Altered Cortico–Striatal Functional Connectivity During Resting State in Obsessive–Compulsive Disorder

Background: Neuroimaging studies show that obsessive–compulsive disorder (OCD) is characterized by an alteration of the cortico–striato–thalamo–cortical (CSTC) system in terms of an imbalance of activity between the direct and the indirect loop of the CSTC. As resting-state functional connectivity (FC) studies investigated only specific parts of the CSTC in patients with OCD up to now, the present study aimed at exploring FC in the CSTC as a whole. Methods: We investigated potential alterations in resting-state FC within the CSTC system in 44 OCD patients and 40 healthy controls by taking into consideration all relevant nodes of the direct and indirect CSTC loop. Results: Compared to healthy controls, OCD patients showed an increased FC between the left subthalamic nucleus (STN) and the left external globus pallidus (GPe), as well as an increased FC between the left GPe and the left internal globus pallidus (GPi). Conclusion: These findings may contribute to a better understanding of the OCD pathophysiology by providing further information on the connectivity alterations within specific regions of the CSTC system. In particular, increased FC between the STN and the left GPe may play a major role in OCD pathology. This assumption is consistent with the fact that these regions are also the main target sites of therapeutic deep brain stimulation in OCD

Increased Default Mode Network Connectivity in Obsessive-Compulsive Disorder During Reward Processing

Objective: Obsessive-compulsive disorder (OCD) is characterized by anxiety-provoking, obsessive thoughts (i.e., obsessions) which patients react to with compulsive behaviors (i.e., compulsions). Due to the transient feeling of relief following the reduction of obsession-induced anxiety, compulsions are often described as relieving or even rewarding. Several studies investigated functional activation during reward processing in OCD, but findings are heterogeneous up to now and little is known about potential alterations in functional connectivity. Method: Against this background we studied OCD patients (n=44) and healthy controls (n=37) during the receipt ofmonetary reward by assessing both activation and functional connectivity. Results: Patients showed a decreased activation in several frontal regions and the posterior cingulate (PCC, BA31) together with a stronger connectivity between the PCC and the vmPFC (BA10). Conclusion: Present findings demonstrate an increased connectivity in patients within major nodes of the default mode network (DMN)-a network known to be involved in the evaluation of internal mental states. These results may indicate an increased activity of internal, self-related processing at the expense of a normal responsiveness toward external rewards and incentives. This, in turn, may explain the constant urge for additional reinforcement and patients' inability to inhibit their compulsive behaviors

Association between hippocampus volume and symptom profiles in obsessive-compulsive disorder

Background: The hippocampus has recently been identified to play a key role in the pathophysiology of adult obsessive-compulsive disorder (OCD). Surprisingly, there is only limited evidence regarding the potential relationships with symptom dimensions. Due to the heterogeneity of symptoms in OCD, we aimed at further examining, whether hippocampal volume differences might be related to symptom profiles instead of single symptom dimensions. Methods: In order to find out more about the potential association between clinical symptom profiles and alterations in hippocampal volume we categorized a large sample of OCD patients (N = 66) into distinct symptom profile groups using K-means clustering. In addition, hippocampal volumes of the different symptom profile groups were compared with hippocampal volumes in a sample of 66 healthy controls. Results: We found significant differences in hippocampal volume between the different symptom profile groups which remained significant after correcting for age, sex, total intracranial volume, OCI-total score, depression, medication, disease duration and scanner. The patient group characterized by overall lower symptom scores and without high symptom severity in any specific domain showed the highest hippocampal volume. Finally, the comparison with healthy controls demonstrated significantly lower hippocampal volumes in those patients whose symptom profile was characterized by a high severity of ordering and checking symptoms. Conclusions: Present results provide further confirmation for alterations in hippocampus structure in OCD and suggest that symptom profiles which take into account the multi-symptomatic character of the disorder should be given greater attention in this context

Altered Cortico–Striatal Functional Connectivity During Resting State in Obsessive–Compulsive Disorder

Background: Neuroimaging studies show that obsessive–compulsive disorder (OCD) is characterized by an alteration of the cortico–striato–thalamo–cortical (CSTC) system in terms of an imbalance of activity between the direct and the indirect loop of the CSTC. As resting-state functional connectivity (FC) studies investigated only specific parts of the CSTC in patients with OCD up to now, the present study aimed at exploring FC in the CSTC as a whole.Methods: We investigated potential alterations in resting-state FC within the CSTC system in 44 OCD patients and 40 healthy controls by taking into consideration all relevant nodes of the direct and indirect CSTC loop.Results: Compared to healthy controls, OCD patients showed an increased FC between the left subthalamic nucleus (STN) and the left external globus pallidus (GPe), as well as an increased FC between the left GPe and the left internal globus pallidus (GPi).Conclusion: These findings may contribute to a better understanding of the OCD pathophysiology by providing further information on the connectivity alterations within specific regions of the CSTC system. In particular, increased FC between the STN and the left GPe may play a major role in OCD pathology. This assumption is consistent with the fact that these regions are also the main target sites of therapeutic deep brain stimulation in OCD

