with prior work on brain volumes in OCD, insofar as they emphasize that alterations in subcortical brain morphology are associated with comorbidity and medication status. Further work is needed to understand the biological processes contributing to subcortical shape.
There is a paucity of literature on subcortical shape in OCD patients. In this multi‐site meta‐analysis there was no significant difference in shape between OCD patients and controls, however abnormalities in both shape thickness and surface area were found for medicated OCD patients with comorbid anxiety and depression compared to healthy controls.
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