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1.
Front Psychiatry ; 14: 1227057, 2023.
Article in English | MEDLINE | ID: mdl-37840793

ABSTRACT

Background: Patients with obsessive-compulsive disorder (OCD) have deficits in decision-making in the Iowa Gambling Task (IGT). However, no study has investigated the parameters of the prospect valence learning (PVL) model in the IGT for OCD. Aims: This study aimed to investigate deficits in decision-making in OCD using the PVL model and identify whether the parameters of the PVL model were associated with obsessive-compulsive severity. Methods: Forty-seven medication-free patients with OCD were compared with 47 healthy controls (HCs). Decision-making was measured using the total net and block net scores of the IGT. A PVL model with a decay-reinforcement learning rule (PVL-DecayRI) was used to investigate the parameters of the model. Correlation analysis was conducted between each parameter of the PVL-DecayRL and obsessive-compulsive symptoms. Results: The total net score of patients with OCD was significantly lower than that of the HCs. The block net scores of the OCD group did not differ across the five blocks, whereas in the HCs, the fifth block net score was significantly higher than the block net scores of the first and second blocks. The values of the recency and response consistency parameters of the PVL-DecayRI in patients with OCD were significantly lower than those in HCs. The recency parameter positively correlated with the Y-BOCS obsessive score. Meanwhile, there was no correlation between consistency parameter values and symptom severity in OCD. Conclusion: Our detailed analysis of the decision-making deficit in OCD suggests that the most recent outcome has a small influence on the expectancy of prospect valence, as indicated by the lower recency parameter, and is characterized by more impulsive choices, as indicated by the lower consistency parameter.

2.
Psychiatry Res Neuroimaging ; 334: 111669, 2023 09.
Article in English | MEDLINE | ID: mdl-37393805

ABSTRACT

Recent evidence suggests that broad brain regions, not limited to the fronto-striato-thalamo-cortical circuit, play an important role in motor response inhibition. However, it is still unclear which specific key brain region is responsible for impaired motor response inhibition observed in obsessive-compulsive disorder (OCD). We calculated the fractional amplitude of low-frequency fluctuations (fALFF) and measured response inhibition ability using the stop-signal task in 41 medication-free patients with OCD and 49 healthy control (HC) participants. We explored the brain region that shows different association between the fALFF and the ability of motor response inhibition. Significant differences in fALFF associated with the ability of motor response inhibition were identified in dorsal posterior cingulate cortex (PCC). There was a positive correlation between increased fALFF in the dorsal PCC and impaired motor response inhibition in OCD. In the HC group, there was a negative correlation between the two variables. Our results suggest that the magnitude of resting-state blood oxygen level-dependent oscillation of the dorsal PCC is a key brain region for the underlying mechanisms of impaired motor response inhibition in OCD. Future studies should examine whether this characteristic of dorsal PCC affects other large-scale networks responsible for motor response inhibition of OCD.


Subject(s)
Gyrus Cinguli , Obsessive-Compulsive Disorder , Humans , Gyrus Cinguli/diagnostic imaging , Magnetic Resonance Imaging/methods , Brain , Brain Mapping/methods , Obsessive-Compulsive Disorder/diagnostic imaging
3.
Front Psychiatry ; 13: 836965, 2022.
Article in English | MEDLINE | ID: mdl-35633792

ABSTRACT

Background: Symptoms of obsessive-compulsive disorder (OCD) have been conceptualized as manifestations of decision-making deficits. Patients with OCD exhibit impairment during the decision-making process, as assessed by the Iowa Gambling Task (IGT). This impairment is independent of clinical severity and disease progression. However, the association between the decision-making deficit and resting-state brain activity of patients with OCD has not been examined. Methods: Fifty unmedicated patients with OCD and 55 matched control subjects completed IGT. Resting-state brain activity was examined using the fractional amplitude of low-frequency fluctuations (fALFFs). fALFF analysis focused on the slow-4 and 5 bands. Group comparisons were performed to determine the association between IGT performance and fALFFs. Results: There was a significant group difference in the association between the IGT total net score and slow-4 fALFFs in the left putamen (voxel height threshold of p < 0.001; cluster size threshold of p < 0.05; family wise error-corrected). Higher putamen slow-4 fALFFs were correlated with lower IGT scores for OCD patients (r = -0.485; p < 0.0005) and higher IGT scores for control subjects (r = 0.402; p < 0.005). There was no group difference in the association between the IGT total net score and slow-5 fALFFs. Conclusions: These findings in unmedicated patients demonstrate the importance of resting-state putamen activity for decision-making deficit associated with OCD, as measured by IGT. The inverse correlation may be explained by the hypersensitive response of the putamen in patients with OCD.

