SPECT scan in somatization disorder patients: an exploratory study of eleven cases

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.

Cognitive dysfunction and neurometabolic alternations in major depressive disorder with gastrointestinal symptoms

BACKGROUND

Brain biochemical abnormalities have been associated with major depressive disorder (MDD) and cognitive impairments. However, the cognitive performance and neurometabolic alterations of MDD patients accompanied by gastrointestinal (GI) symptoms remain to be elucidated. We aimed to reveal the features and correlation between cognitive impairments and brain biochemical abnormalities of depressed patients with GI symptoms.

METHODS

Fifty MDD patients with GI symptoms (GI group), 46 patients without GI symptoms (NGI group) and 50 demographically matched healthy controls (HCs) underwent Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) assessments. In addition, proton magnetic resonance spectroscopy (¹H-MRS) was used to obtain ratios of N-acetyl aspartate to creatine (NAA/Cr) and choline-containing compounds to creatine (Cho/Cr) in the thalamus, putamen and anterior cingulate cortex (ACC). Finally, association analysis was conducted to investigate the relationships of these measurements.

RESULTS

Compared to HCs, participants in both the GI and NGI groups had significantly reduced performance in the six MCCB cognitive domains (all p < 0.05), except for reasoning and problem solving. Higher Cho/Cr ratios in the right thalamus (p < 0.05) and lower NAA/Cr ratios in the left putamen (p < 0.05) were found in the NGI group than in the GI group. The severity of GI symptoms was negatively correlated with Cho/Cr ratios in the right ACC (r = -0.288, p = 0.037). In addition, the T-scores of visual learning were negatively correlated with NAA/Cr ratios in the right ACC (r = -0.443, p = 0.001) and right thalamus (r = -0.335, p = 0.015).

CONCLUSION

Our findings suggest that MDD patients with GI symptoms may exhibit greater neurometabolic alternations than those without GI symptoms, while both show similar cognitive dysfunction. In addition, neurometabolic alterations in the ACC and thalamus may underlie the neural basis of GI symptoms and cognitive impairment in MDD.

Frequency-specific alterations of the frontal-cerebellar circuit in first-episode, drug-naive somatization disorder

BACKGROUND

With the development of imaging techniques, evidence of abnormal neural activity has been implicated in patients with somatization disorder (SD). It remains unclear whether abnormal spontaneous neural activities are related to specific frequency bands. In this study, resting-state functional magnetic resonance imaging (fMRI) using the frequency-specific amplitude of low frequency fluctuation (ALFF) approach was applied to investigate changes in spontaneous neural activity in different frequency bands in patients with SD.

METHODS

Twenty-five first-episode, medication-naive patients with SD and 28 age-, sex-, education-matched healthy controls (HCs) underwent resting-state fMRI. The ALFF method with the classical low-frequency (0.01 - 0.08 Hz), slow-5 (0.01 - 0.027 Hz) and slow-4 (0.027 - 0.08 Hz) bands was employed to analyze the data.

RESULTS

With the classical low-frequency and slow-5 bands, patients with SD showed significantly increased ALFF in the left orbitofrontal cortex (OFC) and reduced ALFF in the right cerebellum compared with HCs. With the slow-4 band, patients with SD exhibited significantly reduced ALFF in the right cerebellum compared with HCs. However, no significant correlation was observed between the ALFF value in the left OFC or right cerebellum and clinical/cognitive variables.

CONCLUSIONS

Our findings indicate that there are abnormal regional activities of the left OFC and right cerebellum in first-episode, treatment-naive patients with SD, suggesting that these alterations occur early in the course of the disease and are independent of medication status. Our study provides novel evidence that different regional activities of the frontal-cerebellar circuit may be involved in the pathophysiology of SD.

