Can neuroimaging help us to understand and classify somatoform disorders? A systematic and critical review

Frontal alpha asymmetry is associated with chronic stress and depression, but not with somatoform disorders

Cardinal characteristics of somatoform disorders (SFDs) are worry of illness, and impaired affective processing. We used relative frontal alpha asymmetry (FAA), a method to measure functional lateralization of affective processing, to investigate psychobiological correlates of SFDs. With alpha activity being inversely related to cortical network activity, relative FAA refers to alpha activity on the right frontal lobe minus alpha activity on the left frontal lobe. Less relative left frontal activity, reflected by negative FAA scores, is associated with lower positive and greater negative affectivity, such as observed in depression. Due to its negative affective component (illness anxiety), we expected to find less relative left frontal activity pattern in SFDs, and positive associations with self-reported chronic stress and depression symptoms. We recorded resting-state EEG activity with 64 electrodes, placed in a 10-10 system in 26 patients with a primary SFD, 23 patients with a major depressive disorder and 25 healthy control participants. The groups did not differ in FAA. Nevertheless, across all participants, less relative left frontal activity was associated with chronic stress and depression symptoms. We concluded that FAA may not serve as an indicator of SFDs. As the relationship of FAA and depressive symptoms was fully mediated by chronic stress, future studies have to clarify whether the association between FAA and chronic stress may represent a shared underlying factor for the manifestation of mental health complaints, such as depression.

Individual Differences in Pain Catastrophizing and Regional Gray Matter Volume Among Community-dwelling Adults With Chronic Pain: A Voxel-based Morphology Study

OBJECTIVES

Elevations in pain catastrophizing (PC) are associated with more severe pain, emotional distress, and impairment within samples with chronic pain. However, brain structure correlates underlying individual differences in PC are not well understood and predict more severe pain and impairment within samples with chronic pain. This study assessed links between regional gray matter volume (GMV) and individual differences in PC within a large mixed chronic pain sample.

MATERIALS AND METHODS

Chinese adult community dwellers with chronic pain of at least 3 months duration (101 women and 59 men) completed self-report measures of background characteristics, pain severity, depression, and a widely validated PC questionnaire as well as a structural magnetic resonance imagining scan featuring voxel-based morphology to assess regional GMV correlates of PC.

RESULTS

After controlling for demographic correlates of PC, pain severity, and depression, higher PC scores had a significant, unique association with lower GMV levels in the inferior temporal area of the right fusiform gyrus, a region previously implicated in emotion regulation.

DISCUSSION

GMV deficits, particularly in right temporal-occipital emotion regulation regions, correspond to high levels of PC among individuals with chronic pain.

Pediatric Functional Neurological Symptoms Disorder: Walking Ability and Perceived Exertion Post-Pediatric Rehabilitation

BACKGROUND

Adolescents with functional neurological symptoms disorder (FNSD) commonly present walking abnormalities. Walking is influenced by 'objective' (e.g., fitness) and 'subjective' (e.g., fear) components. Rate of perceived exertion (RPE) reflects the interaction between these two components. This study compared the walking ability and RPE before and after rehabilitation of adolescents with FNSD to adolescents with moderate-to-severe traumatic brain injury (TBI). Factors predicting walking and RPE were also examined.

METHODS

Adolescents with FNSD (n = 31) and adolescents with moderate-to-severe TBI (n = 28) aged 6 to 18 years participated in the study. Participants received a multidisciplinary rehabilitation program. Six-minute walk test (6MWT) and RPE were assessed before and after rehabilitation.

RESULTS

At pre-test, the TBI group presented lower RPE than the FNSD group (3.38 ± 2.49 and 6.25 ± 2.71, respectively). In the FNSD group, pre-test 6MWT was a significant predictor of post-test 6MWT (adjusted R2 = 0.17; p = 0.01). In the TBI group, post-test 6MWT was significantly predicted by both the pre-test 6MWT and age (adjusted R2 = 0.16; p = 0.04).

CONCLUSIONS

Prior to the intervention, adolescents with FNSD perceived walking as a more difficult activity than adolescents with TBI. Post-intervention, although the intervention was effective in terms of changes in 6MWT and RPE, the 'subjective' component still contributed to the elevated RPE of the FNSD group.

Clinical Manifestations of Body Memories: The Impact of Past Bodily Experiences on Mental Health

Bodily experiences such as the feeling of touch, pain or inner signals of the body are deeply emotional and activate brain networks that mediate their perception and higher-order processing. While the ad hoc perception of bodily signals and their influence on behavior is empirically well studied, there is a knowledge gap on how we store and retrieve bodily experiences that we perceived in the past, and how this influences our everyday life. Here, we explore the hypothesis that negative body memories, that is, negative bodily experiences of the past that are stored in memory and influence behavior, contribute to the development of somatic manifestations of mental health problems including somatic symptoms, traumatic re-experiences or dissociative symptoms. By combining knowledge from the areas of cognitive neuroscience and clinical neuroscience with insights from psychotherapy, we identify Clinical Body Memory (CBM) mechanisms that specify how mental health problems could be driven by corporeal experiences stored in memory. The major argument is that the investigation of the neuronal mechanisms that underlie the storage and retrieval of body memories provides us with empirical access to reduce the negative impact of body memories on mental health.

MRI Study of Cerebral Cortical Thickness in Patients with Herpes Zoster and Postherpetic Neuralgia

Objective

To measure the changes in cerebral cortical thickness in patients with herpes zoster (HZ) and postherpetic neuralgia (PHN) by surface-based morphometry (SBM) and further estimate its correlation with clinical scores.

Materials and Methods

Twenty-nine HZ patients, 30 PHN patients and 30 well-matched healthy controls (HCs) were included. Magnetic resonance imaging (MRI) data from all subjects were collected and then analyzed by SBM. The changes in cortical thickness among the HZ, PHN and HC groups were analyzed by ANOVA and correlated with clinical scores.

Results

The thickness of the bilateral primary visual cortex (V1, V2) and right primary visual cortex (V3), left somatosensory cortex (L3A), right anterior cingulate gyrus and medial prefrontal cortex (RS32) increased in PHN group, and the thickness the left insular and frontal opercular cortex (LFOP4), left motor cortex (L3B), and right superior temporal visual cortex (RSTV) were decreased in the HZ and PHN groups compared to the HC group. The thickness measurements of RS32, LFOP4, and (L3B) in HZ and PHN patients were correlated with the duration of disease. In HZ and PHN patients, the Hamilton Anxiety Scale (HAMA) and Hamilton Depression Scale (HAMD) scores were significantly positively correlated.

Conclusion

Changes in cortical thickness in the areas related to sensory, motor, and cognitive/emotional changes in patients with PHN affect the neuroplasticity process of the brain, which may be the reason for the transformation of HZ into PHN and provide a possible explanation for the neuropathological mechanism of pain persistence in PHN patients.