Atypical Self-Focus Effect on Interoceptive Accuracy in Anorexia Nervosa

Background: Interoceptive abilities are known to be affected in anorexia nervosa (AN). Previous studies could show that private self-focus can enhance interoceptive accuracy (IAcc) in healthy participants. As body dissatisfaction is high in AN, confrontation with bodily features such as the own face might have a directly opposed effect in AN. Whether patients with AN can benefit from self-focus in their IAcc and whether this pattern changes over the time-course of cognitive behavioral therapy was investigated in this study. Methods: 15 patients with AN from the Psychosomatic Clinic in Windach were assessed three times in the time course of a standardized cognitive-behavioral therapy. They were compared to 15 controls, recruited from Ulm University and tested in a comparable setting. Both groups performed the heartbeat perception task assessing interoceptive accuracy (IAcc) under two conditions either enhancing (Self) or decreasing (Other) self-focused attention. Furthermore, body dissatisfaction was assessed by a subscale of the Eating Disorder Inventory 2. Results: Patients with AN scored higher in IAcc when watching others’ faces as compared to one’s own face while performing the heartbeat perception task. The opposite pattern was observed in controls. IAcc remained reduced in AN as compared to controls in the time-course of cognitive-behavioral therapy, while body-dissatisfaction improved in AN. High body dissatisfaction was related to poorer IAcc in the Self condition. Conclusions: Our findings suggest that using self-focused attention reduces IAcc in AN while the opposite pattern was observed in controls. Confronting anorexic patients with bodily features might increase body-related avoidance and therefore decrease interoceptive accuracy. The current study introduces a new perspective concerning the role of interoceptive processes in AN and generates further questions regarding the therapeutic utility of methods targeting self-focus in the treatment of AN

The Effects of a Standardized Cognitive-Behavioural Therapy and an Additional Mindfulness-Based Training on Interoceptive Abilities in a Depressed Cohort

Background: Interoceptive accuracy and sensibility are decreased in depressive samples. However, different studies showed that cognitive-behavioural therapy (CBT) and mindfulness interventions are promising approaches to improve interoceptive abilities. Based on these findings, the study aims to investigate the pre–post effect of CBT in a depressive sample. Additionally, we examined the effect of mindfulness-based stress reduction (MBSR) training in the context of CBT. Methods: Sixty depressive patients were investigated over four weeks, with two conditions—CBT vs. CBT + MBSR. Further, the changes in interoceptive abilities (interoceptive accuracy and sensibility) of the depressive patients were compared to baseline data of healthy controls. Results: The depressive patients showed significantly higher levels of depression and lower mindfulness and interoceptive abilities than healthy controls. The depressive sample showed a significant decrease in depressive symptoms and increased mindfulness and interoceptive abilities after CBT. Lastly, depressive patients of the CBT + MBSR condition did not differ from those who only received CBT in the levels of depression, mindfulness or interoceptive abilities over the time course. Discussion: This study demonstrates a positive effect of CBT on interoceptive abilities in a depressive sample. It is shown that the depressive sample did not profit from additional mindfulness training. It can be concluded that CBT is an efficient treatment, resulting in increased interoceptive abilities. Unexpectedly, the combination of CBT and MBSR has no additional effect on these changes. Future studies should investigate the effect of MBSR as a stand-alone therapy

Interoceptive deficits in patients with obsessive-compulsive disorder in the time course of cognitive-behavioral therapy.

Interoception is impaired in different psychiatric disorders and is also associated with emotions. Only one study could show a higher interoceptive accuracy (IAcc) in patients with obsessive-compulsive disorder (OCD). Based on the predictive coding system we assume contrary results, indicating a decreased IAcc in patients with OCD. So far, there is no study investigating the effect of cognitive-behavioral therapy on IAcc in patients with OCD. Therefore, we hypothesize that patients with OCD improve their IAcc during the time course of therapy compared to healthy controls. Twenty-six patients with OCD from the Psychosomatic Clinic in Windach were examined in the time course of cognitive-behavioral therapy. They were compared to 26 matched healthy controls. IAcc via the heartbeat perception task as well as questionnaire data (OCD-, depression- and anxiety symptoms) were assessed. Results showed that IAcc, OCD-, depression- and anxiety symptoms were attenuated in patients with OCD. Patients recovered in the time course of therapy regarding OCD-, depression- and anxiety symptoms. Interoceptive deficits did not change in the time course of cognitive-behavioral therapy. We demonstrated that IAcc is affected in patients with OCD and this deficit does not change during the time course of a standardized therapy. Future studies should investigate, whether an inaccuracy in perceiving one's bodily signals constitutes a risk factor for relapse. Further, it could be examined if IAcc can be increased via self- and body focus interventions in patients with OCD

