Somatoform Pain Disorder Research Articles

The effect of alexithymia and depressive feelings on pain perception in somatoform pain disorder

ObjectiveTo investigate the relationship between alexithymia and depression and their influence on the subjective versus experimental pain perception in somatoform pain disorder. MethodsThree groups consisting of 40 patients with somatoform pain disorder, 40 patients with depression, and 40 healthy controls were matched. They completed questionnaires regarding alexithymia (TAS26) and depressive feelings (BDI-II). In addition, pain patients rated their subjective pain intensity (NRS). Quantitative sensory testings were conducted in all participants examining temperature (CPT, HPT) and mechanical (MPT, PPT) thresholds. ResultsAnalysis of variance showed that alexithymia was significantly increased in both patient groups compared to healthy controls, but with the highest amount in somatoform pain. Regression analyses confirmed that this finding was in part due to a high comorbidity of depressive feelings in both patient groups. We found a discrepancy between increased clinical pain ratings and elevated pressure pain thresholds, indicating a less intense mechanical pain perception in somatoform pain. Correlation analyses demonstrated a significant connection of subjective pain ratings and pressure pain thresholds with depressive feelings. ConclusionContrary to the results of other experimental pain studies on chronic muskuloskeletal pain syndromes, we could not confirm central sensitization in somatoform pain disorder. Our findings place the somatoform pain disorder more in the direction of affective disorder such as depression. These findings may improve a better understanding of the disease and also have direct therapeutic implications. The high occurrence of alexithymia and depressive feelings in somatoform pain should be considered in diagnostic and therapeutic regimens of these patients.

Using clonidine in the treatment of tizanidine abuse and withdrawal: a case report of a patient with somatoform pain disorder

ABSTRACT Tizanidine is a noradrenergic alpha-2 receptor agonist approved in the treatment of muscle spasticity. Limited data on abuse and withdrawal of Tizanidine are available. We present a case of severe withdrawal and symptoms of psychological and physiological dependence: A 52-year-old woman who was transferred to the psychosomatic unit because of pain and anxiety. She presented with a long history of inpatient treatment due to symptoms of pain. After multiple treatment options had been tried without much efficacy, the patient was prescribed Tizanidine for her symptoms of pain. As symptoms were diminished, treatment was upheld. Soon, abuse, and later, dependence of Tizanidine had established. At time of admission, the patient had been on a self-escalated daily administration scheme of 40 mg of Tizanidine. As dose tapering proved unsuccessful, dose reduction with Lorazepam to reduce withdrawal symptoms was attempted. As also the additive treatment with Lorazepam showed no satisfying results, another treatment option was needed. After establishing Clonidine, the off tapering of Tizanidine was much better tolerated by the patient and finally proved successful. This case report draws attention to possible severe abuse of Tizanidine and the major clinical aspects and challenges in the treatment of Tizanidine withdrawal.

Variations in psychiatric morbidity between traumatized Norwegian, refugees and other immigrant patients in Oslo

Background: There is a lack of clinical studies that focus on different psychiatric disorders after trauma and the relationship with migration status.Purpose: To examine differences in psychiatric morbidity in traumatized patients referred to psychiatric treatment in Southern Oslo.Materials and methods: Hundred and ten patients with trauma background attending an outpatient clinic in Southern Oslo were studied. Forty-four of the participants (40%) were ethnic Norwegians, 25 (22.7%) had refugee background and 41 (37.3%) were first- or second-generation immigrants without refugee background. Thorough diagnostic assessment was done by experienced psychiatrists through several structured clinical interviews and self-report questionnaires.Results: Ninety-eight patients (89%) were diagnosed with at least one Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (DSM-IV-TR) disorder. There was a clear difference in the presentation of certain psychiatric disorders between the groups. Ethnic Norwegian patients were more likely to have anxiety disorders: agoraphobia, social phobia and panic disorder than non-refugee immigrant patients. They also had higher rates of alcohol abuse/dependence. Somatoform pain disorder was more common in both the refugee and other-immigrant groups than among the ethnic Norwegian patients. The refugee patients had significantly more major depressive disorder, post-traumatic stress disorder (PTSD) and both co-occurring.Conclusion: Trauma is frequently associated with depression, anxiety disorders, somatoform pain disorder and PTSD in a clinical population. The clinical presentation and comorbidity of these disorders seem to vary significantly between traumatized patients with Norwegian, refugee and non-refugee immigrant backgrounds. After a major trauma, refugees may be at greater risk for both PTSD and depression than other immigrants and the native population.