Briquet syndrome revisited: implications for functional neurological disorder

With the creation of the Somatic Symptom and Related Disorders category of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition in 2013, the functional neurological (symptom) disorder diagnostic criteria underwent transformative changes. These included an emphasis on ‘rule-in’ physical examination signs/semiological features guiding diagnosis and the removal of a required proximal psychological stressor to be linked to symptoms. In addition, the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition somatization disorder, somatoform pain disorder and undifferentiated somatoform disorder conditions were eliminated and collapsed into the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition somatic symptom disorder diagnosis. With somatic symptom disorder, emphasis was placed on a cognitive-behavioural (psychological) formulation as the basis for diagnosis in individuals reporting distressing bodily symptoms such as pain and/or fatigue; the need for bodily symptoms to be ‘medically unexplained’ was removed, and the overall utility of this diagnostic criteria remains debated. A consequence of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition restructuring is that the diagnosis of somatization disorder that encompassed individuals with functional neurological (sensorimotor) symptoms and prominent other bodily symptoms, including pain, was eliminated. This change negatively impacts clinical and research efforts because many patients with functional neurological disorder experience pain, supporting that the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition would benefit from an integrated diagnosis at this intersection. We seek to revisit this with modifications, particularly since pain (and a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition somatization disorder comorbidity, more specifically) is associated with poor clinical prognosis in functional neurological disorder. As a first step, we systematically reviewed the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition somatization disorder literature to detail epidemiologic, healthcare utilization, demographic, diagnostic, medical and psychiatric comorbidity, psychosocial, neurobiological and treatment data. Thereafter, we propose a preliminary revision to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition allowing for the specifier functional neurological disorder ‘with prominent pain’. To meet this criterion, core functional neurological symptoms (e.g. limb weakness, gait difficulties, seizures, non-dermatomal sensory loss and/or blindness) would have ‘rule-in’ signs and pain (>6 months) impairing social and/or occupational functioning would also be present. Two optional secondary specifiers assist in characterizing individuals with cognitive-behavioural (psychological) features recognized to amplify or perpetuate pain and documenting if there is a pain-related comorbidity. The specifier of ‘with prominent pain’ is etiologically neutral, while secondary specifiers provide additional clarification. We advocate for a similar approach to contextualize fatigue and mixed somatic symptoms in functional neurological disorder. While this preliminary proposal requires prospective data and additional discussion, these revisions offer the potential benefit to readily identify important functional neurological disorder subgroups—resulting in diagnostic, treatment and pathophysiology implications.

Functional Neurological Symptom Disorder: A Diagnostic Algorithm

Functional neurological symptom disorder (FNSD) is a neuropsychiatric disorder characterized by the presence of neurological symptoms in the absence of any neurological abnormality that can be linked to a known pathology. Few studies have taken interest in this subject probably because of the heterogeneity of results. It is most often a diagnosis of exclusion which often means that patients undergo many tests and find themselves erring for a diagnosis with very little satisfaction of the outcomes. A reliable imagery pattern would therefore provide some relief and confirmation for both patients and clinicians. It could also facilitate acceptation of the diagnosis and reduce the societal cost associated with FNSD for the patient. The aim of this present study was to describe a clinicoradiological correspondence algorithm of FNSD using the PET scan and SPECT scan (PoSPs) and grant the clinician with a reliable tool to facilitate the diagnosis of FNSD. A systematic review according to the 2009 PRISMA criteria statement was used to guide the review. Our study included 3 of our own consenting patients who met the Diagnostic and Statistical Manual of Mental Disorders 5^th edition criteria as well as 25 other patients from 7 different studies. Our results showed a hypoactivation with poor clinicoradiological correspondence and poor stability in time. This hypoactivation was mostly in the frontal lobe, which could explain some behavioral alterations. These findings oppose the ones found in organic pathologies and therefore should orient towards FNSD. In the light of these findings, we recommend the clinicians to perform two PoSPs, searching for clinicoradiological lack of correspondence and time stability using our algorithm.

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.

Changes in metabolites in the brain of patients with fibromyalgia after treatment with an NMDA receptor antagonist

The aims of this work were to evaluate whether the treatment of patients with fibromyalgia with memantine is associated with significant changes in metabolite concentrations in the brain, and to explore any changes in clinical outcome measures. Magnetic resonance spectroscopy was performed of the right anterior and posterior insula, both hippocampi and the posterior cingulate cortex. Questionnaires on pain, anxiety, depression, global function, quality of life and cognitive impairment were used. Ten patients were studied at baseline and after three months of treatment with memantine. Significant increases were observed in the following areas: N-acetylaspartate (4.47 at baseline vs. 4.71 at three months, p = 0.02) and N-acetylaspartate+N-acetylaspartate glutamate in the left hippocampus (5.89 vs. 5.98; p = 0.007); N-acetylaspartate+N-acetylaspartate glutamate in the right hippocampus (5.31 vs 5.79; p = 0.01) and the anterior insula (7.56 vs. 7.70; p = 0.033); glutamate+glutamine/creatine ratio in the anterior insula (2.03 vs. 2.17; p = 0.022) and the posterior insula (1.77 vs. 2.00; p = 0.004); choline/creatine ratio in the posterior cingulate (0.18 vs. 0.19; p = 0.023); and creatine in the right hippocampus (3.60 vs. 3.85; p = 0.007). At the three-month follow-up, memantine improved cognitive function assessed by the Cognition Mini-Exam (31.50, SD = 2.95 vs. 34.40, SD = 0.6; p = 0.005), depression measured by the Hamilton Depression Scale (7.70, SD = 0.81 vs. 7.56, SD = 0.68; p = 0.042) and severity of illness measured by the Clinical Global Impression severity scale (5.79, SD = 0.96 vs. 5.31, SD = 1.12; p = 0.007). Depression, clinical global impression and cognitive function showed improvement with memantine. Magnetic resonance spectroscopy could be useful in monitoring response to the pharmacological treatment of fibromyalgia.