Interoceptive processes in anorexia nervosa in the time course of cognitive-behavioral therapy: a pilot study

Objective Previous studies report reduced interoceptive abilities in anorexia nervosa (AN) using various methods. Recent research suggests that different levels of interoceptive processes aiming at different subdomains of interoceptive abilities must be further distinguished as these levels can be differentially affected. Two important levels refer to interoceptive accuracy (IA) derived from objective performance tasks such as the heartbeat detection task and interoceptive sensibility (IS) as assessed by self-report. There is a lack of studies investigating both IA and IS in AN and examining them in the time course of therapy. The aim of this pilot study was to evaluate the different interoceptive processes – especially IA and IS – in the time course of therapy. Methods Fifteen patients with AN (restricting type) from the Psychosomatic Clinic in Windach were investigated three times (T1, T2, T3) during a standardized cognitive-behavioral therapy and compared with 15 matched healthy controls assessed at Ulm University in a comparable design. All participants performed the heartbeat detection task examining IA and completed standard psychological assessments including an assessment of IS. Results Patients with AN showed a significantly decreased weight, higher levels of depression, and both reduced IA and IS compared to healthy controls at T1. Following therapy, patients recovered in terms of weight and depression symptomatology. A descriptive trend for recovering from IA and IS was observed. Discussion Our findings suggest that interoceptive deficits are present in recovered patients. Therefore, further investigations are needed with more patients, differentiating between relapsed and recovered patients, and more specific training methods to improve interoceptive processes

The effects of a standardized cognitive-behavioural therapy and an additional mindfulness-based training on interoceptive abilities in a depressed cohort

Background: Interoceptive accuracy and sensibility are decreased in depressive samples. However, different studies showed that cognitive-behavioural therapy (CBT) and mindfulness interventions are promising approaches to improve interoceptive abilities. Based on these findings, the study aims to investigate the pre–post effect of CBT in a depressive sample. Additionally, we examined the effect of mindfulness-based stress reduction (MBSR) training in the context of CBT. Methods: Sixty depressive patients were investigated over four weeks, with two conditions—CBT vs. CBT + MBSR. Further, the changes in interoceptive abilities (interoceptive accuracy and sensibility) of the depressive patients were compared to baseline data of healthy controls. Results: The depressive patients showed significantly higher levels of depression and lower mindfulness and interoceptive abilities than healthy controls. The depressive sample showed a significant decrease in depressive symptoms and increased mindfulness and interoceptive abilities after CBT. Lastly, depressive patients of the CBT + MBSR condition did not differ from those who only received CBT in the levels of depression, mindfulness or interoceptive abilities over the time course. Discussion: This study demonstrates a positive effect of CBT on interoceptive abilities in a depressive sample. It is shown that the depressive sample did not profit from additional mindfulness training. It can be concluded that CBT is an efficient treatment, resulting in increased interoceptive abilities. Unexpectedly, the combination of CBT and MBSR has no additional effect on these changes. Future studies should investigate the effect of MBSR as a stand-alone therapy

Interoceptive processes in anorexia nervosa in the time course of cognitive-behavioral therapy: A pilot study

Objective: Previous studies report reduced interoceptive abilities in anorexia nervosa (AN) using various methods. Recent research suggests that different levels of interoceptive processes aiming at different subdomains of interoceptive abilities must be further distinguished as these levels can be differentially affected. Two important levels refer to interoceptive accuracy (IA) derived from objective performance tasks such as the heartbeat detection task, and interoceptive sensibility (IS) as assessed by self-report. There is a lack of studies investigating both IA and IS in AN, and examining them in the time course of therapy. Aim of the pilot study was to evaluate the different interoceptive processes – especially IA and IS – in the time course of therapy.Methods: Fifteen patients with AN (restricting type) from the Psychosomatic Clinic in Windach were investigated three times (T1, T2, T3) during a standardized cognitive-behavioral therapy and compared to fifteen matched healthy controls assessed at Ulm University in a comparable design. All participants performed the heartbeat detection task examining IA and completed standard psychological assessments including an assessment of IS. Results: Patients with AN showed a significantly decreased weight, higher levels of depression and both reduced IA and IS compared to healthy controls at T1. Following therapy, patients recovered in terms of weight and depression symptomatology. A descriptive trend for recovering from IA and IS was observed. Discussion: Our findings suggest that interoceptive deficits are present in recovered patients. Therefore, further investigations are needed with more patients, differentiating between relapsed and recovered patients, and more specific training methods to improve interoceptive processes