Aberrant Thalamic-Centered Functional Connectivity in Patients with Persistent Somatoform Pain Disorder.

PurposeRecent task-based fMRI studies have shown that Persistent Somatoform Pain Disorder (PSPD) patients demonstrated aberrant activity in a wide range of brain regions associated with sensation, cognition and emotion. However, these specific task-based studies could not clearly uncover the alterations in the spontaneous brain networks that were associated with the general pain-related symptoms in PSPD.Patients and MethodsIn the present study, 13 PSPD patients and 23 matched healthy controls (HCs) were enrolled. Resting state and 3D structural imaging data were collected during magnetic resonance imaging (MRI) scans. Ninety regions of interest (ROIs) were selected from the automated anatomical labeling (AAL) template. The functional connectivity toolbox “CONN” was used to calculate the functional connectivity (FC) coefficients.ResultsOur results showed that PSPD patients exhibited increased FCs between the left thalamus and the right amygdala, the right hippocampus, and multiple sub-regions of the occipital lobe when compared to HCs. Correlation analysis revealed a negative correlation between the left thalamus-right amygdala FC and the level of anxiety in PSPD patients.ConclusionThese findings suggest that the altered FC between thalamus and amygdala may be the neural mechanisms underlying the pain-related anxiety in PSPD.

Functional symptoms in dermatology: Part 2.

Functional disorders within dermatology present as various constellations of skin symptoms, but without evidence of organic pathology. Examples can include mucocutaneous pain syndromes, functional pruritus, somatoform pain disorder and rarer entities, such as undifferentiated somatoform idiopathic anaphylaxis and multiple chemical sensitivity syndrome. These conditions can have a significant impact on a patient's quality of life, and can present challenges in communication, investigation and management. The aetiology of functional disorders is not fully understood, but with an effective collaborative approach, a psychological explanation for these symptoms is often found. A structured approach to assessment can lead to a confident diagnosis, and understanding a patient's belief system and the impact of symptoms on their functioning can give better grounding for successful management. Treatment is dependent on the level of the patient's engagement with healthcare professionals, and often takes a measured and rehabilitative approach. Psychological therapies have been shown to be effective, often alongside both psychopharmacological and topical medications.

Hyperexcitability of Cortical Oscillations in Patients with Somatoform Pain Disorder: A Resting-State EEG Study

Patients with somatoform pain disorder (SPD) suffer from somatic pain that cannot be fully explained by specific somatic pathology. While the pain experience requires the integration of sensory and contextual processes, the cortical oscillations have been suggested to play a crucial role in pain processing and integration. The present study is aimed at identifying the abnormalities of spontaneous cortical oscillations among patients with SPD, thus for a better understanding of the ongoing brain states in these patients. Spontaneous electroencephalography data during a resting state with eyes open were recorded from SPD patients and healthy controls, and their cortical oscillations as well as functional connectivity were compared using both electrode-level and source-level analysis. Compared with healthy controls, SPD patients exhibited greater resting-state alpha oscillations (8.5-12.5 Hz) at the parietal region, as reflected by both electrode-level spectral power density and exact low-resolution brain electromagnetic tomography (eLORETA) cortical current density. A significant correlation between parietal alpha oscillation and somatization severity was observed in SPD patients, after accounting for the influence of anxiety and depression. Functional connectivity analysis further revealed a greater frontoparietal connectivity of the resting-state alpha oscillations in SPD patients, which was indexed by the coherence between pairs of electrodes and the linear connectivity between pairs of eLORETA cortical sources. The enhanced resting-state alpha oscillation in SPD patients could be relevant with attenuated sensory information gating and excessive integration of pain-related information, while the enhanced frontoparietal connectivity could be reflecting their sustained attention to bodily sensations and hypervigilance to somatic sensations.

Role of coping with negative emotions in cognitive behavioral therapy for persistent somatoform pain disorder: Is it more important than pain catastrophizing?