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.

Features of Resting-State Electroencephalogram Theta Coherence in Somatic Symptom Disorder Compared With Major Depressive Disorder: A Pilot Study

OBJECTIVE

Somatic symptom disorder (SSD) often co-occurs with major depressive disorder (MDD). Both conditions share common psychobiological and biobehavioral characteristics, but little is known about differential patterns in brain function. In this study, we compared resting-state functional brain connectivity between SSD and MDD using quantitative electroencephalography.

METHODS

Fifteen patients with SSD (SSD group), 15 patients with MDD (MDD group), and 15 healthy volunteers (healthy control [HC] group) participated in this study. Participants were assessed with quantitative electroencephalography using a 21-channel electroencephalogram system. Electroencephalogram coherence in the theta frequency range (3.5-7.5 Hz) was assessed between the following seven electrode pairs: Fp1 and Fp2, F7 and T3, F8 and T4, T5 and P3, P4 and T6, P3 and Pz, and Pz and P4. Differences in coherence between groups were analyzed using analysis of variance.

RESULTS

Theta coherence between the F7 and T3 electrodes was lower in the SSD group than the MDD and HC groups (F(2,42) = 6.67, p = .0030). Theta coherence between the T5 and P3 electrodes was lower in the SSD and MDD groups than the HC group (F(2,42) = 5.65, p = .0067). Theta coherence between the Pz and P4 electrodes was lower in the SSD group than the MDD group (F(2,42) = 6.41, p = .0037).

CONCLUSIONS

Both SSD and MDD patients commonly showed decreased functional connectivity within the left temporoparietal junction, which has neurophysiological implications for cognitive-attentional processing and social interaction. Frontostriatal circuit dysfunction affects processes that control perception and emotion, as well as misperception of somatosensory data in the parietal somatosensory area, and is more likely to be a neuropathology of SSD than MDD.

All in the mind? The neural correlates of unexplained physical symptoms

Physical symptoms with no medical explanation are commonly experienced by healthy people and those attending clinics. Psychiatrists see such patients in liaison settings and clinics for those with psychotic and affective disorders. The pathophysiology remains obscure; physical investigations are usually performed to exclude pathology rather than elucidate dysfunction. However, modern neuroimaging has allowed the study of nervous system structure and function. Although there are few diagnostically specific findings, patterns of association have emerged: where action is impeded (certain forms of conversion disorder and chronic fatigue syndrome) frontal systems of the brain are often implicated; when subjective awareness of the body is disturbed (passivity phenomena and anorexia nervosa) temporo-parietal cortices appear to be dysfunctional. The caudate nuclei (components of the frontal executive circuit) are implicated in a variety of syndromes (including body dysmorphic disorder, somatisation and chronic fatigue). The brain may be viewed as a cognitive neurobiological entity, crucially oriented towards action (for survival). Psychiatric syndromes that have an impact on bodily awareness signal dysfunction within systems representing that body and its performance in time and space.

Bidirectional Causal Connectivity in the Cortico-Limbic-Cerebellar Circuit Related to Structural Alterations in First-Episode, Drug-Naive Somatization Disorder

Background: Anatomical and functional deficits in the cortico-limbic-cerebellar circuit are involved in the neurobiology of somatization disorder (SD). The present study was performed to examine causal connectivity of the cortico-limbic-cerebellar circuit related to structural deficits in first-episode, drug-naive patients with SD at rest. Methods: A total of 25 first-episode, drug-naive patients with SD and 28 healthy controls underwent structural and resting-state functional magnetic resonance imaging. Voxel-based morphometry and Granger causality analysis (GCA) were used to analyze the data. Results: Results showed that patients with SD exhibited decreased gray matter volume (GMV) in the right cerebellum Crus I, and increased GMV in the left anterior cingulate cortex (ACC), right middle frontal gyrus (MFG), and left angular gyrus. Causal connectivity of the cortico-limbic-cerebellar circuit was partly affected by structural alterations in the patients. Patients with SD showed bidirectional cortico-limbic connectivity abnormalities and bidirectional cortico-cerebellar and limbic-cerebellar connectivity abnormalities. The mean GMV of the right MFG was negatively correlated with the scores of the somatization subscale of the symptom checklist-90 and persistent error response of the Wisconsin Card Sorting Test (WCST) in the patients. A negative correlation was observed between increased driving connectivity from the right MFG to the right fusiform gyrus/cerebellum IV, V and the scores of the Eysenck Personality Questionnaire extraversion subscale. The mean GMV of the left ACC was negatively correlated with the WCST number of errors and persistent error response. Negative correlation was found between the causal effect from the left ACC to the right middle temporal gyrus and the scores of WCST number of categories achieved. Conclusions: Our findings show the partial effects of structural alterations on the cortico-limbic-cerebellar circuit in first-episode, drug-naive patients with SD. Correlations are observed between anatomical alterations or causal effects and clinical variables in patients with SD, and bear clinical significance. The present study emphasizes the importance of the cortico-limbic-cerebellar circuit in the neurobiology of SD.

