Autonomic responses and neural-cardiac coupling during individually tailored symptom provocation in obsessive-compulsive disorder

Heart rate and heart rate variability in obsessive-compulsive disorder: Evidence from patients and unaffected first-degree relatives

Altered heart rate (HR) and heart rate variability (HRV) are common observations in psychiatric disorders. Yet, few studies have examined these cardiac measures in obsessive-compulsive disorder (OCD). The current study aimed to investigate HR and HRV, indexed by the root mean square of successive differences (RMSSD) and further time domain indices, as putative biological characteristics of OCD. Electrocardiogram was recorded during a five-minute resting state. Group differences between patients with OCD (n = 96), healthy participants (n = 112), and unaffected first-degree relatives of patients with OCD (n = 47) were analyzed. As potential moderators of group differences, we examined the influence of age and medication, respectively. As results indicated, patients with OCD showed higher HR and lower HRV compared to healthy participants. These group differences were not moderated by age. Importantly, subgroup analyses showed that only medicated patients displayed lower HRV compared to healthy individuals, while HR alterations were evident in unmedicated patients. Regarding unaffected first-degree relatives, group differences in HRV remained at trend level. Further, an age-moderated group differentiation showed that higher HRV distinguished relatives from healthy individuals in young adulthood, whereas at higher age lower HRV was indicative of relatives. Both the role of familial risk and medication in HRV alterations need further elucidation. Pending future studies, alterations in HR and potentially HRV might serve as useful indices to characterize the pathophysiology of OCD.

Comorbid anxiety is associated with more changes in the Management of Postural Orthostatic Tachycardia Syndrome

OBJECTIVE

Postural Orthostatic Tachycardia Syndrome (POTS) is not an anxiety disorder, but it shares similar symptomatology. The impact of this comorbidity on management is unknown. This information may lead to better strategies to improve the care of this subgroup.

METHOD

The electronic medical records of 322 patients seen at our institution between 2018 and 2022 with confirmed POTS diagnoses were analyzed. Demographics, anxiety comorbidities, questionnaire responses, and treatment course changes were collected. Negative binomial regression models examined if the presence of an anxiety disorder was associated with the number of POTS treatment course changes offset by observation time.

RESULTS

When adjusted for sex, age, baseline GAD-7 score, and baseline PROMIS global mental health score, those with a diagnosis of an anxiety disorder had2.6 times the incident rate of treatment changes for POTS management (IRR = 2.66 (95% CI: 1.43-4.95)).

CONCLUSION

Individuals carrying the diagnosis of an anxiety disorder had an increase in the incident rate of treatment changes for POTS therapy. This finding may be due to the underlying pathophysiology and treatment of anxiety disorders, the effect of bias, and difficulty with symptom differentiation. More work needs to be done to determine how to best care for POTS patients with comorbid anxiety.

A Systematic Review of Clinical Psychophysiology of Obsessive-Compulsive Disorders: Does the Obsession with Diet Also Alter the Autonomic Imbalance of Orthorexic Patients?

(1) Background: A new mental illness is attracting the attention of researchers and mental health professionals. Orthorexia nervosa (ON) is a possible new mental disorder, the main symptom of which is an obsessive and insecure focus on healthy foods and consequent compulsive behaviors. There is a common consensus among researchers that ON is considered partly overlapping with obsessive-compulsive disorders (OCDs). (2) Methods: MEDLINE and Scopus were searched for articles published in the last 10 years regarding the psychophysiological aspects of OCD and ON. Eight studies met the eligibility criteria. The inclusion criteria encompassed adults diagnosed with OCD and/or ON. However, only studies involving OCD patients were found. (3) Results: Some research groups have shown that OCD disorders can be considered among anxiety disorders because they are characterized by anxious hyper activation. Other research, however, has shown profiles characterized by low psychophysiological reactivity to stressful stimuli. Despite this, there seems to be a consensus on the poor inhibition abilities, even when activation is low, and the dissociation between cognitive and psychophysiological activation emerged. (4) Conclusions: However discordant, some points seem to bring the researchers to agreement. In fact, there is consensus on conducting a multidimensional assessment that can measure all of the aspects of suffering (cognition, emotion, and behavior) and highlight the poor body-mind integration. This clinical approach would make it possible to propose interventions aimed at treating some mental illnesses such as food obsession that can paradoxically impair the psychophysical balance. Nevertheless, the applied systematizing approach to existing studies on ON is very much needed for better understanding of the psychophysical nature of this new mental illness and its implications for prevention and treatment.