Bilateral Anterior Capsulotomy for the Treatment of Refractory Somatic Symptom Disorder: A Case Report

Somatic symptom disorder (SSD) is a form of mental illness that causes one or more distressing somatic symptoms leading to a significant disruption to everyday life, characterized by excessive thoughts, feelings, or behaviors related to these symptoms. While SSD is characterized by significant discomfort in some parts of the body, these symptoms are not related to any known medical condition and therefore it cannot be diagnosed using any medical instrument examination. Currently available treatments for SSD, including drug therapy and psychotherapy (such as cognitive behavioral therapy), usually improve psychiatric symptoms, but the results are often disappointing. Furthermore, SSD is often comorbid with anxiety and depression (75.1 and 65.7%, respectively). Importantly, interventions targeting the anterior limb of the internal capsule (ALIC; e.g., deep brain stimulation and thermal ablation) can effectively treat various mental disorders, such as refractory obsessive-compulsive disorder, depression, and eating disorders, suggesting that it may also be effective for treating the depressive symptoms associated with SSD comorbidity. In this report, a 65-year-old woman diagnosed with SSD accompanied with depression and anxiety underwent bilateral anterior capsulotomy. The patient complained of nausea and vomiting, swelling of the hilum of the liver for 14 years, weakness of the limbs for 13 years, and burning pain in the esophagus for 1 year. Psychiatric and neuropsychological assessments were conducted to record the severity of the patients' symptoms and the progression of postoperative symptoms. The patient's somatization, depression, and anxiety symptoms as well as quality of life improved significantly and steadily; thus, anti-depressive and anti-anxiety medication were stopped. However, the patient developed new somatization symptoms, including dizziness, headache, and sternal pain, 10 months after the operation. Therefore, the patient resumed taking flupentixol and melitracen in order to control the new symptoms. This study shows that bilateral anterior capsulotomy appears to be a complementary treatment for refractory SSD with depressive and anxiety symptoms. Furthermore, postoperative use of anxiolytic and antidepressant medications may be useful for controlling future somatization symptoms.

Comparison of brain activity within the sensorimotor network between sports players and patients with somatic symptom disorder

OBJECTIVE

We aimed to identify differences in brain functional connectivity (FC) and characteristics of body sensation between sports players and patients with somatic symptom disorder (SSD), in order to investigate the neurobiological basis of SSD.

METHODS

Thirty-five sports players (SPORTS group), 36 patients with SSD (SOM group), and 33 healthy control participants (HC group) underwent resting-state functional magnetic resonance imaging. We used a seed-based FC analysis.

RESULTS

Both groups showed increased brain activity in the left precuneus. The level of body intelligence in the SPORTS group and the level of somatosensory amplification in the SOM group were positively correlated with brain activity in the left precuneus. The SPORTS group showed increased FC between the left precuneus and the right/left insula compared to the HC group. The SOM group showed increased FC between the left precuneus and the right parahippocampal gyrus compared to the HC group. The SPORTS group showed increased FC between the left precuneus and left posterior cingulate gyrus compared to the SOM group.

CONCLUSION

Increased FC between the precuneus within the default mode network (DMN) and the insula connected to the sensorimotor network in sports players may be related to better somatosensory functions. In contrast, increased FC between the precuneus of the DMN and the parahippocampal gyrus of the affective network in SSD may be associated with dysfunctional processing and misconception of information. Future studies should examine whether treatments for improving affective processing normalize the affective network, and if this is correlated with somatic symptom improvement.

Structural neuroimaging of somatoform disorders: A systematic review

Although there has been an increment in neuroimaging research in somatoform disorders (SD), to date little is known about the neural correlates of these diseases. Therefore, in this systematic, review we aimed at summarizing the existing evidence of structural brain alterations in SD as per DSM-IV and DSM-5 criteria. Three electronic databases (Scopus, PubMed and Web of Science) were searched. Only case-control studies using structural neuroimaging were included. Forty-five out of 369 articles fulfilled inclusion criteria and were reviewed. Compared to controls, subjects with SD showed morphological alterations encompassing motor, limbic and somatosensory circuits. Although far from being conclusive, the results suggested that SD are characterized by selective alterations of large-scale brain networks implicated in cognitive control, emotion regulation and processing, stress and somatic-visceral perception. This review highlights the need for further multimodal neuroimaging studies with longitudinal designs, in larger and better-characterized samples, to elucidate the temporal and causal relationship between neuroanatomical changes and SD, which is paramount for informing tailored treatments.

Understanding persistent physical symptoms: Conceptual integration of psychological expectation models and predictive processing accounts

Persistent physical symptoms (PPS) are distressing, difficult to treat, and pose a major challenge to health care providers and systems. In this article, we review two disparate bodies of literature on PPS to provide a novel integrative model of this elusive condition. First, we draw on the clinical-psychological literature on the role of expectations to suggest that people with PPS develop dysfunctional expectations about health and disease that become increasingly immune to disconfirmatory information (such as medical reassurance) through cognitive reappraisal. Second, we invoke neuroscientific predictive processing accounts and propose that the psychological process of 'cognitive immunization' against disconfirmatory evidence corresponds, at the neurobiological and computational level, to too much confidence (i.e. precision) afforded to prior predictions. This can lead to an attenuation of disconfirming sensory information so that strong priors override benign bodily signals and make people believe that something serious is wrong with the body. Combining these distinct accounts provides a unifying framework for persistent physical symptoms and shifts the focus away from their causes to the sustaining mechanisms that prevent symptoms from subsiding spontaneously. Based on this integrative model, we derive new avenues for future research and discuss implications for treating people with PPS in clinical practice.

When it hurts even more: The neural dynamics of pain and interpersonal emotions

OBJECTIVE

Chronic pain is highly prevalent among patients with mood, anxiety, personality, and somatic symptom disorders; and patients with chronic pain often suffer from persistent interpersonal distress. However, the neural mechanisms underlying this phenomenon and its possible role in the etiology of chronic pain are not yet understood. Based on our Developmental Theory of Centralized/Somatoform Pain, and prior research suggesting the existence of a shared neural system subserving interpersonal emotions and pain, we aimed to identify the neural basis for modulation of pain by feelings of interpersonal rejection and the role of the early interpersonal environment in development of this shared neural system.

METHODS

During fMRI scanning, 22 healthy participants received moderately painful thermal stimuli in 3 interpersonal contexts: Acceptance, Rejection, and Reacceptance (modified Cyberball paradigm). Early interpersonal environment was assessed using the Parental Bonding Instrument.

RESULTS

Interpersonal context modulated activity in pain neural systems during rejection and during accepting interactions with previously rejecting others. Moreover, the subjective perception of rejection, even when rejection was not occurring, correlated positively with reported pain severity and neural activity in the insula. The magnitude of neural modulation in pain circuits by feelings of rejection was associated with the quality of early interpersonal experience with caregivers.

CONCLUSIONS

Results suggest that interpersonal emotions play an important role in the development and functioning of the pain system, supporting our Developmental Theory of predisposition to chronic centralized pain. These findings have direct implications for clinical practice, including the importance of treating interpersonal distress to alleviate pain.