Anatomical distance affects cortical-subcortical connectivity in first-episode, drug-naive somatization disorder

BACKGROUND

Brain structural and functional alterations in the cortical-subcortical circuits have been observed in somatization disorder (SD). However, whether and how anatomical distance affects the cortical-subcortical connectivity in SD remain unclear. This study aims to examine whether anatomical distance affects the cortical-subcortical in first-episode, drug-naive SD.

METHODS

Twenty-five first-episode, drug-naive patients with SD and twenty-eight healthy controls were recruited for a resting-state scan. Regional functional connectivity strength (FCS) was calculated for each voxel in the brain, which was further divided into short- and long-range FCSs. Correlation analyses were conducted between abnormal FCS and clinical/cognitive variables in the patients.

RESULTS

Compared with the controls, the patients showed increased short-range positive FCS (spFCS) in the right superior frontal gyrus (SFG) and decreased spFCS in the left pallidum, and increased long-range positive FCS (lpFCS) in the left middle frontal gyrus and right inferior temporal gyrus (ITG). Positive correlations were observed between the spFCS values in the right SFG and Eysenck Personality Questionnaire psychoticism scores (r=0.441, p=0.027, uncorrected) and between the lpFCS values in the right ITG and scores of digit symbol-coding of Wechsler Adult Intelligence Scale (r=0.416, p=0.039, uncorrected) in the patients CONCLUSIONS: The patients exhibited increased spFCS/lpFCS in the cortical regions and decreased spFCS in the subcortical regions. The left pallidum is first reported here to show decreased spFCS in SD. The present results suggest that abnormal cortical-subcortical circuits may play an important role in SD neurobiology.

Effects of subclinical depression, anxiety and somatization on brain structure in healthy subjects

BACKGROUND

Dimensional approaches in highly prevalent psychiatric disorders like depression or anxiety could lead to a better understanding of pathogenesis and advantages in early detection and prevention. In an effort to better understand associations of brain structural variation across the depression/anxiety spectra, we investigated minor subclinical symptoms in a non-clinical healthy population.

METHODS

We studied 177 healthy subjects from the community, who underwent high-resolution T1-weighted 3T MRI and completed the symptom-checklist-90 (SCL-90-R). Using voxel-based morphometry (VBM) analysis with CAT12 software, we correlated SCL-90-R-subscales for depression, anxiety, and somatization with gray matter across the brain.

RESULTS

Significant positive gray matter correlations emerged across all three scales in different areas: the depression subscale correlated positively with gray matter in the Rolandic operculum, superior temporal gyrus (left) and postcentral gyrus (bilateral), the anxiety subscale correlated positively with middle temporal gyrus, Rolandic operculum, middle cingular gyrus and precuneus bilaterally, and the somatization subscale with left inferior prefrontal cortex. Somatization also showed negative correlations with cerebellar vermis and right supplementary motor area.

LIMITATIONS

Our study is limited to VBM and does not include surface-based measures. It also only contains subjects with very small psychological distress by partly overlapping symptoms.

CONCLUSION

Our findings are consistent with a non-linear relationship between symptom severity and cortical volume in several brain areas involved in both emotion regulation as well as altered in clinically manifest depressive/anxiety disorders.

Neural correlates of conversion disorder: overview and meta-analysis of neuroimaging studies on motor conversion disorder

BACKGROUND

Conversion Disorders (CD) are prevalent functional disorders. Although the pathogenesis is still not completely understood, an interaction of genetic, neurobiological, and psychosocial factors is quite likely. The aim of this study is to provide a systematic overview on imaging studies on CDs and investigate neuronal areas involved in Motor Conversion Disorders (MCD).

METHODS

A systematic literature search was conducted on CD. Subsequently a meta-analysis of functional neuroimaging studies on MCD was implemented using an Activation Likelihood Estimation (ALE). We calculated differences between patients and healthy controls as well as between affected versus unaffected sides in addition to an overall analysis in order to identify neuronal areas related to MCD.

RESULTS

Patients with MCD differ from healthy controls in the amygdala, superior temporal lobe, retrosplenial area, primary motor cortex, insula, red nucleus, thalamus, anterior as well as dorsolateral prefrontal and frontal cortex. When comparing affected versus unaffected sides, temporal cortex, dorsal anterior cingulate cortex, supramarginal gyrus, dorsal temporal lobe, anterior insula, primary somatosensory cortex, superior frontal gyrus and anterior prefrontal as well as frontal cortex show significant differences.