Neural correlates of emotional reactivity predict response to cognitive-behavioral therapy in obsessive-compulsive disorder

BACKGROUND

Examining predictive biomarkers to identify individuals who will likely benefit from a specific treatment is important for the development of targeted interventions. The late positive potential (LPP) is a neural marker of attention and elaborated stimulus processing, and increased LPP responses to negative stimuli are characteristic of pathological anxiety. The present study investigated whether LPP reactivity would prospectively predict response to cognitive-behavioral therapy (CBT), the first-line treatment for obsessive-compulsive disorder (OCD).

METHODS

To this end, the LPP in response to negative as compared to neutral pictures was examined in 45 patients with OCD, who underwent CBT in a naturalistic outpatient setting. LPP amplitudes were used as predictors of symptom reduction after CBT.

RESULTS

We found that higher LPP amplitudes to negative relative to neutral stimuli were predictive of lower self-reported OCD symptoms after completion of CBT, controlling for pre-treatment symptoms. Further, LPP reactivity was negatively correlated with self-reported habitual use of suppression in everyday life.

LIMITATIONS

Some participants had already begun treatment at the time of study participation. Overall, results need further replication in larger samples and standardized therapy settings.

CONCLUSIONS

The current findings suggest that patients with increased emotional reactivity benefit more from CBT, possibly through less avoidance of anxiety-provoking stimuli during exposure with response prevention, a crucial component in CBT for OCD. Although its clinical utility still needs to be evaluated further, the LPP constitutes a promising candidate as a prognostic marker for CBT response in OCD.

Heart rate variability in obsessive compulsive disorder in comparison to healthy controls and as predictor of treatment response

OBJECTIVE

Obsessive compulsive disorder (OCD) has a large impact on the quality of life of patients. It often takes years to get the right diagnosis and to receive treatment. Therefore, biomarkers that could inform the diagnostic process and provide information on response or non-response for first line treatment approaches are urgently needed. The aim of this study was to analyze whether (1) heart rate (HR) and heart rate variability (HRV) markers of the autonomous nervous system could distinguish between healthy controls (HC) and patients suffering from OCD and (2) HRV parameters additionally yield useful information to separate therapy-responders from non-responders.

METHODS

A fifteen-minute resting state ECG (electrocardiogram) was recorded from 51 unmedicated OCD patients before treatment and 28 HC. The function of the autonomic nervous system was assessed by using parameters of the HRV. Clinical Global Impression (CGI) scores served as baseline and outcome parameters following three to six months of therapy (cognitive behavioral therapy n = 18, selective-serotonin-reuptake-inhibitor n = 11 or combination n = 22). Differences between patients and HC and responders and non-responders were identified using analysis of covariance (ANCOVAs). Predictive values were calculated following binary regression modelling and receiver operating characteristics (ROC).

RESULTS

OCD patients revealed a significantly higher HR in comparison to HC. Although patients were thus characterized by increased sympathetic and decreased parasympathetic tone, treatment responders exhibited a larger High Frequency Power as a marker for increased parasympathetic activity at baseline. ROC-curves for OCD vs HC and R vs NR showed clinically relevant areas under curve (83%, 88% respectively).

CONCLUSIONS

These results are in line with findings of increased sympathetic and decreased parasympathetic activity in OCD in comparison to healthy subjects. The findings further provide clinically useful information on treatment response in OCD.

