There is accumulating evidence for the role of fronto-striatal and associated circuits in obsessive-compulsive disorder (OCD) but limited and conflicting data on alterations in cortical thickness.
To ...investigate alterations in cortical thickness and subcortical volume in OCD.
In total, 412 patients with OCD and 368 healthy adults underwent magnetic resonance imaging scans. Between-group analysis of covariance of cortical thickness and subcortical volumes was performed and regression analyses undertaken.
Significantly decreased cortical thickness was found in the OCD group compared with controls in the superior and inferior frontal, precentral, posterior cingulate, middle temporal, inferior parietal and precuneus gyri. There was also a group × age interaction in the parietal cortex, with increased thinning with age in the OCD group relative to controls.
Our findings are partially consistent with earlier work, suggesting that group differences in grey matter volume and cortical thickness could relate to the same underlying pathology of OCD. They partially support a frontostriatal model of OCD, but also suggest that limbic, temporal and parietal regions play a role in the pathophysiology of the disorder. The group × age interaction effects may be the result of altered neuroplasticity.
Obsessive-compulsive disorder (OCD) is a common psychiatric disorder with a lifetime prevalence of 2-3%. Recently, brain activity in the resting state is gathering attention for exploring altered ...functional connectivity in psychiatric disorders. Although previous resting-state functional magnetic resonance imaging studies investigated the neurobiological abnormalities of patients with OCD, there are concerns that should be addressed. One concern is the validity of the hypothesis employed. Most studies used seed-based analysis of the fronto-striatal circuit, despite the potential for abnormalities in other regions. A hypothesis-free study is a promising approach in such a case, while it requires researchers to handle a dataset with large dimensions. Another concern is the reliability of biomarkers derived from a single dataset, which may be influenced by cohort-specific features. Here, our machine learning algorithm identified an OCD biomarker that achieves high accuracy for an internal dataset (AUC = 0.81; N = 108) and demonstrates generalizability to an external dataset (AUC = 0.70; N = 28). Our biomarker was unaffected by medication status, and the functional networks contributing to the biomarker were distributed widely, including the frontoparietal and default mode networks. Our biomarker has the potential to deepen our understanding of OCD and to be applied clinically.
Abstract There is increasing evidence of white matter abnormalities in patients with obsessive-compulsive disorder (OCD). The results of previous diffusion tensor imaging (DTI) studies, however, are ...inconsistent. Reasons for this inconsistency may include methodological issues such as misregistration, the differences in smoothing voxel-based morphometry style analysis or both. To date there are no DTI studies with tract-based spatial statistics (TBSS) which overcome these issues. In addition, previous studies had few drug-free patients, thus potentially reducing their power and obscuring their findings. Therefore, the aim of present study was to investigate white matter abnormalities using DTI and TBSS analysis in a large sample of drug-free patients with OCD. Thirty drug-free patients with OCD and 30 healthy controls underwent DTI. Fourteen of 30 patients were drug naïve. Voxel-wise group comparison of white matter fractional anisotropy (FA) was performed using TBSS. Compared to healthy volunteers, OCD patients had statistically less FA in the anterior body of corpus callosum (CC) ( p < .05, corrected). They also had a trend for a lower FA in the large portion of CC, the right cingulum, and the left anterior limb of internal capsule (ALIC). There were no areas of the brain with significantly higher FA. This is the first study that has investigated white matter abnormalities in non-medicated patients with OCD using DTI and TBSS analyses. Microstructural white matter abnormalities in the CC, the cingulum, and the ALIC might be involved in the pathophysiology of OCD.
Abstract Dysfunction of the fronto-striato-thalamic circuit routing through the orbitofrontal cortex (OFC) is thought to play the main role in the pathophysiology of obsessive-compulsive disorder ...(OCD). Repetitious stimulation of the OFC–ventral striatum (VS) projections in mice has been shown to increase the firing of the postsynaptic VS cells and the frequency of OCD-like symptoms. Moreover, increased functional connectivity (FC) between the OFC and the VS has been reported in patients with OCD. While FC is a synchronous, non-directed correlation, the directed influence between these brain regions remains unclear in patients with OCD. We obtained resting state functional magnetic resonance imaging scans from 37 non-medicated patients with OCD and 38 matched healthy volunteers, and calculated bivariative voxel-wise Granger Causality (GC) to and from three striatal regions of interest (ROI) using a blind deconvolution procedure. Additionally, we conducted multivariative GC analysis to determine if the effect revealed by the bivariative voxel-wise GCA is mediated by another seed ROI. We found a significant hyper-influence of the OFC over the VS of subjects with OCD ( p <.05, corrected). Multivariative GC analysis confirmed this effect ( p <.05, corrected) and that it was not mediated by another brain area within the striatum. This is the first study investigating the directed influence of the fronto-striato-thalamic loop in non-medicated patients with OCD. We confirmed the hyperactive connection from the OFC to the VS that is consistent with previous animal studies. These findings provide evidence for the more detailed pathophysiology of OCD.