CONCLUSIONS

Neuronal areas seem to be involved in the pathogenesis, maintenance or as a result of MCD. Areas that are important for motor-planning, motor-selection or autonomic response seem to be especially relevant. Our results support the emotional unawareness theory but also underline the need of more support by conduction imaging studies on both CD and MCD.

Abnormal default-mode network homogeneity and its correlations with personality in drug-naive somatization disorder at rest

BACKGROUND

While the default-mode network (DMN) appears to play a crucial role in patients suffering from somatization disorder (SD), the abnormalities of the network homogeneity (NH) of the DMN in SD patients have been poorly explored. The aim of this study is to examine DMN NH using an NH approach in patients suffering from SD at rest and determine its correlations with personality as measured by the Eysenck Personality Questionnaire (EPQ).

METHODS

A total of 25 drug-naive patients with SD and 28 sex-, age-, and education-matched healthy controls underwent functional magnetic resonance imaging scans at rest. The data were analyzed by an automated NH method.

RESULTS

Patients showed increased NH in the left superior frontal gyrus and decreased NH in the bilateral precuneus. Moreover, a significantly negative correlation was observed between the NH values in the bilateral precuneus and the EPQ--Neuroticism scores.

LIMITATIONS

The present study should be considered preliminary due to a lenient, uncorrected threshold of p<0.01.

CONCLUSIONS

The results suggest that abnormal DMN NH exists in drug-naive SD and further highlight the importance of the DMN in the pathophysiology of SD.

Decreased interhemispheric functional connectivity in insula and angular gyrus/supramarginal gyrus: Significant findings in first-episode, drug-naive somatization disorder

Neuroimaging data have demonstrated brain functional alterations in patients with somatization disorder (SD). However, there is little information on interhemispheric resting-state functional connectivity (FC) in SD. In this study, resting-state functional magnetic resonance imaging (fMRI) and voxel-mirrored homotopic connectivity (VMHC) were applied to examine the changes of interhemispheric FC of the whole brain in patients with SD. A total of 25 first-episode, medication-naive SD patients and 28 age-, sex-, education-matched healthy controls (HC) underwent resting-state fMRI, and the data were analyzed by VMHC. Compared with HC, patients had lower VMHC in the angular gyrus/supramarginal gyrus (AG/SG) and insula. The reproducibility of the results was validated using the split-half and leave-one-out validations. No significant correlation was found between the VMHC in AG/SG or insula and clinical variables. Our findings indicate that the interhemispheric FC in the AG/SG and insula is decreased in first-episode, treatment-naive patients with SD, and thus provide new insight for disruption of interhemispheric FC in the pathophysiological mechanism of SD.

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.

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.

Changes in metabolites after treatment with memantine in fibromyalgia. A double-blind randomized controlled trial with magnetic resonance spectroscopy with a 6-month follow-up

AIM

To evaluate the efficacy of memantine on metabolite levels in different areas of the brain and to determine whether changes in metabolite levels correlate with clinical variables in Fibromyalgia (FM) patients.

METHODS

Doubled-blind parallel randomized controlled trial. Twenty-five patients diagnosed with FM were enrolled in the study. Patients were administered questionnaires on pain, anxiety, depression, quality of life, and cognitive impairment, and single-voxel MRS of the brain was performed. All assessments were performed at baseline and after 6 months of treatment with memantine or placebo.

RESULTS

Patients treated with memantine exhibited a significant increase in the glutamate (P = 0.010), glutamate/creatine ratio (P = 0.013), combined glutamate + glutamine (P = 0.016) and total N-acetyl-aspartate (NAA+NAAG) (P = 0.034) in the posterior cingulate cortex compared with those on placebo. Furthermore, the memantine group exhibited increases in creatine (P = 0.013) and choline (Cho) (P = 0.025) in the right posterior insula and also a correlation between choline and the Fibromyalgia Impact Questionnaire (FIQ) in the posterior insula (P = 0.050) was observed.

CONCLUSION

Memantine treatment resulted in an increase in cerebral metabolism in FM patients, suggesting its utility for the treatment of the illness.