SIGNIFICANCE

Results may facilitate the clinical use of electrophysiological markers in OCD.

A Systematic Literature Review and Meta-analysis on Effectiveness of Neurofeedback for Obsessive-Compulsive Disorder

To evaluate the evidences related to the effectiveness of neurofeedback treatment for people with OCD. A literature review and meta-analysis of current controlled trials for patients with OCD symptoms was conducted across different databases. So, the primary outcome measure was OCD symptoms in subjects based on DSM IV. Y-BOCS was considered as primary outcomes. Nine met inclusion criteria (including 1211 patients). Analysis showed there was an important benefit of neurofeedback treatment in comparison to other treatments (MD = -6.815; 95% CI = [-9.033, -4.598]; P < 0.001). The results provide preliminary evidence that NFB is efficacious method for OCD and suggest that more clinical trials are needed to compare common treatment such as medication, neurological, and behavioral interventions.

Cardiovascular Autonomic Function Tests in Patients of Obsessive-Compulsive Disorder: A Cross-Sectional Study

BACKGROUND

Patients with psychiatric disorders are at an increased risk of developing cardiovascular disease, reducing life expectancy. Autonomic dysfunction has been linked to this increased risk; many studies have found reductions in heart rate variability (HRV). Only a few studies have systematically explored the relationship between obsessive-compulsive disorder (OCD) and autonomic function, and they have found contradicting results. The present study is intended to explore comprehensive autonomic functions in OCD patients and compare them with healthy controls.

METHODS

A total of 18 OCD patients meeting Diagnostic and Statistical Manual of Mental Disorders - 5 (DSM-5) criteria were enrolled to undergo comprehensive autonomic function testing, and the results were compared with 25 age- and sex-matched healthy controls.

RESULTS

Time-domain parameters of HRV such as standard deviation of the RR intervals, coefficient of variance of RR intervals, standard deviation of differences between adjacent RR intervals, root square of the mean of the sum of the squares of differences between adjacent RR intervals, and percentage of number of RR interval differences ≥ 50 ms were significantly lower in OCD patients, indicating lesser parasympathetic tone. Frequency-domain parameters such as total power and very low frequency were significantly lower in OCD patients, indicating a significant decrease in autonomic tone. Nonlinear parameters such as dispersion of points perpendicular to the line of identity and dispersion of points along the line of identity were significantly lower in OCD patients, indicating altered vagal and sympathetic tone. In autonomic reactivity tests, the fall in systolic blood pressure during the lying to standing test and change in diastolic blood pressure during the cold pressor test were significantly altered in OCD patients, indicating abnormal sympathetic reactivity. There was no significant correlation between autonomic parameters and the severity of OCD.

CONCLUSION

OCD is characterized by a decreased parasympathetic tone and abnormal sympathetic reactivity compared to normal controls.

fNIRS Evaluation of Frontal and Temporal Cortex Activation by Verbal Fluency Task and High-Level Cognition Task for Detecting Anxiety and Depression