Somatic symptoms disorders in Parkinson's disease are related to default mode and salience network dysfunction

Background

Somatic Symptoms Disorder (SSD) has been shown to have a clinically very high prevalence in Parkinson's Disease (PD) with frequencies ranging from 7.0% to 66.7%, higher than in the general population (10%- 25%).

SSD has been associated with dysfunction in Default Mode and Salience network.

Aim

With the present study we aim to verify by means of resting state functional MRI whether possible specific abnormalities in the activation and functional connectivity of the default mode network (DMN) and salience network in cognitively intact PD patients may be more prominent in PD patients with somatic symptoms (SSD-PD) as compared with patients without SSD (PD).

Methods

Eighteen SSD-PD patients (61% male), 18 PD patients (83% male) and 22 healthy age-matched subjects (59% male) were enrolled in the study and underwent resting state functional MRI.

Results

fractional amplitude of low-frequency fluctuation (fALFF) showed reduced activity in bilateral lateral parietal cortex and in left anterior insula in both SSD-PD and PD compared to control group. Functional connectivity (FC) values in the DMN areas and between DMN and salience network areas were found to be lower in SSD-PD than in control group and PD. No significant correlation was found between fMRI results and demographic and clinical variables, excluding the effect of possible confounders on fMRI results.

The present study, showing reduced activity in bilateral parietal areas and in the left anterior insula as compared to healthy controls, suggests a dysfunction of the DMN and salience network in PD, either with or without SSD.

The FC reduction within DMN areas and between DMN and salience network areas in SSD-PD patients suggests a role of dysfunctional connectivity in the resting state network of patients with SSD.

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Reduced activity in parietal areas and in anterior insula in Parkinson's Disease.

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Functional connectivity is lower in Parkinson's disease with somatic symptoms.

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Somatic Symptoms in PD are related to default mode and salience network alterations.

Brain Functional Connectivity in Patients With Somatic Symptom Disorder

OBJECTIVE

The aim of the study was to evaluate whether individuals with somatic symptom disorder (SSD) display increased resting-state functional connectivity (FC) within and between the sensorimotor network (SMN), default mode network (DMN), salience network, and dorsal attention network (DAN).

METHODS

Eighteen patients with SSD and 20 age- and sex-matched healthy control participants underwent resting-state functional magnetic resonance imaging. We used a seed-based correlation approach for the four brain networks.

RESULTS

Patients with SSD had higher scores on the Somato-Sensory Amplification Scale (z = 5.22, p < .001) and Symptom Checklist-90-Revised-Somatization (z = 4.94, p < .001) and greater FC within the SMN, DMN, and salience network than healthy control participants. Patients with SSD also had increased FC between the SMN and DMN, SMN and salience network, SMN and DAN, and salience network and DAN (t = 5.10-7.47, all false discovery rate q < .05). The Somato-Sensory Amplification Scale scores correlated with FC between the SMN and salience network and between the SMN and DAN (r = .61-.82, all p < .003).

CONCLUSIONS

Based on the results of the FC analysis between the SMN and salience network, we suggest that SSD may be associated with alterations of sensory-discriminative processing of pain and other somatic symptoms, which is influenced by affective processing. Based on the results of the FC analysis of the SMN and DAN, we suggest that patients with SSD have a deficit in attention, leading to misperception of external stimuli and failure to regulate bodily functions aimed at interactions with external stimuli.

The prognosis and changes of regional brain gray matter volume in MDD with gastrointestinal symptoms

Objective: It is common that major depressive disorder (MDD) is accompanied by gastrointestinal (GI) symptoms. However, few studies have focused on the clinical characteristics and its possible mechanism, while brain gray matter (GM) structure is important in the pathogenesis of GI symptoms. In this study, we aimed to investigate the basic clinical characteristics and regional GM volume changes in MDD accompanied by GI symptoms. Method: Patients with MDD (n=49) and age, gender, and educational level-matched healthy controls (n=30) were recruited. Patients with MDD were divided into two groups based on the GI status: MDD with (n=27) and without (n=22) GI symptoms. The 24-item Hamilton Depression Rating Scale (HAMD) was administered. T1-weighted anatomical images were obtained and analyzed. Correlation analysis was used to identify the possible associations between changed regional GM volume and GI symptoms and depressive symptoms. Results: The HAMD reductive ratio for 2 weeks of treatment in the GI symptoms group was significantly higher than the non-GI symptoms group (P<0.05). The regional GM volume showed significant differences among the three groups (Gaussian Random Field [GRF] correction, voxel-P<0.01, cluster-P <0.05). Compared with non-GI symptoms group, GI symptoms group exhibited significantly increased GM volume in the left hippocampus, left parahippocampal gyrus, right parahippocampal gyrus; and decreased GM volume in the right middle frontal gyrus, right precentral gyrus, right cuneus, right precuneus, right superior occipital gyrus (GRF correction, voxel-P <0.01, cluster-P <0.05). These altered brain areas were correlated with the GI symptoms, not depressive symptoms. Conclusion: The changed regional brain GM volume in GI-MDD group may be the pathogenesis for the GI symptoms. In addition, the GI symptoms may predict the prognosis of MDD.

Increased Nucleus Accumbens Connectivity in Resting-State Patients With Drug-Naive, First-Episode Somatization Disorder

The nucleus accumbens (NAc) plays an important role in the reward circuit, and abnormal regional activities of the reward circuit have been reported in various psychiatric disorders including somatization disorder (SD). However, few researches are designed to analyze the NAc connectivity in SD. This study was designed to explore the NAc connectivity in first-episode, drug-naive patients with SD using the bilateral NAc as seeds. Twenty-five first-episode, drug-naive patients with SD and 28 healthy controls were recruited. Functional connectivity (FC) was designed to analyze the images. LIBSVM (a library for support vector machines) was used to identify whether abnormal FC could be utilized to discriminate the patients from the controls. The patients showed significantly increased FC between the left NAc and the right gyrus rectus and left medial prefrontal cortex/anterior cingulate cortex (MPFC/ACC), and between the right NAc and the left gyrus rectus and left MPFC/ACC compared with the controls. The patients could be separated from the controls through increased FC between the left NAc and the right gyrus rectus with a sensitivity of 88.00% and a specificity of 82.14%. The findings reveal that patients with SD have increased NAc connectivity with the frontal regions of the reward circuit. Increased left NAc-right gyrus rectus connectivity can be used as a potential marker to discriminate patients with SD from healthy controls. The study thus highlights the importance of the reward circuit in the neuropathology of SD.

Cortical Thickness Alterations in Chronic Pain Disorder: An Exploratory MRI Study

OBJECTIVE

Chronic pain disorder (CPD) has been associated with brain changes, especially in limbic circuits. However, in most patients with chronic pain, depression or anxiety is a common comorbidity. In this exploratory and naturalistic study, we investigated brain cortical thickness (CTh) differences between patients with CPD and healthy controls, with consideration of concurrent psychiatric symptoms.