Evaluation of the efficacy of memantine in the treatment of fibromyalgia: study protocol for a doubled-blind randomized controlled trial with six-month follow-up

Background

Fibromyalgia is a prevalent chronic rheumatic disease of great clinical importance. Recent studies have found raised levels of glutamate in the insula, hippocampus and posterior cingulate cortex regions of the brains of fibromyalgia (FM) patients. This finding has led researchers to speculate about the usefulness of glutamate-blocking drugs such as memantine in the treatment of fibromyalgia. The hypothesis of this study is that the administration of memantine will reduce the glutamate levels, and futhermore, will decrease the perceived pain. The aim of this study is to evaluate the efficacy of memantine in the treatment of pain (pain perception). A secondary objective is to evaluate the efficacy of memantine in the treatment of other clinical symptoms of FM, and to evaluate the efficacy of memantine in reducing brain levels of glutamate, and its effects on the central nervous system as a whole.

Method/Design

A double-blind parallel randomized controlled trial. Participants, Seventy patients diagnosed with FM will be recruited from primary health care centers in Zaragoza, Spain. Intervention. The subjects will be randomized in two groups: A) A treatment group (n = 35), which will receive 20 mg of memantine daily; B) A control group (n = 35), to which will be administered a placebo. There will be a six-month follow-up period (including a titration period of one month). Outcomes. The main efficacy variable of this study is pain (pain perception). The secondary efficacy variables are clinical symptoms (pain threshold, cognitive function, health status, anxiety, depression, clinical impression and quality of life) and glutamate levels in different regions of the brain, which will be assessed by magnetic resonance spectroscopy. Randomization and blinding. Randomization has been computer-generated, and the random allocation sequence will be implemented by telephone. Subjects of the study and the research assistants will be blinded to group assignment.

Discussion

There is a need for the development of innovative and more effective treatments for fibromyalgia. This clinical trial will determine whether memantine can be an effective pharmacological treatment for fibromyalgia patients.

Trial registration

Current Controlled Trials http://ISRCTN45127327 EUDRACT 2011-006244-73

Brain dysfunction in fibromyalgia and somatization disorder using proton magnetic resonance spectroscopy: a controlled study

OBJECTIVE

To evaluate the brain metabolite patterns in patients with fibromyalgia (FM) and somatization disorder (STD) compared with healthy controls through spectroscopy techniques and correlate these patterns with psychological variables.

METHOD

Design. Controlled, cross-sectional study. Sample. Patients were recruited from primary care in Zaragoza, Spain. The control group was recruited from hospital staff. Patients were administered questionnaires on pain catastrophizing, anxiety, depression, pain, quality of life, and cognitive impairment. All patients underwent Magnetic Resonance Imaging and magnetic resonance spectroscopy (MRS).

RESULTS

A significant increase was found in the glutamate + glutamine (Glx) levels in the posterior cingulate cortex (PCC): 10.73 (SD: 0.49) for FM and 9.67 (SD: 1.10) for STD 9.54 (SD: 1.46) compared with controls (P = 0.043). In the FM + STD group, a correlation between Glx and pain catastrophizing in PCC (r = 0.397; P = 0.033) and between quality of life and the myo-inositol/creatine ratio in the left hippocampus (r = -0.500; P = 0.025) was found. To conclude Glutamate seems to be relevant in the molecular processes involved in FM and STD. It also opens the door for Proton MRS ((1) H-MRS) in STD and suggests that reducing glutamatergic activity through pharmacological treatment could improve the outcome of patients with FM and STD.

CONCLUSION

Glutamate seems to be relevant in the molecular processes involved in FM and STD. It also opens the door for Proton MRS ((1) H-MRS) in STD and suggests that reducing glutamatergic activity through pharmacological treatment could improve the outcome of patients with FM and STD.

Polysymptomatic, polysyndromic presentation of patients with urological chronic pelvic pain syndrome

PURPOSE

Somatization disorder has been described in several comorbid functional syndromes of urological chronic pelvic pain syndrome, such as irritable bowel syndrome. We investigated whether a subset of patients with urological chronic pelvic pain syndrome may have the polysymptomatic, polysyndromic presentation pattern that is common in somatization disorder.

MATERIALS AND METHODS

A total of 70 male and female patients with urological chronic pelvic pain syndrome and 35 age matched controls without the syndrome completed a 59-item symptom checklist to assess the classic polysymptomatic, polysyndromic symptom pattern. The 2 operational tools used were the Perley-Guze derived symptom checklist and the somatic symptom algorithm used for Diagnostic and Statistical Manual, 4th Edition, Text Revision somatization disorder criteria.

RESULTS

Female patients with urological chronic pelvic pain syndrome (interstitial cystitis/bladder pain syndrome) reported significantly more nonpain symptoms and pain symptoms outside the pelvis than control female urology patients (p=0.0016 and 0.0018, respectively). Female patients with urological chronic pelvic pain syndrome were more likely to endorse a polysymptomatic, polysyndromic symptom pattern than female controls (27% vs 0%, p=0.0071). In contrast, male patients with urological chronic pelvic pain syndrome (interstitial cystitis/bladder pain syndrome and/or chronic prostatitis/chronic pelvic pain syndrome) did not report more extrapelvic pain than male controls (p=0.89). Male patients with urological chronic pelvic pain syndrome were not more likely than male controls to have a polysymptomatic, polysyndromic symptom pattern.