Anxiety and depression are widespread psychosis which are believed to affect cerebral metabolism, especially in frontal and temporal cortex. The comorbidity patients of anxiety and depression (A&D) have more serious clinical symptoms. Functional near-infrared spectroscopy (fNIRS) is a noninvasive modality used to monitor human brain oxygenation, and it could be considered as a potential tool to detect psychosis which may lead to abnormal cerebral oxygen status when the brain is activated. However, how sensitive the cerebral oxygenation response to the cortex activation and whether these responses are consistent at different stages of A&D or different regions still remains unclear. In this study, a conventional physiological paradigm for cortex activation, i.e., verbal fluency task (VFT), and a relatively new paradigm, i.e., high-level cognition task (HCT), were compared to detect A&D through a longitudinal measurement of cerebral oxygen status by fNIRS. The A&D patients at the acute, consolidation and maintenance stages as well as the healthy subjects participated in the VFT and HCT paradigms, respectively. For the VTF paradigm, the subject was instructed to answer questions of phrase constructions within 60 s. For the HCT paradigm, the subject was instructed to categorize items, logical reasoning, and comprehensive judgment and write down the answers within 60 s. For most of the subjects, the oxy-Hb is found to increase remarkably, accompanied with a relatively small reduction in deoxy-Hb when subject to both paradigms. The statistical analyses show a relatively large variability within any group, leading to the significant difference that was only found between A&D at the acute stage and healthy subjects in the temporal lobe region (p < 0.001). Nevertheless, HCT would activate more oxygen increment when compared with the VFT, with a large integral value in oxy-Hb. On average, the oxy-Hb integral value of the A&D patients differs substantially at different stages when subject to HCT paradigm. Moreover, the prefrontal lobe and temporal lobe responses were more consistent to the HCT paradigm rather than the VFT paradigm. Under the VFT paradigm, however, no remarkable difference in integral value was found among the three stages, either at the prefrontal lobe or at the temporal lobe. This study indicated that HCT, which is intensively involved in brain function, would activate more oxygenation changes in the cerebral cortex. Additionally, with good performance at distinguishing different stages according to the oxy-Hb criterion, the HCT has the potential to evaluate the therapeutic effects for A&D patients.

Association between Obsessive-Compulsive Symptoms and Long-Term Cardiac Outcomes in Patients with Acute Coronary Syndrome: Effects of Depression Comorbidity and Treatment

OBJECTIVE

The role of obsessive-compulsive symptoms (OCS) in patients with acute coronary syndrome (ACS) is not well elucidated. This study investigated the association between OCS and the long-term prognosis of ACS in tandem with depression comorbidity and treatment.

METHODS

A cross-sectional baseline study and a nested 24-week double-blind escitalopram-placebo controlled trial were carried out between May 2007 and March 2013, and then a 5-12-year follow-up for major adverse cardiac events (MACE) was conducted. A total of 1,152 patients with ACS were stratified by baseline depression comorbidity and treatment allocation into four groups: no depression (706 patients), depression and taking escitalopram (149 patients), depression and taking a placebo (151 patients), and depression and receiving medical care as usual (CAU; 146 patients). OCS were evaluated using the Symptom Checklist-90-Revised Obsessive-Compulsive symptom domain. During the follow-up, Kaplan-Meier event rates for MACE outcomes were calculated, and hazard ratios were estimated using Cox regression models after adjusting for a range of covariates.

RESULTS

A higher OCS score at baseline was associated with a worse ACS prognosis after adjusting for relevant covariates and across MACE outcomes. This association varied according to the depression comorbidity. The association was significant in patients without depression and depressive patients receiving placebos and CAU, but not in depressive patients on escitalopram.

CONCLUSION

Evaluating OCS and depression is recommended during the early phase of ACS. Treatment for OCS may improve the longterm cardiac outcomes of patients with ACS.

Neural correlates of symptom provocation in pediatric obsessive-compulsive disorder

•

Largest controlled pediatric OCD symptom provocation study.

•

Novel standardized symptom provocation picture set for pediatric OCD.

•

Behavioral group differences strongest for ‘Just Right’ factor.

•

Temporal pole recruited by OCD group.

Obsessive-compulsive disorder

(OCD)-affected adults and children exhibit three to four symptom dimensions with distinct but overlapping neural correlates. No symptom provocation behavioural or imaging study has examined all symptom dimensions in a pediatric OCD sample.

Method

Clinically diagnosed pediatric OCD-affected participants (n = 25) as well as age, gender and Tanner pubertal stage-matched healthy controls (HCs; n = 24) (total sample: mean age = 14.77 ± 2.93 years; age range = 9–18 years; 35% male) viewed alternating blocks of OCD symptom provocation (Contamination, Bad Thoughts, and Just Right symptom dimensions), Fear, Neutral and Rest (i.e. fixation) conditions during functional magnetic resonance imaging. A region-of-interest analysis used seeds based upon results of an adult OCD meta-analysis

Results

OCD participants found OCD symptom-related stimuli bothersome, particularly when compared to controls in the “Just Right” symptom dimension. Pediatric OCD patients exhibited greater recruitment of the left superior temporal gyrus (STG) than healthy controls during combined symptom provocation versus neutral conditions.