4.
Article in English | MEDLINE | ID: mdl-35108587

ABSTRACT

Background It is gradually becoming clear that obsessive-compulsive disorder (OCD) patients have aberrant resting-state large-scale intrinsic networks of cingulo-opercular salience (SN), default mode (DMN), and front-parietal network (FPN). However, it remains unknown whether unaffected first-degree relatives of OCD patients have these alterations as a vulnerability marker to the disorder. Methods We performed resting-state functional magnetic resonance imaging (rsfMRI) scans of 47 medication-free OCD patients, 21 unaffected healthy first-degree relatives of OCD patients, and 62 healthy control (HC) participants. We explored differences between the three groups in the functional connectivity from SN (seeds: anterior-insula (AI) and dorsal anterior cingulate cortex (dACC)), DMN (seeds: medial prefrontal cortex (MPFC) and posterior parietal cortex (PCC)), and FPN (seeds: dorsolateral prefrontal cortex (DLPFC)). Results Compared to HC, both OCD patients and first-degree relatives showed significantly greater functional connectivity between AI and PCC and between DLPFC and the thalamus. Compared to first-degree relatives and HC, OCD patients showed reduced functional connectivity between PCC and DLPFC, and this altered functional connectivity was negatively correlated with anxiety and depressive symptom within OCD group. Conclusions OCD patients and unaffected first-degree relatives of OCD patients showed overlapping alterations in resting state functional connectivity between the regions of SN and DMN and between DLPFC and the thalamus. Our results suggested that alterations between large-scale intrinsic networks and within the dorsal cognitive cortico-striato-thalamo-cortical (CSTC) circuit could represent endophenotype markers of OCD.


Subject(s)
Endophenotypes , Obsessive-Compulsive Disorder , Brain Mapping , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Neural Pathways/diagnostic imaging , Obsessive-Compulsive Disorder/diagnostic imaging , Obsessive-Compulsive Disorder/genetics , Thalamus
5.
J Psychiatr Res ; 148: 1-8, 2022 04.
Article in English | MEDLINE | ID: mdl-35081485

ABSTRACT

Although preliminary neuroimaging research suggests that patients with hoarding disorder (HD) show widespread abnormal task-related activity in the brain, there has been no research on alterations in the white matter tracts in these patients. The aim of this study was to investigate the characteristics of the major white matter tracts in patients with HD. Tract-based spatial statistics were used to search for white matter tract abnormalities throughout the brain in 25 patients with HD and 36 healthy controls. Post hoc analysis of regions of interest was performed to detect correlations with clinical features. Compared with the controls, patients with HD showed decreased fractional anisotropy and increased radial diffusivity in anatomically widespread white matter tracts. Post hoc analysis of regions of interest revealed a significant negative correlation between the severity of hoarding symptoms and fractional anisotropy in the left anterior limb of the internal capsule and a positive correlation between the severity of these symptoms and radial diffusivity in the right anterior thalamic radiation. Patients with HD showed a broad range of alterations in the frontal white matter tracts, including the frontothalamic circuit, frontoparietal network, and frontolimbic pathway. The findings of this study indicate associations between frontal white matter abnormalities related to the severity of hoarding symptoms in HD and the cortical regions involved in cognitive dysfunction. The insights provided would be useful for understanding the neurobiological basis of HD.