METHODS

Twenty-three patients with CPD and 23 age- and sex-matched healthy volunteers were included in this study. CTh was estimated using Freesurfer on high-resolution three-dimensional T1-weighted images acquired with a 3T scanner. Group differences were investigated using an analysis of covariance model that included age, sex, and Beck Depression Inventory I and Trait Anxiety Inventory scores as covariates. The relationship between CTh and Toronto Alexithymia Scale (TAS-20) scores was also investigated in patients. Data were corrected for multiplicity using the False Discovery Rate approach (q < .05).

RESULTS

The comparison between groups using demographics and Beck Depression Inventory I scores as covariates showed thinner cortex in patients compared with controls, after correction for multiplicity in the left precentral (F(1,42) = 21.9, p < .05) and postcentral gyri (F(1,42) = 26.9, p < .05) and in the left inferior temporal sulcus (F(1,42) = 19.6, p < .05). Moreover, using the Trait Anxiety Inventory as covariate, a trend toward significance (p < .001 uncorrected) was seen for the left precentral gyrus (F(1,42) = 13.8), right middle frontal (F(1,42) = 14.3) and inferior parietal gyri (F(1,42) = 13.4), and right anterior temporal pole (F(1,42) = 15.9).

CONCLUSIONS

The results indicate that brain morphological differences between patients with chronic pain disorder and healthy controls are localized to regions that correspond to sensory as well as affective dimensions of pain processing.

Increased coherence-based regional homogeneity in resting-state patients with first-episode, drug-naive somatization disorder

BACKGROUND

Abnormal neural activity has been observed in patients with somatization disorder (SD), especially in brain regions of the default-mode network (DMN). In this study, a coherence-based regional homogeneity (Cohe-ReHo) approach was used to detect abnormal regional synchronization in patients with SD, which might be used to differentiate the patients from the controls.

METHODS

We recruited 25 patients with SD and 28 healthy controls. The imaging data of the participants were analyzed using the Cohe-ReHo approach. LIBSVM (a library for support vector machines) was utilized to verify whether abnormal Cohe-ReHo values could be applied to separate patients with SD from healthy controls.

RESULTS

Compared with healthy controls, patients with SD showed an increased Cohe-ReHo in the left medial prefrontal cortex/anterior cingulate cortex (MPFC/ACC) (t = 5.5017, p < 0.001). No correlations were detected between the increased Cohe-ReHo values and clinical variables of the patients. The Cohe-ReHo values in the left MPFC/ACC could be applied to distinguish patients from controls with a sensitivity and a specificity of 84.00% and 85.71%, respectively.

CONCLUSIONS

An increased Cohe-ReHo was observed in the anterior DMN of the patients and could be applied as a marker to distinguish patients from healthy controls. These results highlighted the importance of the DMN in the pathophysiology of SD.

Fatigue Is Associated With Altered Monitoring and Preparation of Physical Effort in Patients With Chronic Fatigue Syndrome

BACKGROUND

Chronic fatigue syndrome (CFS) is characterized by disabling fatigue, which is suggested to be maintained by dysfunctional beliefs. Fatigue and its maintenance are recently conceptualized as arising from abnormally precise expectations about bodily inputs and from beliefs of diminished control over bodily states, respectively. This study used functional neuroimaging to identify the neural correlates of fatigue and its maintenance by beliefs during a physical effort task.

METHODS

We isolated behavioral adjustments and cerebral activity during feedback processing and motor preparation, in the context of a task in which patients with CFS (n = 85) and healthy control subjects (n = 29) produced 30%, 50%, and 70% of their right-hand maximal voluntary contraction, and received directional feedback on performance (e.g., too little force).

RESULTS

Patients with CSF showed an effort-dependent behavioral bias toward less effort investment in response to directional feedback for the highest effort level as compared with healthy control subjects. This bias was associated with reduced feedback-related activity in the dorsolateral prefrontal cortex. These effects were proportional to state-related fatigue and prior beliefs about CFS patients' ability to perform the task. Patients with CFS also showed higher activity in the supplementary motor area, proportional to their state-related fatigue, and reduced connectivity between the supplementary motor area and sensorimotor cortex during motor preparation as compared with control subjects.

CONCLUSIONS

These findings link fatigue symptoms to alterations in behavioral choices on effort investment, prefrontal functioning, and supplementary motor area connectivity, with the dorsolateral prefrontal cortex being associated with prior beliefs about physical abilities.

Emotion regulation strategies in trauma-related disorders: pathways linking neurobiology and clinical manifestations

Emotion regulation impairments with traumatic origins have mainly been studied from posttraumatic stress disorder (PTSD) models by studying cases of adult onset and single-incident trauma exposure. The effects of adverse traumatic experiences, however, go beyond the PTSD. Different authors have proposed that PTSD, borderline personality, dissociative, conversive and somatoform disorders constitute a full spectrum of trauma-related conditions. Therefore, a comprehensive review of the neurobiological findings covering this posttraumatic spectrum is needed in order to develop an all-encompassing model for trauma-related disorders with emotion regulation at its center. The present review has sought to link neurobiology findings concerning cortico-limbic function to the field of emotion regulation. In so doing, trauma-related disorders have been placed in a continuum between under- and over-regulation of affect strategies. Under-regulation of affect was predominant in borderline personality disorder, PTSD with re-experiencing symptoms and positive psychoform and somatoform dissociative symptoms. Over-regulation of affect was more prevalent in somatoform disorders and pathologies characterized by negative psychoform and somatoform symptoms. Throughout this continuum, different combinations between under- and over-regulation of affect strategies were also found.

Altered regional brain function in the treatment-naive patients with somatic symptom disorder: a resting-state fMRI study

INTRODUCTION

Somatic symptom disorder (SSD) is an illness that occurs over a long time and results in significant disruption in daily life. Clinically, SSD patients typically express complaints that involve a variety of organ systems. However, the neural mechanism of SSD remains poorly understood.

METHODS

Using resting-state functional magnetic resonance imaging, we investigated the characteristics of the regional basal brain function during resting state in patients with SSD. Eleven treatment-naïve SSD patients and 12 age-matched healthy controls were recruited in this study. Between-group differences in regional homogeneity values were analyzed.

RESULTS

Compared with the healthy control group, the SSD group showed significant increases in regional homogeneity values in the right medial prefrontal cortex, anterior cingulate cortex and supramarginal gyrus, and significant decreases in the bilateral middle occipital gyrus, superior occipital gyrus and right cuneus and left postcentral gyrus and cerebellum. Meanwhile, the regional homogeneity value of the right medial prefrontal cortex positively correlated with the total duration of SSD.

CONCLUSIONS

The abnormal resting-state patterns in regional brain activity may contribute to understanding the mechanism of SSD.