Introduction: Occupation-based practice (OBP) is seldom performed for people with severe acute cerebrovascular accidents (CVA). This study aimed to explore the conditions and situations in which ...occupational therapists (OTs) provide OBP to patients with severe acute CVA. Methods: Semi-structured interviews with eight OTs were conducted to determine OBP for patients with severe acute CVA. The participants were OTs who had conducted OBP for patients with CVA in an acute care setting. Data were analyzed using inductive analysis. The procedures were: (i) to create verbatim records, (ii) to separate the verbatim records by context and to code while comparing the differences and commonalities of each code, (iii) to create subcategories, and (iv) to create categories by grouping together the subcategories with concepts that have similarities.Results: The participants (OTs) reported that they have performed OBP for patients with severe acute CVA patients when (1) environments are available to perform occupations, (2) OTs establish good quality teamwork with multi-disciplinary professionals, (3) OTs emphasize patient-centered practice, (4) patients express their wishes to do occupations, (5) patients and families are getting to ready to resume occupation, (6) patients' occupations are actionable and meaningful.Conclusion: The OTs' belief, the supportive environment, the client and family oriented toward occupations, and the identification of actionable and meaningful occupations were critical for the OTs to implement OBP for the severe acute CVA patients. These results could provide OTs with insights for promoting OBP in acute settings, especially working with patients with severe acute CVA.
Introduction: Peer support programs are mainly studied by hospitals and medical professionals, and further research is needed on their impact on quality of life (QOL). The purpose of this study was ...to investigate the type of community-based peer support program that is effective for improving the QOL of cancer survivors. Method: A systematic review was performed using the following procedures: (1) randomized controlled trials aimed at improving QOL were searched from PubMed and Igaku Chuo Zasshi, (2) papers that met the inclusion criteria were selected, and (3) the papers were assessed for quality by using the revised Cochrane risk-of-bias tool for randomized trials.Results: Results showed that four studies met the eligibility criteria, and three of them showed statistically significant improvements in QOL. The peers instructed in programs were breast cancer survivors who had been diagnosed one to three years earlier. Furthermore, peers received special training for approximately eight hours per session for a total of two to seven days before providing support to the participants.Conclusion: Few programs have been fully applied in Japan. In terms of program effectiveness and risk of bias, programs that include obtaining support and managing activities that affect mood may be effective. Furthermore, the importance of taking enough time to help cancer survivors trust each other and provide support according to the patient's wishes and available community resources was demonstrated.
Fronto-striatal circuits are hypothesized to be involved in the pathophysiology of obsessive-compulsive disorder (OCD). Within this circuitry, ventral frontal regions project fibers to the ventral ...striatum (VS) and dorsal frontal regions to the dorsal striatum. Resting state fMRI research has shown higher functional connectivity between the orbitofrontal cortex (OFC) and the dorsal part of the VS in OCD patients compared to healthy controls (HC). Therefore, we hypothesized that in OCD the OFC predominantly project fibers to the more dorsal part of the VS, and that the structural connectivity between the OFC and VS is higher compared to HC. A total of 20 non-medicated OCD patients and 20 HC underwent diffusion-weighted imaging. Connectivity-based parcellation analyses were performed with the striatum as seed region and the OFC, dorsolateral prefrontal cortex, and dorsal anterior cingulate cortex as target regions. Obtained connectivity maps for each frontal region of interest (ROI) were normalized into standard space, and Z-component (dorsal-ventral) coordinate of center-of-gravity (COG) were compared between two groups. Probabilistic tractography was performed to investigate diffusion indices of fibers between the striatum and frontal ROIs. COG Z-component coordinates of connectivity maps for OFC ROI were located in the more dorsal part of the VS in OCD patients compared to HC. Fractional anisotropy of fibers between the OFC and the striatum was higher in OCD patients compared to HC. Part of the pathophysiology of OCD might be understood by altered topography and structural connectivity of fibers between the OFC and the striatum.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In recent years, a large number of studies have investigated obsessive-compulsive disorder (OCD) using diffusion-weighted images (DWIs) and have reported microstructural abnormalities in various ...regions, mainly the corpus callosum and cingulum. In the present study, we aimed to detect microstructural changes in the white matter using whole-brain tractography.
We obtained MRI data from 25 adult non-medicated OCD patients and 27 healthy controls. DWI data from MRI scans were analyzed by the automated probabilistic tractography method referred to as TRActs Constrained by UnderLying Anatomy (TRACULA). We investigated diffusivity parameters: fractional anisotropy, radial diffusivity (RD), axial diffusivity, and mean diffusivity in 18 major white matter tracts and examined indices to know which measurements in which fibers can predict the diagnosis of OCD.
Compared to healthy controls, OCD patients had significantly increased RD in the forceps major and a reduction of RD in the right cingulum angular (infracallosal) bundle. There was no correlation between these values and the clinical features.
We found RD alterations in the forceps major and the right cingulum angular (infracallosal) bundle, which might be associated with myelination changes in the temporal and occipital regions in OCD. Our results suggest that the pathogenesis of OCD may include abonormality of myelination status in not only the fronto-striato-thalamic circuit but also the posterior and temporal regions.
Background. Many occupational therapists face the challenge of helping clients with dementia to select and perform meaningful occupations, which may be difficult due to cognitive impairment. ...Understanding tacit knowledge of well-experienced occupational therapists could positively affect occupational therapy practice for clients with dementia. Objectives of Study. To explore the observations of experienced occupational therapists when evaluating the effects of activities in clients with dementia. Methods. Ten occupational therapists with over 10 years of clinical experience participated in this qualitative study. In-depth interviews were conducted to ask the question, “What do you observe in clients with dementia when you assess the effectiveness of activities among these clients?” Findings. From 47 cases, we found five major themes and 18 subthemes. Main themes were “engaging activity,” “emotional expression during activity,” “verbal expression during activity,” “social interaction through activity,” and “something obtained as outcome of activity.” Relevance to Clinical Practice. The 18 subthemes could be used as viewpoints to observe engagements of activity in clients with dementia. Limitations and Recommendations for Further Research. Future studies could examine which viewpoints were utilized for each type of activity and/or severity of dementia as this was not investigated in the current study.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