Subject(s)
Hoarding Disorder , White Matter , Anisotropy , Brain/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Diffusion Tensor Imaging/methods , Hoarding Disorder/diagnostic imaging , Humans , White Matter/diagnostic imaging
6.
Hum Brain Mapp ; 43(3): 974-984, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34816523

ABSTRACT

Recent evidence suggests that presupplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) play an important role in response inhibition. However, no study has investigated the relationship between these brain networks at resting-state and response inhibition in obsessive-compulsive disorder (OCD). We performed resting-state functional magnetic resonance imaging scans and then measured the response inhibition of 41 medication-free OCD patients and 49 healthy control (HC) participants by using the stop-signal task outside the scanner. We explored the differences between OCD and HC groups in the functional connectivity of pre-SMA and IFG associated with the ability of motor response inhibition. OCD patients showed a longer stop-signal reaction time (SSRT). Compared to HC, OCD patients exhibit different associations between the ability of motor response inhibition and the functional connectivity between pre-SMA and IFG, inferior parietal lobule, dorsal anterior cingulate cortex, insula, and anterior prefrontal cortex. Additional analysis to investigate the functional connectivity difference from the seed ROIs to the whole brain voxels revealed that, compared to HC, OCD exhibited greater functional connectivity between pre-SMA and IFG. Also, this functional connectivity was positively correlated with the SSRT score. These results provide additional insight into the characteristics of the resting-state functional connectivity of the regions belonging to the cortico-striato-thalamo-cortical circuit and the cingulo-opercular salience network, underlying the impaired motor response inhibition of OCD. In particular, we emphasize the importance of altered functional connectivity between pre-SMA and IFG for the pathophysiology of motor response inhibition in OCD.


Subject(s)
Cerebral Cortex/physiopathology , Connectome , Corpus Striatum/physiopathology , Inhibition, Psychological , Motor Activity/physiology , Motor Cortex/physiopathology , Nerve Net/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Thalamus/physiopathology , Adult , Cerebral Cortex/diagnostic imaging , Corpus Striatum/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Motor Cortex/diagnostic imaging , Nerve Net/diagnostic imaging , Obsessive-Compulsive Disorder/diagnostic imaging , Thalamus/diagnostic imaging , Young Adult
7.
Front Psychiatry ; 12: 659616, 2021.
Article in English | MEDLINE | ID: mdl-33967861

ABSTRACT

Background: Although abnormality of cerebellar-cerebral functional connectivity at rest in obsessive-compulsive disorder (OCD) has been hypothesized, only a few studies have investigated the neural mechanism. To verify the findings of previous studies, a large sample of patients with OCD was studied because OCD shows possible heterogeneity. Methods: Forty-seven medication-free patients with OCD and 62 healthy controls (HCs) underwent resting-state functional magnetic imaging scans. Seed-based connectivity was examined to investigate differences in cerebellar-cerebral functional connectivity in OCD patients compared with HCs. Correlations between functional connectivity and the severity of obsessive-compulsive symptoms were analyzed. Results: In OCD, we found significantly increased functional connectivity between the right lobule VI and the left precuneus, which is a component of the default mode network (DMN), compared to HCs. However, there was no correlation between the connectivity of the right lobule VI-left precuneus and obsessive-compulsive severity. Conclusions: These findings suggest that altered functional connectivity between the cerebellum and DMN might cause changes in intrinsic large-scale brain networks related to the traits of OCD.

8.
Front Psychiatry ; 11: 561266, 2020.
Article in English | MEDLINE | ID: mdl-33343411

ABSTRACT

Not a few patients with obsessive-compulsive disorder (OCD) have experienced events that affected the onset. The onset of OCD is not limited to the original meaning of trauma; rather, traumatic experiences such as unexpected exposure to contaminants or various stressful life events often cause the onset of OCD. It would be useful to understand the experiences surrounding the onset, including stressful life events and traumatic experiences, for comprehension of the pathophysiology of OCD. In the present study, we investigated the onset conditions of 281 patients with OCD and compared clinical characteristics among groups with or without stressful life events including traumatic experiences. As a result, 172 (61.2%) participants had experienced various stressful life events, and 98 (34%) participants had had traumatic experiences before the onset. Furthermore, the participants who had had stressful life events showed more contamination/fear symptoms compared with those without such life events. Meanwhile, the patients who had had specific traumatic experiences showed a tendency toward hoarding obsessions. To comprehend the pathophysiology of OCD, it is important to understand the stressful life events that precede its onset.