Magnitude and variability of effect sizes for the associations between chronic pain and cognitive test performances: a meta-analysis

OBJECTIVES AND METHODS

A systematic review and meta-analysis were performed to estimate the size and variability of the association between chronic pain (CP) and poorer cognitive test performances as a function of individual tests, pain sub-types, and study sources on 22 studies having (1) a control group, (2) reported means and standard deviations (SDs) and (3) tests studied at least 3 times.

RESULTS

CP patients performed significantly poorer with small to moderate effects (d = -.31 to -.57) on Digit Span Backward; STROOP Word; Color and Color-Word; Digit Symbol; Trail Making A and B; Rey Auditory Learning Immediate and Delayed Recall and Recognition. For these 10 measures, single effects (no interaction) were supported (I(2) = 0%-8%) and Random and Fixed models yielded similar results. No group differences were found for Corsi Blocks Forward or Wisconsin Cart Sorting Test Categories Achieved, or Perseveration. Effects for the Rey Complex Figure Immediate and Delayed Recall were significant, but effect size was inconclusive, given moderate to high heterogeneity and lack of consistency between Random and Fixed models. For the Paced Auditory Serial Addition Test, there was a homogeneous (I(2) = 0%) and significantly lower performance in fibromyalgia (d = -.47), but no effect in diagnostically undifferentiated pain samples, and wide variability across studies of whiplash (d = -.15 to -1.04, I(2) = 60%).

CONCLUSION

The magnitude and consistency of the CP - cognition effect depended on the test, pain subgroup and study source.

SUMMARY POINTS

Among tests showing a chronic pain (CP) - cognition effect, the magnitude of this association was consistently small to moderate across tests.Effect size estimation was inconclusive for Digit Span Forwards, the Paced Auditory Serial Addition Test and the Rey Complex Figure Test.Variance was too heterogeneous for testing cognitive domain specificity of the CP - cognition effect.

Clinical significance of increased cerebellar default-mode network connectivity in resting-state patients with drug-naive somatization disorder

The cerebellum has been proven to be connected to the brain network, as in the default-mode network (DMN), among healthy subjects and patients with psychiatric disorders. However, whether or not abnormal cerebellar DMN connectivity exists and what its clinical significance is among drug-naive patients with somatization disorder (SD) at rest remain unclear.A total of 25 drug-naive patients with SD and 28 healthy controls were enrolled for a resting-state scan. The imaging data were analyzed using the seed-based functional connectivity (FC) method.Compared with the controls, patients with SD showed increased left/right Crus I-left/right angular gyrus (AG) connectivity and Lobule IX-left superior medial prefrontal cortex (MPFC) connectivity. The FC values of the left/right Crus I-right AG connectivity of the patients were positively correlated with their scores in the somatization subscale of the symptom checklist-90 (Scl-90). A trend level of correlations was observed between the FC values of the left Crus I-left AG connectivity of the patients and their scores for the somatization subscale of Scl-90, as well as between the FC values of their Lobule IX-left superior MPFC connectivity and their scores for the Eysenck personality questionnaire (EPQ) extraversion.Our findings show the increased cerebellar DMN connectivity in patients with SD and therefore highlight the importance of the DMN in the neurobiology of SD. Increased cerebellar DMN connectivities are also correlated with their somatization severity and personality, both of which bear clinical significance.

The Mental Health of Older Persons After Human-Induced Disasters: A Systematic Review and Meta-Analysis of Epidemiological Data

BACKGROUND

Older people are increasingly "in harm's way" following human-induced disasters (HIDs). There is debate in the literature as to the relative impact of disasters on their psychological health compared with other age groups. Natural disasters and HIDs are thought to affect survivors differentially, and this may extend to older adults as a group. In the absence of existing systematic reviews, we aimed to synthesize the available evidence and conduct meta-analyses of the effects of HIDs on the psychological health of older versus younger adults.

METHODS

A meta-analysis was conducted on papers identified through a systematic review. The primary outcomes measured were post-traumatic stress disorder (PTSD), depression, anxiety disorders, adjustment disorder, and psychological distress.

RESULTS

We identified 11 papers from 10 studies on HIDs (N = 26,753), of which 8 had sufficient data for a random-effects meta-analysis. Older adults were 2.85 times less likely to experience PTSD symptoms following HID (95% CI: 1.42-5.70) when compared with younger adults. There was no statistically significant difference in terms of anxiety and depressive symptoms.

CONCLUSION

Health and emergency services need to be increasingly prepared to meet the psychological needs of older people, given the global rise in the numbers of older adults affected by disasters of all kinds. Preliminary evidence suggests that old age may be a protective factor for the development of PTSD in the wake of HID.

Preinjury somatization symptoms contribute to clinical recovery after sport-related concussion

OBJECTIVE

To determine the degree to which preinjury and acute postinjury psychosocial and injury-related variables predict symptom duration following sport-related concussion.

METHODS

A total of 2,055 high school and collegiate athletes completed preseason evaluations. Concussed athletes (n = 127) repeated assessments serially (<24 hours and days 8, 15, and 45) postinjury. Cox proportional hazard modeling was used to predict concussive symptom duration (in days). Predictors considered included demographic and history variables; baseline psychological, neurocognitive, and balance functioning; acute injury characteristics; and postinjury clinical measures.

RESULTS

Preinjury somatic symptom score (Brief Symptom Inventory-18 somatization scale) was the strongest premorbid predictor of symptom duration. Acute (24-hour) postconcussive symptom burden (Sport Concussion Assessment Tool-3 symptom severity) was the best injury-related predictor of recovery. These 2 predictors were moderately correlated (r = 0.51). Path analyses indicated that the relationship between preinjury somatization symptoms and symptom recovery was mediated by postinjury concussive symptoms.

CONCLUSIONS

Preinjury somatization symptoms contribute to reported postconcussive symptom recovery via their influence on acute postconcussive symptoms. The findings highlight the relevance of premorbid psychological factors in postconcussive recovery, even in a healthy athlete sample relatively free of psychopathology or medical comorbidities. Future research should elucidate the neurobiopsychosocial mechanisms that explain the role of this individual difference variable in outcome following concussive injury.

Investigation of facial emotion recognition, alexithymia, and levels of anxiety and depression in patients with somatic symptoms and related disorders

BACKGROUND

The concept of facial emotion recognition is well established in various neuropsychiatric disorders. Although emotional disturbances are strongly associated with somatoform disorders, there are a restricted number of studies that have investigated facial emotion recognition in somatoform disorders. Furthermore, there have been no studies that have regarded this issue using the new diagnostic criteria for somatoform disorders as somatic symptoms and related disorders (SSD). In this study, we aimed to compare the factors of facial emotion recognition between patients with SSD and age- and sex-matched healthy controls (HC) and to retest and investigate the factors of facial emotion recognition using the new criteria for SSD.

PATIENTS AND METHODS

After applying the inclusion and exclusion criteria, 54 patients who were diagnosed with SSD according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria and 46 age- and sex-matched HC were selected to participate in the present study. Facial emotion recognition, alexithymia, and the status of anxiety and depression were compared between the groups.