Conclusion

Findings suggest involvement of the temporal poles rather than in classic cortico-striatal-thalamico-cortical circuits in pediatric OCD during symptom provocation.

The Role of Perceived Control in the Psychophysiological Responses to Disgust of Subclinical OCD Women

Obsessive‒compulsive disorder (OCD), and especially contamination obsessions and washing compulsions, has been related to disgust. However, when its cardiovascular correlates have been studied, contradictory results have been found, including heart rate accelerations and decelerations. The aim of this study is to analyze emotional, cognitive, and cardiovascular responses in nonclinical (control) and subclinical participants with obsessive‒compulsive contamination/washing symptoms when confronted with a disgusting stimulus. Twenty-seven participants (14 subclinical OCD) completed a behavioral avoidance task with a contamination-based stimulus while their heart rate and subjective variables were measured. Results showed heart rate reductions in both samples, whereas subjective measures reflected higher disgust, anxiety, dirtiness, and emotional valence in the subclinical sample. However, at the same time, the sense of dominance was lower in the control group. In conclusion, our results support a heart rate deceleration during exposure to a disgusting stimulus dissociated from the subjective experience.

The efficacy of biofeedback approaches for obsessive-compulsive and related disorders: A systematic review and meta-analysis

Biofeedback is applied to target excessive and/or deficient physiological signals to help patients identifying and self-managing their symptoms. Biofeedback has been employed in psychiatric disorders, including obsessive-compulsive disorder (OCD), mainly by using neural signals - neurofeedback. Recently, OCD has been integrated into the obsessive-compulsive and related disorders (OCD&RD) category (body dysmorphic, hoarding, trichotillomania/hair-pulling, and excoriation/skin-picking disorders). The efficacy of biofeedback for OCD&RD is still unknown. Our work provides a complete overview of publications assessing the therapeutic efficacy of biofeedback in OCD&RD with a systematic review and meta-analysis. We found ten studies involving 102 OCD participants (three randomized controlled trials) mostly applying neurofeedback (one publication used thermal biofeedback). Five neurofeedback studies were selected for meta-analysis (89 patients; two randomized controlled trials). The overall effect size within the treatment group varied between medium to large, but high heterogeneity and inconsistency values were found. The methodological quality was low indicating a high risk of bias. In conclusion, a beneficial effect of neurofeedback for OCD patients was found but also critical limitations on methodology, high heterogeneity among studies, and a putative reporting bias. Future research following high-quality guidelines should be conducted to address the efficacy of biofeedback approaches for OCD&RD.

Emotional Processing in Obsessive-Compulsive Disorder: A Systematic Review and Meta-analysis of 25 Functional Neuroimaging Studies

BACKGROUND

Patients with obsessive-compulsive disorder (OCD) experience aversive emotions in response to obsessions, motivating avoidance and compulsive behaviors. However, there is considerable ambiguity regarding the brain circuitry involved in emotional processing in OCD, especially whether activation is altered in the amygdala.

METHODS

We conducted a systematic literature review and performed a meta-analysis-seed-based d mapping-of 25 whole-brain neuroimaging studies (including 571 patients and 564 healthy control subjects) using functional magnetic resonance imaging or positron emission tomography, comparing brain activation of patients with OCD and healthy control subjects during presentation of emotionally valenced versus neutral stimuli. Meta-regressions were employed to investigate possible moderators.