9.
Heliyon ; 6(3): e03527, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32181397

ABSTRACT

Previous studies have reported clinical characteristics of hoarding disorder (HD), such as early onset, a chronic course, familiality, high unmarried rate, and high rates of comorbidities. However, clinical research targeting Japanese HD patients has been very limited. As a result, there is a low recognition of HD in Japan, leading to insufficient evaluation and treatment of Japanese HD patients. The aim of the current study was to delineate the clinical characteristics of Japanese HD patients. Thirty HD patients, 20 obsessive-compulsive disorder (OCD) patients, and 21 normal controls (NC) were targeted in this study. The HD group had a tendency toward higher familiality, earlier onset, and longer disease duration compared to the OCD group. In addition, the HD group showed a significantly higher unmarried rate than the NC group. The top two comorbidities in the HD group were major depressive disorder (56.7%) and attention-deficit/hyperactivity disorder (26.7%). The HD group had significantly higher scores on hoarding rating scales and lower scores on the Global Assessment of Functioning Scale than the other two groups. The current study showed a clinical trend in Japanese HD patients similar to previous studies in various countries, suggesting that HD may be a universal disease with consistent clinical symptoms.

10.
Neuroimage Clin ; 24: 102004, 2019.
Article in English | MEDLINE | ID: mdl-31622840

ABSTRACT

BACKGROUND: Impaired cognitive flexibility has been implicated in the genetic basis of obsessive-compulsive disorder (OCD). Recent endophenotype studies of OCD showed neural inefficiency in the cognitive control network and interference by the limbic network of the cognitive control network. Exploring the relationship between the functional brain network and impaired cognitive flexibility may provide novel information about the neurobiological basis of OCD. METHODS: We obtained resting-state functional magnetic resonance imaging (rsfMRI) scans and measured the cognitive flexibility of 37 medication-free OCD patients and 40 healthy control (HC) participants using the Wisconsin Card Sorting Test (WCST). We explored the difference between OCD and HC groups in the functional brain network related to impaired cognitive flexibility from the amygdala and dorsal striatal regions of interest (ROIs) by using a seed-based approach. RESULTS: Significant differences between the OCD and HC groups were identified in the resting state functional network from the dorsal caudate. Increased functional connectivity from the dorsal caudate to the dorsal anterior cingulate cortex (dACC) and anterior insula (AI) was associated with poorer cognitive flexibility in the OCD group, but better cognitive flexibility in the HC group. CONCLUSIONS: These results provide evidence that the impaired cognitive flexibility of OCD may be associated with dysfunctions of the brain network from the dorsal caudate (DC) to important nodes of the salience network. Our results extend the neuropsychological model of OCD by showing intrinsically different associations between OCD and HC in functional network and cognitive flexibility.


Subject(s)
Caudate Nucleus/physiopathology , Cerebral Cortex/physiopathology , Cognitive Dysfunction/physiopathology , Connectome/methods , Executive Function/physiology , Nerve Net/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Adult , Caudate Nucleus/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Female , Gyrus Cinguli/diagnostic imaging , Gyrus Cinguli/physiopathology , Humans , Magnetic Resonance Imaging , Male , Nerve Net/diagnostic imaging , Obsessive-Compulsive Disorder/complications , Obsessive-Compulsive Disorder/diagnostic imaging
11.
PLoS One ; 13(7): e0200814, 2018.
Article in English | MEDLINE | ID: mdl-30011337

ABSTRACT

BACKGROUND: Hoarding disorder (HD) is a disease concept newly presented in DSM-5. As far as we know, no studies have examined the structural changes relevant to hoarding by applying the diagnostic criteria of HD in DSM-5. In the present study, we aimed to find abnormalities in gray matter (GM) structures of patients with HD. METHODS: Seventeen patients who met the DSM-5 criteria for HD, 17 obsessive-compulsive disorder (OCD) patients, and 17 healthy controls (HCs) participated in this study. All participants underwent MRI scanning of the brain by a 3.0-Tesla MRI scanner. In a voxel-based morphometric procedure, preprocessed GM structural images were used to compare the three groups. Thereafter we investigated the correlation between the clinical data (age of onset, symptomatic severity) and GM volume. RESULTS: The HD group showed a significantly increased GM volume compared to the OCD and healthy control groups (p<0.05) in both Brodmann area (BA)10 and BA11. There was no significant difference between OCD and healthy control groups. No significant correlation between the clinical data including age of onset, symptom severity score, and GM volume was observed in HD and OCD groups. CONCLUSIONS: The results might help to explain the inconsistency of previous studies. As with OCD, HD is considered to have cognitive dysfunction as its basis. This result is convincing after considering the clinical features of HD and suggested that structural abnormalities in the prefrontal regions might relate to the pathophysiology of HD.