RESULTS

Patients with SSD had significantly decreased scores of facial emotion for fear faces, disgust faces, and neutral faces compared with age- and sex-matched HC (t=-2.88, P=0.005; t=-2.86, P=0.005; and t=-2.56, P=0.009, respectively). After eliminating the effects of alexithymia and depressive and anxious states, the groups were found to be similar in terms of their responses to facial emotion and mean reaction time to facial emotions.

DISCUSSION

Although there have been limited numbers of studies that have examined the recognition of facial emotion in patients with somatoform disorders, our study is the first to investigate facial recognition in patients with SSD diagnosed according to the DSM-5 criteria. Recognition of facial emotion was found to be disturbed in patients with SSD. However, our findings suggest that disturbances in facial recognition were significantly associated with alexithymia and the status of depression and anxiety, which is consistent with the previous studies. Further studies are needed to highlight the associations between facial emotion recognition and SSD.

Evaluation of oxidant, antioxidant, and S100B levels in patients with conversion disorder

INTRODUCTION

Various psychodynamic, neurobiological, genetic, and sociocultural factors are believed to be involved in the etiology of conversion disorder (CD). Oxidative metabolism has been shown to deteriorate in association with many health problems and psychiatric disorders. We evaluated oxidative metabolism and S100B levels in the context of this multifactorial disease.

METHODS

Thirty-seven patients with CD (25 females and 12 males) and 42 healthy volunteers (21 females and 21 males), all matched for age and sex, were included in this study. The total oxidant status, total antioxidant status, oxidative stress index, and S100B levels were compared between the two groups.

RESULTS

The total oxidant status, oxidative stress index, and S100B levels were significantly higher in patients with CD than in the control group, whereas the total antioxidant status was significantly lower.

CONCLUSION

CD is associated with deterioration of oxidative metabolism and increased neuronal damage.

Présent et avenir des troubles somatoformes

Dans le DSM-IV, les « troubles somatoformes » étaient définis négativement par la présence de symptômes somatiques « médicalement inexpliqués ». Cette appellation a disparu du DSM-V au profit des somatic symptoms and related disorders. Les troubles somatisation, douloureux, somatoforme indifférencié et l’hypocondrie, lorsqu’elle est associée à des symptômes somatiques, sont regroupés sous l’appellation unique de somatic symptom disorder. Ce trouble est désormais défini positivement par la présence de pensées, émotions ou comportements « excessifs ou inappropriés », à l’origine d’un retentissement fonctionnel ou d’une souffrance subjective et accompagnant des symptômes somatiques ayant, ou non, une cause somatique identifiée. Les raisons de ce changement sont le recouvrement diagnostique des anciennes catégories, leur non-utilisation par les somaticiens, le risque de stigmatisation et le caractère intenable d’une conception dualiste des rapports corps-esprit. La notion de symptômes « médicalement inexpliqués » demeure néanmoins centrale dans la conversion, renommée « trouble neurologique fonctionnel ». Plusieurs études d’imagerie cérébrales fonctionnelles portant sur un petit nombre de patients présentant un déficit moteur unilatéral ont tenté d’élucider la physiopathologie de ce trouble. Certains résultats semblent reproductibles : hyperactivation et hypo-activation controlatérales respectivement des cortex cingulaire antérieur et moteur primaire. Ces résultats ont servi de rationnel à l’utilisation thérapeutique de la stimulation magnétique transcrânienne. L’hypocondrie sans symptômes somatiques devient dans le DSM-V « l’anxiété pour la santé », caractérisée par la crainte excessive d’avoir ou de développer une maladie. La prise en charge est souvent difficile et peut renforcer les symptômes si elle est inappropriée. Plusieurs études ont montré l’efficacité des thérapies cognitives et comportementales, basées sur la restructuration cognitive et l’extinction des comportements d’évitement, ainsi que des thérapies basées sur la pleine conscience. Compte tenu du lien fréquent entre pensées intrusives et souvenirs douloureux, la valeur ajoutée d’une thérapie des schémas est vraisemblable.

Neural substrates of conversion deafness in a cochlear implant patient: a molecular imaging study using H₂¹⁵O-PET

OBJECTIVE

Conversion deafness is characterized by sudden hearing loss without any identifiable cause. In the current study, we investigated presumed conversion deafness in a cochlear implant user using H₂¹⁵O-positron emission tomography (PET) scan with speech and noise stimuli in conjunction with audiologic tests such as impedance test and auditory response telemetry. Also, by performing a follow-up PET scan after recovery and comparing prerecovery and postrecovery scans, we attempted to find possible neural substrates of conversion deafness.

PATIENT

A 51-year-old man with conversion deafness after 4 years of successful cochlear implant use.

INTERVENTION

Supportive psychotherapy.

MAIN OUTCOME MEASURES

Prerecovery and postrecovery H₂¹⁵O-PET scans

RESULTS

The prerecovery H₂¹⁵O-PET scan revealed auditory cortex activation by sound stimuli, which verified normal stimulation of the central auditory pathway. Notably, compared with the prerecovery state, the postrecovery state showed relative activation in the right auditory cortex both under the speech and noise stimulus conditions. Moreover, the bilateral prefrontal and parietal areas were activated more in the postrecovery state than in the prerecovery state. In other words, relative deactivation of the prefronto-parieto-temporal network, a network responsible for conscious sensory perception, or relative dysfunction of top-down and bottom-up attention shifting mediated by the ventral and the dorsal parietal cortices, may have resulted in conversion deafness in the patient.

CONCLUSION

Relative deactivation of the prefronto-parieto-temporal network or dysfunction in the ventral and the dorsal parietal cortices may be related to the development of conversion deafness.

Investigating neural mechanisms of change of cognitive behavioural therapy for chronic fatigue syndrome: a randomized controlled trial

BACKGROUND

Chronic fatigue syndrome (CFS) is characterized by profound and disabling fatigue with no known somatic explanation. Cognitive behavioral therapy (CBT) has proven to be a successful intervention leading to a reduction in fatigue and disability. Based on previous neuroimaging findings, it has been suggested that central neural mechanisms may underlie CFS symptoms and play a role in the change brought on by CBT. In this randomized controlled trial we aim to further investigate the neural mechanisms that underlie fatigue in CFS and their change by CBT.

METHODS/DESIGN

We will conduct a randomized controlled trial in which we collect anatomical and functional magnetic resonance imaging (MRI) measures from female CFS patients before and after CBT (N = 60) or waiting list (N = 30) and compare these with measures from age and education matched healthy controls (N = 30). By including a large treatment group we will also be able to compare patients that benefit from CBT with those that do not. In addition, to further investigate the role of endocrine and immune biomarkers in CFS, we will determine cortisol and cytokine concentrations in blood, hair and/or saliva.

DISCUSSION

This project creates an unique opportunity to enhance our understanding of CFS symptoms and its change by CBT in terms of neuroanatomical, neurofunctional, endocrinological and immunological mechanisms and can help to further improve future treatments strategies.