RESULTS

Patients with OCD, compared with healthy control subjects, showed increased activation in the bilateral amygdala, right putamen, orbitofrontal cortex extending into the anterior cingulate and ventromedial prefrontal cortex, and middle temporal and left inferior occipital cortices during emotional processing. Right amygdala hyperactivation was most pronounced in unmedicated patients. Symptom severity was related to increased activation in the orbitofrontal and anterior cingulate cortices and precuneus. Greater comorbidity with mood and anxiety disorders was associated with higher activation in the right amygdala, putamen, and insula as well as with lower activation in the left amygdala and right ventromedial prefrontal cortex.

CONCLUSIONS

Patients with OCD show increased emotional processing-related activation in limbic, frontal, and temporal regions. Previous mixed evidence regarding the role of the amygdala in OCD has likely been influenced by patient characteristics (such as medication status) and low statistical power.

Meta-analytic review of the effects of a single dose of intranasal oxytocin on threat processing in humans

BACKGROUND

Heightened threat sensitivity is a transdiagnostic feature in several psychiatric disorders. The neuropeptide oxytocin has been shown to reduce fear related behaviours and facilitated fear extinction in animals. These findings have led to increasing interest to explore the effects of intranasal oxytocin on threat processing in humans.

METHODS

The review included 26 studies (N = 1173), nine of which included clinical populations (N = 234). The clinical groups included were people with borderline personality disorder (BPD), anorexia nervosa, bulimia nervosa, depression, anxiety, and alcohol dependence disorder. We examined the effects of a single dose of intranasal oxytocin on startle response, attentional responses, and behavioural responses to threat.

RESULTS

A single dose of intranasal oxytocin significantly increased the physiological startle response to threat in healthy people with a small effect size. However, oxytocin did not have significant effects on attentional bias towards social or disorder-specific threat, fixation towards threatening stimuli among healthy or clinical populations, or on threat related behavioural approach or avoidance responses.

LIMITATIONS

No studies investigated the effects of oxytocin on the startle response to threat among clinical populations. Additionally, only one of the reviewed studies had sufficient power to detect at least a moderate effect of oxytocin according to our criterion.

DISCUSSION

The synthesis of literature suggest that oxytocin may influence the salience of threatening stimuli among healthy individuals, increasing the startle response to threat. It would be of interest to investigate the effects of oxytocin on the startle response to threat among clinical populations.

Modulation of error monitoring in obsessive-compulsive disorder by individually tailored symptom provocation

BACKGROUND

The enhanced error monitoring in patients with obsessive-compulsive disorder (OCD), typically measured with the error-related negativity (ERN), has been found to be temporally stable and independent of symptom expression. Here, we examined whether the error monitoring in patients with OCD could be experimentally modulated by individually tailored symptom provocation.

METHOD

Twenty patients with OCD and 20 healthy controls performed a flanker task in which OCD-relevant or neutral pictures were presented prior to a flanker stimulus. An individualized stimulus set consisting of the most provoking images in terms of OCD symptoms was selected for each patient with OCD. Response-locked event-related potentials were recorded and used to examine the error-related brain activity.

RESULTS

Patients with OCD showed larger ERN amplitudes than did control subjects in both the OCD-symptom provocation and neutral conditions. Additionally, while patients with OCD exhibited a significant increase in the ERN under the OCD-symptom provocation condition when compared with the neutral condition, control subjects showed no variation in the ERN between the conditions.

CONCLUSIONS

Our results strengthen earlier findings of hyperactive error monitoring in OCD, as indexed by higher ERN amplitudes in patients with OCD than in controls. Importantly, we showed that the patients' overactive error-signals were experimentally enhanced by individually tailored OCD-symptom triggers, thus suggesting convincing evidence between OCD-symptoms and ERN. Such findings imply that therapeutic interventions should target affective regulation in order to alleviate the perceived threatening value of OCD triggers.

Different functioning of prefrontal cortex predicts treatment response after a selective serotonin reuptake inhibitor treatment in patients with major depression

BACKGROUND

Major depressive disorder (MDD) is often resistant to treatment with usual approaches. Patients with MDD have shown hypofunction of the frontotemporal cortex in verbal fluency test (VFT)-related near-infrared spectroscopy (NIRS).