CONCLUSIONS

A subset of female patients with urological chronic pelvic pain syndrome endorses numerous extrapelvic symptoms across multiple organ systems. The checklist may be valuable to assess patients for this polysymptomatic, polysyndromic symptom pattern, which is common in somatization disorder. Recognizing this polysymptomatic, polysyndromic presentation will prompt clinicians to investigate further to determine whether somatization disorder may be an underlying diagnosis in a small subset of patients with urological chronic pelvic pain syndrome who complain of numerous extrapelvic symptoms.

Cortical mechanisms of the symptomatology in major depressive disorder: a resting EEG study

BACKGROUND

Diagnosis and treatment rely on symptom criteria in modern psychiatry. However, the cortical mechanisms of symptomatology in major depressive disorder (MDD) are still not clear. This study examined neural correlates of symptom clusters of MDD by electroencephalography (EEG).

METHODS

Resting state eye-closed EEG signals were recorded in 196 depressive patients. Quantitative EEG (qEEG) of regional power, coherence and power series correlation across delta, theta, alpha and beta frequencies were used to correlate with overall depression severity evaluated by the Hamilton Depression Rating Scale (HDRS). Further, statistical comparisons between patients with high vs. low qEEG indices (median-split) were undertaken regarding symptom severity of core depression, sleep, activity, psychic anxiety, somatic anxiety, and delusion.

RESULTS

None of the qEEG indices significantly correlated with overall depression severity or differentiated symptom severity of core depression, sleep, activity and psychic anxiety. A higher symptom severity of somatic anxiety was associated with higher regional power over widespread cortical regions and lower strengths at bi-temporal, temporo-parietal and fronto-parietal connections. A higher symptom severity of delusion was associated with higher regional power in the frontal and temporal regions, and lower strengths at inter-hemispheric (frontal, temporal and parietal) and fronto-temporo-parietal connections.

LIMITATIONS

Our EEG recording with sampling rate of 128Hz and 20 electrodes may provide restricted spatial and temporal precision.

CONCLUSIONS

Our results suggest that cortical mechanisms play important roles in the symptom manifestation of cognitive distortion (sub-score of delusion) and somatic anxiety in MDD. Our findings further imply that psychic anxiety and somatic anxiety are distinct entities.

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

OBJECTIVE

Debate about the nature of somatoform disorders and their current diagnostic classification has been stimulated by the anticipation of new editions of Diagnostic and Statistical Manual of Mental Disorders and International Statistical Classification of Diseases and Related Health Problems diagnostic classifications. In the current paper, we review systematically the literature on the neuroimaging of somatoform disorders and related conditions with the aim of addressing two specific questions: Is there evidence of altered neural function or structure that is specifically associated with somatoform disorders? What conclusions can we draw from these findings about the etiology of somatoform disorders?

METHODS

Studies reporting neuroimaging findings in patients with a somatoform disorder or a functional somatic syndrome (such as fibromyalgia) were found using Pubmed, PsycINFO, and EMBASE database searches. Reported structural and functional neuroimaging findings were then extracted to form a narrative review.

RESULTS

A relatively mature literature on symptoms of pain and less developed literatures on conversion and fatigue symptoms were identified. The available evidence indicates that, when compared with nonclinical groups, somatoform diagnoses are associated with increased activity of limbic regions in response to painful stimuli and a generalized decrease in gray matter density; however, methodological considerations restrict the interpretation of these findings.

CONCLUSIONS

Whereas the neuroimaging literature has provided evidence about the possible mechanisms underlying somatoform disorders, this is not yet sufficient to provide a basis for classification. By adopting a wider variety of experimental designs and a more dynamic approach to diagnosis, there is every reason to be hopeful that neuroimaging data will play a significant role in future taxonomies.

A general neuropsychological model of delusion

INTRODUCTION

Neurocognitive accounts of delusion have traditionally highlighted perceptual misrepresentation, as the primary trigger in addition to other cognitive deficits that maintain the delusion. Here, a general neurocognitive model of delusional disorder (DSM-IV) is proposed, not so much based on perceptual or cognitive deficits after right hemisphere damage as on cognitive propensities, specifically excessive inferencing (especially jumping to conclusions) and excessive reference to the self, due to left hemisphere overactivity.

METHOD

The functional imaging, topographic EEG, and experimental imaging literatures on delusional disorder are reviewed, and 37 previously published cases of postunilateral lesion delusion (DSM-IV type, grandeur, persecution, jealousy, erotomania, or somatic), are reviewed and analysed multivariately.