TRIAL REGISTRATION

Dutch Trial Register #15852. Registered 9 December 2013 ( http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4311 ).

Abnormal regional homogeneity and its correlations with personality in first-episode, treatment-naive somatization disorder

BACKGROUND

Structural and functional abnormalities of the default mode network (DMN) and their correlations with personality have been found in somatization disorder (SD). However, no study is conducted to identify regional neural activity and its correlations with personality in SD. In this study, regional homogeneity (ReHo) was applied to explore whether abnormal regional neural activity is present in patients with SD and its correlations with personality measured by Eysenck Personality Questionnaire (EPQ).

METHODS

Twenty-five first-episode, treatment-naive patients with SD and 28 sex-, age-, and education-matched healthy controls participated in the whole study. During the scanning, all subjects were instructed to lie still with their eyes closed and remain awake. A ReHo approach was employed to analyze the data.

RESULTS

The SD group had a significantly increased ReHo in the left angular gyrus (AG) compared to healthy controls. The increased ReHo positively correlated to the neuroticism scores of EPQ (EPQ-N). No other correlations were detected between the ReHo values and other related factors, such as symptom severity and education level.

CONCLUSIONS

Our results suggest that abnormal regional neural activity of the DMN may play a key role in SD with clinical implications and emphasize the importance of the DMN in the pathophysiological process of SD.

Treating empty nose syndrome as a somatic symptom disorder

Empty nose syndrome (ENS) is a rare complication of inferior turbinate resection, characterized by a paradoxical nasal obstruction sensation despite decreased nasal resistance. Here we report the case of a 37-year-old patient with ENS and severe functional impairment, who was diagnosed with a somatic symptom disorder and treated accordingly. Cognitive behavior therapy targeting dysfunctional beliefs and avoidance behaviors together with a treatment by venlafaxine resulted in dramatic functional improvement between month 2 and month 4. At month 6, the patient was displaying back-to-normal levels of functioning and was no longer seeking care for ENS. Treating ENS as a somatic symptom disorder might constitute a first-line, safe alternative to surgical treatment.

First episode of psychosis in a middle-aged patient with a 14-year history of conversion disorder

We present a case of a middle-aged male patient with a long history of conversion disorder and histrionic personality, who presented with newly onset psychotic symptoms while being engaged to treatment with a community mental health team in a primary care setting. The symptoms could not be attributed to an organic cause. After a short course of olanzapine treatment which caused adverse effects, the symptomatology responded well to low dose amisulpride. Conversion symptoms were stable throughout the psychotic episode. This case illustrates the complex interplay between disorders classified in different categories (somatoform versus psychotic disorders).

Increased functional connectivity strength of right inferior temporal gyrus in first-episode, drug-naive somatization disorder

BACKGROUND

Evidence of brain structural and functional alterations have been implicated in patients with somatization disorder (SD). However, little is known about brain functional connectivity in SD. In the present study, resting-state functional magnetic resonance imaging (fMRI) and graph theory were used to obtain a comprehensive view of whole-brain functional connectivity and to investigate the changes of voxel-wise functional networks in patients with SD.

METHODS

Twenty-five first-episode, medication-naive patients with SD and 28 age-, sex- and education-matched healthy controls (HCs) underwent resting-state fMRI. The graph theory approach was employed to analyze the data.

RESULTS

Compared to the HCs, patients with SD showed significantly increased functional connectivity strength in the right inferior temporal gyrus (ITG). There is a significant positive correlation between the z-values of the cluster in the right ITG and Hamilton Anxiety Scale scores.

CONCLUSIONS

Our findings indicate that there is a disruption of the functional connectivity pattern in the right ITG in first-episode, treatment-naive patients with SD, which bears clinical significance.

Functional neuroimaging of conversion disorder: the role of ancillary activation

Background

Previous functional neuroimaging studies investigating the neuroanatomy of conversion disorder have yielded inconsistent results that may be attributed to small sample sizes and disparate methodologies. The objective of this study was to better define the functional neuroanatomical correlates of conversion disorder.

Methods

Ten subjects meeting clinical criteria for unilateral sensory conversion disorder underwent fMRI during which a vibrotactile stimulus was applied to anesthetic and sensate areas. A block design was used with 4 s of stimulation followed by 26 s of rest, the pattern repeated 10 times. Event-related group averages of the BOLD response were compared between conditions.

Results

All subjects were right-handed females, with a mean age of 41. Group analyses revealed 10 areas that had significantly greater activation (p < .05) when stimulation was applied to the anesthetic body part compared to the contralateral sensate mirror region. They included right paralimbic cortices (anterior cingulate cortex and insula), right temporoparietal junction (angular gyrus and inferior parietal lobule), bilateral dorsolateral prefrontal cortex (middle frontal gyri), right orbital frontal cortex (superior frontal gyrus), right caudate, right ventral-anterior thalamus and left angular gyrus. There was a trend for activation of the somatosensory cortex contralateral to the anesthetic region to be decreased relative to the sensate side.

Conclusions

Sensory conversion symptoms are associated with a pattern of abnormal cerebral activation comprising neural networks implicated in emotional processing and sensory integration. Further study of the roles and potential interplay of these networks may provide a basis for an underlying psychobiological mechanism of conversion disorder.

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fMRI was used to study subjects with unilateral sensory conversion disorder.

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Sensory stimulation of anesthetic body part compared to sensate mirror region

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10 brain regions, including right limbic cortices and TPJ, were abnormally active.

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Implicated neural networks may provide a mechanism for conversion disorder.

Dissociation of regional activity in default mode network in medication-naive, first-episode somatization disorder

Background

Patients with somatization disorder (SD) have altered neural activity in the brain regions of the default mode network (DMN). However, the regional alteration of the DMN in SD remains unknown. The present study was designed to investigate the regional alterations of the DMN in patients with SD at rest.

Methods

Twenty-five first-episode, medication-naive patients with SD and 28 age-, sex-, education- matched healthy controls underwent a resting-state functional magnetic resonance imaging (fMRI) scan. The fractional amplitude of low-frequency fluctuations (fALFF) was applied to analyze the data.

Results

Patients with SD showed a dissociation pattern of resting-state fALFF in the DMN, with increased fALFF in the bilateral superior medial prefrontal cortex (MPFC, BA8, 9) and decreased fALFF in the left precuneus (PCu, BA7). Furthermore, significantly positive correlation was observed between the z values of the voxels within the bilateral superior MPFC and somatization subscale scores of the Symptom Check List (SCL-90) in patients with SD.

Conclusions

Our findings indicate that there is a dissociation pattern of the anterior and posterior DMN in first-episode, treatment-naive patients with SD. The results provide new insight for the importance of the DMN in the pathophysiology of SD.