Cognitive behavioral therapy (CBT) is known to be effective for patients with persistent somatoform pain disorder (PSPD). Improvement of negative emotions in interpersonal stressful situations has been reported to reduce PSPD-related clinical pain. However, these associations in CBT remain unclear. Therefore, we examined the relation between changes in negative emotions and clinical pain symptoms after CBT by using a multiple regression analysis that included pain catastrophizing. We analyzed negative emotional intensity scores in stressful situations of 38 patients with PSPD who had completed CBT treatment and all the daily worksheets. Negative emotional intensity scores were recorded in daily worksheets during 12 weekly CBT sessions. Scores for the Pain Catastrophizing Scale (PCS), Visual Analogue Scale (VAS) as clinical pain intensity, Beck Depression Inventory - Second Edition (BDI-II), and State-Trait Anxiety Inventory (STAI) were also obtained at pre- and post-treatment. A multiple regression analysis was conducted using changes in VAS scores after CBT as the dependent variable, and changes in negative emotional intensity, PCS, BDI-II, and STAI scores after CBT, age, and sex as independent variables. Negative emotional intensity scores decreased after CBT. In a multiple regression analysis, the emotional changes resulting from CBT depicted a modest positive relation with changes in VAS scores (β = 0.37; P < 0.05); however, there was no relation between changes in PCS scores after CBT and changes in VAS scores after CBT (β = 0.03). The results show that negative emotions play an important role in the treatment effects of CBT for PSPD.

Altered Brain Functional Hubs and Connectivity Underlie Persistent Somatoform Pain Disorder.

This study investigated the degree of brain functional impairment in persistent somatoform pain disorder (PSPD) by examining changes in the patterns of brain functional hubs. Resting-state functional magnetic resonance imaging was performed in 21 PSPD patients with headache as the main symptom and 17 sex- and age-matched healthy controls. Degree centrality (DC) analysis as well as the connectivity among these hubs by functional connectivity (FC) analysis and Granger causality analysis (GCA) were performed to characterize abnormal brain networks in PSPD (Gaussian random field corrected: P < 0.001, Z > 3.09). The relationships between DC and connectivity and clinical parameters were also examined. DC values in the bilateral inferior occipital gyrus (IOG), bilateral calcarine fissure (CAL), and left paracentral lobule (PCL) and FC values of right IOG–left CAL, right IOG–right CAL, right IOG–left IOG, left CAL–right CAL, left CAL–left IOG, left CAL–left PCL, right CAL–left PCL, and left IOG–left PCL were lower in PSPD patients as compared to controls. A negative causal effect from the left CAL to the left paracentral lobule and a positive effect from the right CAL to the right IOG were observed in PSPD patients. Abnormal DC, FC, and signed-path coefficients in PSPD patients were negatively correlated with self-rating anxiety and depression scale scores. These results indicate that altered functional hubs and connectivity patterns in the somatosensory cortex may reflect emotional disturbance in PSPD patients.

Reduced empathic pain processing in patients with somatoform pain disorder: Evidence from behavioral and neurophysiological measures

The present study aimed to investigate the alterations of psychophysiological responses to empathy for pain among patients with somatoform pain disorder (SPD). Behavioral and event-related potential (ERP) responses to pictures depicting hands or feet in different non-painful or painful situations were compared between 18 SPD patients and 18 healthy controls. Patients with SPD reported lower unpleasantness to the observation of others' pain than healthy controls, thus suggesting a reduced affective sharing to others' pain in SPD. While healthy controls showed significant different N2 and P3 responses between painful and non-painful stimulations, no significant difference was observed for patients with SPD. In addition, while both patients and controls showed enlarged late positive potential (LPP) response to painful stimulation than to non-painful stimulation, the differential LPP response was significantly smaller in patients than controls. These ERP results suggested a reduced response to empathy for pain in both early affective and late cognitive temporal stages in SPD. Mediation analysis further revealed that alexithymia mediated the effect of somatoform pain on empathic N2 responses, suggesting that the reduced early affective sharing process in SPD was mediated by their heightened alexithymia. To sum up, our results demonstrated the reduced psychophysiological responses to empathy for pain among patients with SPD, where the reduced affective sharing process could be explained by the concurrent alexithymia. While the altered empathy for pain exhibited by these patients with SPD could impact their social functioning, our study would provide some insights into interventions aimed at improving empathy-related social functioning.

A new coumarin from Murraya alata activates TRPV1 channel

One new coumarin, muralatin R, was isolated from the leaves of Murraya alata Drake (Rutaceae). Its structure was elucidated by extensive analysis of the NMR and MS data, along with the specific rotation comparison. Muralatin R was found to be capable of activating the transient receptor potential vanilloid 1 (TRPV1) channel through desensitization mechanism. The results supply reference for clarification of the therapeutic basis and mechanism of action of Murraya plants for treating psychogenic pain or somatoform pain disorders.