METHODS

We examined whether the reactions to drug treatment in treatment-naive patients with MDD could be predicted by NIRS outcomes at the initial investigation. All subjects underwent psychological testing to determine levels of anxiety and depression. VFT was used to examine the functioning of the frontotemporal lobes. We administered selective serotonin reuptake inhibitors (SSRIs) for 12 weeks. Subjects included 28 patients with MDD with response to SSRIs (Response group), 19 with no response (Non-Response group), and 63 age-, sex-, and education years-matched healthy controls (HC).

RESULTS

We found in the frontotemporal region that hemodynamic responses were significantly smaller in patients with Response and Non-Response groups than in HC before treatment. We also found in the medial frontal region that hemodynamic responses were significantly larger in patients with Response groups than in patients with Non-Response group before treatment. Patients with MDD scored significantly higher anxiety and depressive states than those in HC on several measures. The Response and Non-Response groups also had higher scores in future denial, threat prediction, self-denial, past denial, and interpersonal threat sections of Anxiety Cognition Scale (DACS). According to the stepwise regression analysis, one variable was determined as independent predictors of response: confusion (Post-POMS).

LIMITATIONS

The number of patients and healthy controls was relatively small, and we will increase the number of participants in future studies. NIRS has reduced spatial resolution, which confuses the identification of the measurement position when using NIRS alone.

CONCLUSION

Cognitive vulnerabilities are associated with predictors of SSRI treatment response. Different hemodynamic activities in the frontotemporal cortex predict response to SSRI treatment in MDD.

Changes in disgust and heart rate during exposure for Obsessive Compulsive Disorder: A case series

BACKGROUND AND OBJECTIVES

The emotion of disgust has been suggested as a factor contributing to a poor response to Cognitive Behaviour Therapy (CBT) in the treatment of Obsessive Compulsive Disorder (OCD). However, only limited information is available about the phenomenology of disgust in clinical OCD and the physiological mechanisms involved. This case series was designed to explore the phenomenology of OCD and the physiological activity associated with the emotion of disgust.

METHODS

State disgust and heart rate was measured in eleven participants attending treatment for OCD during exposure relevant to their individual formulation.

RESULTS

All participants with contamination and most patients with blood and injury related fears experienced a prominent increase in state disgust during exposure. These participants also had absent heart rate acceleration during exposure. Disgust response correlated with heart rate response (r = -0.63, p < 0.01) and Root Mean Square of Successive Differences (RMSSD) (r = 0.52, p < 0.01).

LIMITATIONS

The design using ecologically valid stimuli and the limited number of participants did not allow between subject comparisons or more detailed analysis of relationship between trait and state disgust and between disgust and severity of OCD.

CONCLUSIONS

Our findings show that a large proportion of our case series with OCD experience prominent disgust with signs of increased vagal tonus during their exposure. Such experiences differ from the concept of adrenergic activation used for psychoeducation in CBT and appraisals of harm and this may result in poorer therapeutic outcome.

Disruption of effective connectivity from the dorsolateral prefrontal cortex to the orbitofrontal cortex by negative emotional distraction in obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) has been associated with abnormal cognitive and emotional functions and these dysfunctions may be dependent on the disruption of dynamic interactions within neuronal circuits associated with emotion regulation. Although several studies have shown the aberrant cognitive-affective processing in OCD patients, little is known about how to characterize effective connectivity of the disrupted neural interactions. In the present study, we applied effective connectivity analysis using dynamic causal modeling to explore the disturbed neural interactions in OCD patients.

METHOD

A total of 20 patients and 21 matched healthy controls performed a delayed-response working memory task under emotional or non-emotional distraction while undergoing functional magnetic resonance imaging.

RESULTS

During the delay interval under negative emotional distraction, both groups showed similar patterns of activations in the amygdala. However, under negative emotional distraction, the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) exhibited significant differences between groups. Bayesian model averaging indicated that the connection from the DLPFC to the OFC was negatively modulated by negative emotional distraction in patients, when compared with healthy controls (p < 0.05, Bonferroni-corrected).