[Critical Approach to Somatomorphic Disorders in Children]

Somatomorphic disorders have common somatic manifestations without medical explanation, that can affect daily life. There are evaluation difficulties regarding symptom report or observation in children due to their age, parental influence and associated factors. The aim of this work is to acknowledge diagnosis difficulties and clinic tools to approach somatomorphic disorders in children. A systematic search in the information published for the last ten years was carried out. Historical evolution of the concept of somatization has generated difficulties to approach this issue. Some signs could indicate a somatomorphic disorder; however, there are very little evaluating tools for children. Currently, said tools are only based on lists of symptoms without fully answering to all questions. Somatomorphic disorders or somatic symptoms in children are still a gap to be closed.

Altered cortical swallowing processing in patients with functional dysphagia: a preliminary study

Objective

Current neuroimaging research on functional disturbances provides growing evidence for objective neuronal correlates of allegedly psychogenic symptoms, thereby shifting the disease concept from a psychological towards a neurobiological model. Functional dysphagia is such a rare condition, whose pathogenetic mechanism is largely unknown. In the absence of any organic reason for a patient's persistent swallowing complaints, sensorimotor processing abnormalities involving central neural pathways constitute a potential etiology.

Methods

In this pilot study we measured cortical swallow-related activation in 5 patients diagnosed with functional dysphagia and a matched group of healthy subjects applying magnetoencephalography. Source localization of cortical activation was done with synthetic aperture magnetometry. To test for significant differences in cortical swallowing processing between groups, a non-parametric permutation test was afterwards performed on individual source localization maps.

Results

Swallowing task performance was comparable between groups. In relation to control subjects, in whom activation was symmetrically distributed in rostro-medial parts of the sensorimotor cortices of both hemispheres, patients showed prominent activation of the right insula, dorsolateral prefrontal cortex and lateral premotor, motor as well as inferolateral parietal cortex. Furthermore, activation was markedly reduced in the left medial primary sensory cortex as well as right medial sensorimotor cortex and adjacent supplementary motor area (p<0.01).

Conclusions

Functional dysphagia - a condition with assumed normal brain function - seems to be associated with distinctive changes of the swallow-related cortical activation pattern. Alterations may reflect exaggerated activation of a widely distributed vigilance, self-monitoring and salience rating network that interferes with down-stream deglutition sensorimotor control.

Fibromyalgia syndrome: a somatoform disorder?

BACKGROUND AND OBJECTIVE

Whether fibromyalgia syndrome (FMS) can be classified as a somatoform disorder is under debate.

DATABASES AND DATA TREATMENT

Literature searches on the classification of FMS as a somatoform disorder were performed in Medline and in evidence-based guideline databases.

RESULTS

A somatoform disorder is defined by medically unexplained somatic symptoms that persist for at least 6 months and lead to a significant impairment of the ability to function in everyday life. The nature and extent of the symptoms or the distress and pre-occupation of the patient cannot be explained fully by a general medical condition or by the direct effect of a substance, and are not attributable to another mental disorder. Emotional and psychosocial conflicts play a major role in the onset, severity, exacerbation or maintenance of the physical symptoms. There is disagreement in the FMS research community on the existence of somatic factors sufficiently explaining FMS symptoms. Psychosocial factors play a major role in the onset, exacerbation or maintenance of FMS symptoms in the majority of patients. A biopsychosocial model of interacting biological and psychosocial factors in the predisposition, onset and maintenance of FMS symptoms is more appropriate than the dichotomy between a somatic disease and a mental (somatoform) disorder.

CONCLUSIONS

The clinical features of FMS and persistent somatoform pain disorder or somatization disorder according to the International Classification of Diseases (ICD)-10 overlap in individuals with chronic widespread pain without specific somatic disease factors. FMS is not synonymous with somatoform disorder.

Imaging psychogenic movement disorders

The neurobiological basis of psychogenic movement disorders (PMDs) has been elusive, and they remain difficult to treat. In the last few years, functional neuroimaging studies have provided insight into their pathophysiology and neural correlates. Here, we review the various methodological approaches that have been used in both clinical and research practice to address neural correlates of functional disorders. We then review the dominant hypotheses generated from the literature on psychogenic paralysis. Overall, these studies emphasize abnormalities in the prefrontal and anterior cingulate cortices. Recently, functional neuroimaging has been used to specifically examine PMDs. These studies have addressed a major point of controversy: whether higher frontal brain areas are directly responsible for inhibiting motor areas or whether they reflect modulation by attentional and/or emotional processes. In addition to elucidating the mechanism and cause, recent work has also explored the lack of agency that characterizes PMDs. We describe the results and implications of the results of these imaging studies and discuss possible interpretations.

Somatization severity associated with postero-medial complex structures

Somatisation is a frequent problem in various psychiatric disorders, yet the cerebral mechanisms of somatisation remain unexamined. To test if somatisation is susceptible to emotional states, we investigated relationships between somatisation severity, neural effective connectivity, and autonomic responses to emotional facial expressions. Volunteering participants (N = 20) were presented with facial expressions of happy and sad emotion at three intensity levels (0%–50%–100%) in a fast implicit ER-fMRI design with concurrent derivation of skin conductance levels (SCL). Self-reported somatisation severity as assessed with Rief's SOMS-2 index was correlated with neural response controlling for other clinical traits to ascertain brain bases of somatisation. Regression analyses estimated effective connectivity of main clusters so determined with peripheral autonomic responses. Regions in which magnitude of activity correlated with somatisation severity consisted in both happy and sad conditions of the anterior ventral precuneus (BA7), along with posterior cingulate gyrus (PCC, BA23, sad condition) and anteromedial thalamus (happy condition).

Functional network connectivity of pain-related resting state networks in somatoform pain disorder: an exploratory fMRI study

BACKGROUND

Without stimulation, the human brain spontaneously produces highly organized, low-frequency fluctuations of neural activity in intrinsic connectivity networks (ICNs). Furthermore, without adequate explanatory nociceptive input, patients with somatoform pain disorder experience pain symptoms, thus implicating a central dysregulation of pain homeostasis. The present study aimed to test whether interactions among pain-related ICNs, such as the default mode network (DMN), cingular-insular network (CIN) and sensorimotor network (SMN), are altered in somatoform pain during resting conditions.

METHODS

Patients with somatoform pain disorder and healthy controls underwent resting functional magnetic resonance imaging that lasted 370 seconds. Using a data-driven approach, the ICNs were isolated, and the functional network connectivity (FNC) was computed.

RESULTS

Twenty-one patients and 19 controls enrolled in the study. Significant FNC (p < 0.05, corrected for false discovery rate) was detected between the CIN and SMN/anterior DMN, the anterior DMN and posterior DMN/SMN, and the posterior DMN and SMN. Interestingly, no group differences in FNC were detected.

LIMITATIONS

The most important limitation of this study was the relatively short resting state paradigm.

CONCLUSION

To our knowledge, our results demonstrated for the first time the resting FNC among pain-related ICNs. However, our results suggest that FNC signatures alone are not able to characterize the putative central dysfunction underpinning somatoform pain disorder.