Subject(s)
Brain/diagnostic imaging , Gray Matter/diagnostic imaging , Gray Matter/physiopathology , Hoarding Disorder/diagnostic imaging , Hoarding Disorder/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Adult , Age of Onset , Brain Mapping , Case-Control Studies , Female , Humans , Image Processing, Computer-Assisted , Linear Models , Magnetic Resonance Imaging , Male , Middle Aged , Obsessive-Compulsive Disorder/diagnostic imaging
12.
Seishin Shinkeigaku Zasshi ; 117(7): 505-18, 2015.
Article in Japanese | MEDLINE | ID: mdl-26552314

ABSTRACT

This article describes the background and recent changes in French forensic mental health. The literature suggests that three law reforms have been crucial to changes in the mental health system. First, the Penal Code of 1992 redefined the provisions of criminal responsibility and introduced the category of diminished responsibility. Second, a controversial law for preventive detention (rétention de sûretê) was enacted in 2008, according to which criminals with severe personality disorders are subject to incarceration even after the completion of their prison sentences if they are still considered to pose a danger to the public. Third, the revision of mental health laws in 2011 altered the forms of involuntary psychiatric treatments, stipulating a judge's authority to decide treatment. In parallel with these legal reforms, the psychiatric treatment system for offenders with mental disorders has been reconstructed. The number of difficult patient units (unités pour malades difficiles) has increased from four to ten across the nation in order to meet the needs of patients transferred from general psychiatric institutions for the reason of being unmanageable. In the penitentiary system, new facilities have been established to cope with the growing number of inmates with mental disorders. As background to these changes, it is pointed out that the current psychiatric system has undergone deinstitutionalization and become less tolerant of aggressive behavior in patients. In the broader context, public sensitivity towards severe crime, as shown by the sensation triggered by serious crimes conducted by pedophiles, seems to urge tough policies. In the 2000 s, several homicides committed by psychiatric patients had a great impact on the public, which led President Sarkozy to issue a statement calling for stronger security in psychiatric institutions. The harsh attitude of courts towards psychiatric practices is illustrated by a 2012 ruling; after a patient escaped from the hospital and hacked an elderly man to death, his psychiatrist was sentenced to a one-year suspended prison sentence for failing to recognize the danger that the patient posed to the public. Another lawsuit was raised against a psychiatrist following this case. Apparently, a sense of crisis is growing among psychiatric professionals. Their concerns are based on several points. Introduction of diminished responsibility may narrow the possibility of acquittal by reason of insanity, and lead to the criminalization of those with mental disorders. Dangerousness (dangerosité), pivotal in the procedure of preventive detention, is not a medical concept, but is instead based on the erroneous identification of criminality and mental disorders. Therefore, it is unreasonable to entrust the evaluation of dangerousness to psychiatric expertise. Court intervention in the process of deciding appropriate treatment may intensify judicialization (judiciarisation) of psychiatry. Establishment of facilities for prisoners within the mental health system would create a new segregating function of psychiatry. Thus, French experience seems to be figuring out all the challenges that contemporary metal health is facing. Above all, effective measures should be taken to prevent patients from entering the criminal justice system. Following this recommendation would be helpful in Japan, where a new forensic mental health system has just started.


Subject(s)
Commitment of Mentally Ill/legislation & jurisprudence , Crime/legislation & jurisprudence , Forensic Psychiatry/legislation & jurisprudence , Mental Health/legislation & jurisprudence , Prisoners/psychology , France , Humans , Japan , Jurisprudence
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