CONCLUSIONS

Exaggerated recruitment of the DLPFC may induce the reduction of top-down prefrontal control input over the OFC, leading to abnormal cortico-cortical interaction. This disrupted cortico-cortical interaction under negative emotional distraction may be responsible for dysfunctions of cognitive and emotional processing in OCD patients and may be a component of the pathophysiology associated with OCD.

Positive and negative emotional contexts unevenly predict episodic memory

The aim of this study was to investigate whether the recognition of faces with neutral expressions differs when they are encoded under different emotional contexts (positive, negative or non-emotional). The effects of the emotional valence context on the subsequent memory effect (SME) and the autonomic responses were also examined. Twenty-eight participants performed a betting-game task in which the faces of their virtual opponents were presented in each trial. The probability of winning or losing was manipulated to generate positive or negative contexts, respectively. Additionally, the participants performed the same task without betting as a non-emotional condition. After the encoding phase, an old/new paradigm was performed for the faces of the virtual opponents. The recognition was superior for the faces encoded in the positive contexts than for the faces encoded in the non-emotional contexts. The skin conductance response amplitude was equivalent for both of the emotional contexts. The N170 and P300 components at occipital sites and the frontal slow wave manifested SMEs that were modulated by positive contexts; neither negative nor non-emotional contexts influenced these effects. The behavioral and neurophysiological data demonstrated that positive contexts are stronger predictors of episodic memory than negative or non-emotional contexts.

Imbalance in habitual versus goal directed neural systems during symptom provocation in obsessive-compulsive disorder

Intrusive thoughts and compulsive urges to perform stereotyped behaviours are typical symptoms of obsessive-compulsive disorder. Emerging evidence suggests a cognitive bias towards habit formation at the expense of goal-directed performance in obsessive-compulsive disorder. In this study, we test this hypothesis using a novel individualized ecologically valid symptom provocation design: a live provocation functional magnetic resonance imaging paradigm with synchronous video-recording of behavioural avoidance responses. By pairing symptom provocation with online avoidance responses on a trial-by-trial basis, we sought to investigate the neural mechanisms leading to the compulsive avoidance response. In keeping with the model of habit formation in obsessive-compulsive disorder, we hypothesized that this disorder would be associated with lower activity in regions implicated in goal-directed behaviours and higher activity in regions implicated in habitual behaviours. Fifteen patients with obsessive-compulsive disorder and 15 healthy control volunteers participated in this functional magnetic resonance imaging study. Online stimuli were individually tailored to achieve effective symptom provocation at neutral, intermediate and strong intensity levels. During the symptom provocation block, the participant could choose to reject or terminate the provoking stimuli resulting in cessation of the symptom provocation. We thus separately analysed the neural correlates of symptom provocation, the urge to avoid, rejection and relief. Strongly symptom-provoking conditions evoked a dichotomous pattern of deactivation/activation in patients, which was not observed either in control conditions or in healthy subjects: a deactivation of caudate-prefrontal circuits accompanied by hyperactivation of subthalamic nucleus/putaminal regions. This finding suggests a dissociation between regions engaged in goal-directed and habitual behaviours. The putaminal hyperactivity during patients' symptom provocation preceded subsequent deactivation during avoidance and relief events, indicating a pivotal role of putamen in regulation of behaviour and habit formation in obsessive-compulsive disorder. Effective connectivity analysis identified the ventromedial prefrontal cortex/orbitofrontal cortex as the main structure in this circuitry involved in the modulation of compulsivity in obsessive-compulsive disorder. These findings suggest an imbalance in circuitry underlying habitual and goal-directed action control, which may represent a fundamental mechanism underlying compulsivity in obsessive-compulsive disorder. Our results complement current models of symptom generation in obsessive-compulsive disorder and may enable the development of future therapeutic approaches that aim to alleviate this imbalance.