RESULTS

Functional imaging and EEG topography data were slightly more indicative of left hemisphere overactivity in delusional disorder. In addition, 73% of the postunilateral lesion cases (χ(2)=7.8, p=.005) of delusional disorder (DSM-IV type) had a right hemisphere lesion, whereas only 27% had a left hemisphere lesion.

CONCLUSION

Left hemisphere release appears to be a more primary cause of delusional disorder than right hemisphere impairment, the latter merely entailing loss of inhibition of delusional beliefs. We propose that most patients with DSM-IV diagnoses of delusional disorder could be afflicted by excessive left hemisphere activity, but further research is necessary.

Neurocognitive functioning in women presenting with undifferentiated somatoform disorders in Oman

AIM

There is a dearth of research from non-Western populations focusing on neurocognitive functioning in patients presenting with undifferentiated somatoform disorders. The aim of the present quest is to examine the presence of cognitive impairment and other health-related parameters among attendees at psychiatric settings in Oman, an Arab/Islamic country, with a diagnosis of undifferentiated somatoform disorder.

METHOD

In order to compare the performance of patients diagnosed with undifferentiated somatoform disorder (n = 20) and normal healthy subjects (n = 18) on indices of attention and concentration, tests of executive functioning, mood, somatization and vegetative functioning were carried out.

RESULTS

The performance of patients with undifferentiated somatoform disorder differed from that of normal healthy subjects on the presently operationalized indices of working memory and executive functioning, anxiety, quality of sleep and psychosomatically expressed psychological distress.

CONCLUSION

To our knowledge, this is the first study highlighting neurocognitive functioning in patients with undifferentiated somatoform disorders from a non-Western population. This type of study has the potential of shedding light on the covariates of such a debilitating and intransigent condition as undifferentiated somatoform disorder.

Brain dysfunction behind functional symptoms: neuroimaging and somatoform, conversive, and dissociative disorders

PURPOSE OF REVIEW

Neuroimaging research in psychiatry has been increasing exponentially in recent years, yet many psychiatrists are relatively unfamiliar with this field. This article summarizes the findings of the most relevant research articles on the neuroimaging of somatoform, conversive, and dissociative disorders published from January 2007 through June 2008.

RECENT FINDINGS

Neuroimaging findings summarized here include alterations of stress regulation and coping in somatoform pain disorders, the importance of catastrophizing in somatization disorder, and the relevance of a history of physical/sexual abuse in irritable bowel syndrome. Regarding fibromyalgia, three of the most significant advances have been the impossibility of differentiating primary and concomitant fibromyalgia in the presence of quiescent underlying disease, the role of hippocampal dysfunction, and the possibility that fibromyalgia may be characterized as an aging process. In dissociative disorders, the high levels of elaborative memory encoding and the reduced size of the parietal lobe are highlighted.

SUMMARY

The most promising clinical consequence of these studies, in addition to improving knowledge about the etiology of these illnesses, is the possibility of using neuroimaging findings to identify subgroups of patients, which could allow treatments to be tailored.

Dysfunctional cognitions in idiopathic environmental intolerances (IEI)—An integrative psychiatric perspective

Idiopathic environmental intolerances (IEI) - formerly multiple chemical sensitivities (MCS) - are characterized by diffuse symptoms reported after exposure to low doses of everyday chemicals. Previous theories about the origin of IEI have emphasized either biological or psychological factors, neglecting a probable interplay. Many have suggested classifying IEI as a somatoform or an anxiety disorder, irrespective of some incongruities. By focusing on dysfunctional cognitions we discuss obvious parallels of IEI with somatoform disorders, and also indicate overlaps with anxiety and delusional disorders. To propose a hypothetical psycho-neurobiological basis of IEI, recent evidence about cortically represented symptoms in the absence of peripheral stimuli is briefly summarized. We conclude that IEI can serve as an illustrative example for the impact of cognitive, representational processes in symptom generation.

Brain glucose metabolism and temperament in relation to severe somatization

Little is known about the pathophysiology of somatization. The authors' aim was to explore associated factors with somatoform disorders. The authors studied 10 female patients with a diagnosis of somatization disorder or undifferentiated somatoform disorder with no comorbid current Diagnostic and Statistical Manual of Mental Disorders (4th edn) Axis I disorder and 12 healthy female volunteers. The predicting variables were temperament factors of the 240-item Temperament and Character Inventory instrument and regional brain glucose metabolism. Low novelty-seeking and high harm avoidance temperament traits and low caudate and low putamen glucose metabolism were statistically significantly associated with severe somatization (P < 0.05). In the present study, severe somatization associates with both altered brain glucose metabolism and temperament factors. No other studies on association of somatization with brain glucose metabolism and temperament have been published. The results are still considered exploratory due to the small number of subjects.