Structural alterations in functional neurological disorder and related conditions: a software and hardware problem?

Functional neurological (conversion) disorder (FND) is a condition at the interface of neurology and psychiatry. A “software” vs. “hardware” analogy describes abnormal neurobiological mechanisms occurring in the context of intact macroscopic brain structure. While useful for explanatory and treatment models, this framework may require more nuanced considerations in the context of quantitative structural neuroimaging findings in FND. Moreover, high co-occurrence of FND and somatic symptom disorders (SSD) as defined in DSM-IV (somatization disorder, somatoform pain disorder, and undifferentiated somatoform disorder; referred to as SSD for brevity in this article) raises the possibility of a partially overlapping pathophysiology. In this systematic review, we use a transdiagnostic approach to review and appraise the structural neuroimaging literature in FND and SSD. While larger sample size studies are needed for definitive characterization, this article highlights that individuals with FND and SSD may exhibit sensorimotor, prefrontal, striatal-thalamic, paralimbic, and limbic structural alterations. The structural neuroimaging literature is contextualized within the neurobiology of stress-related neuroplasticity, gender differences, psychiatric comorbidities, and the greater spectrum of functional somatic disorders. Future directions that could accelerate the characterization of the pathophysiology of FND and DSM-5 SSD are outlined, including “disease staging” discussions to contextualize subgroups with or without structural changes. Emerging neuroimaging evidence suggests that some individuals with FND and SSD may have a “software” and “hardware” problem, although if structural alterations are present the neural mechanisms of functional disorders remain distinct from lesional neurological conditions. Furthermore, it remains unclear whether structural alterations relate to predisposing vulnerabilities or consequences of the disorder.

Stressful life events and quality of life in patients with somatoform disorders

Background: Stressful life events are associated with somatoform disorders. Somatoform disorders can influence the quality of life (QOL). These factors are culture-specific and less studied in the Indian population. Objective: The objective of this study was to evaluate the stressful life events and QOL in patients with somatoform disorders. Materials and Methods: This cross-sectional observational study was done by examining the life events and QOL of 112 consecutive patients who were diagnosed with somatoform disorders. Mini Neuropsychiatric Interview Plus, Presumptive Stressful Life Events Scale (PSLES), and WHO Quality of Life-Bref scales were administered. Results: The study sample had undifferentiated somatoform disorder (32.1%), persistent somatoform pain disorder (26.7%), and somatization disorder (25.9%). The common stressful life events experienced by somatoform disorder patients were financial issues (27.7%), marital conflicts (20.5%), family conflicts (18.7%), and illness in family members (16%). Males reported predominantly financial and job-related stressors, whereas females reported stress in family and interpersonal domain. The mean stress score using PSLES among the participants was 114.9, and the score of mean life events experienced by the participants was 2.03. QOL scores in domains such as physical, psychological, social relationship, and environment were 44.3, 41.4, 46.6, and 47.7, respectively. These were low when compared to population norms. There was a significant positive correlation between the duration of the somatoform disorder and the stress scores and a negative correlation which was not significant between the duration of illness and QOL. Conclusions: There is a difference between stressors experienced between the two genders, the knowledge of which would help in tailoring individual needs in management. There is significant impairment in the QOL in people with somatoform disorder.

Long-term opioid therapy of non-cancer pain : Prevalence and predictors of hospitalization in the event of possible misuse.

One major concern of long-term opioid therapy (LTOT) for chronic noncancer pain (CNCP) is the risk of abuse of prescribed opioids. To examine the prevalence and predictors of opioid use-related hospitalizations and potential abuse of prescribed opioids by persons with LTOT for CNCP in asample representative of the German statutory health insurance companies. Retrospective cross-sectional study in 2014. Anonymized German health claims database, including 4,028,618 insured individuals of 69German statutory health insurances. Univariate logistic regression models to evaluate demographic and medical characteristics associated with hospital stays and a diagnosis of mental and behavioral disorders due to alcohol, opioids, tranquilizers, multiple substances and intoxications by narcotic agents in insured individuals with CNCP receiving LTOT. The prevalence of LTOT for CNCP was 0.8%; 9.9% of these insured individuals received high-dose LTOT (≥120 morphine equivalent mg/day). The 1‑year prevalence of hospital stays with a diagnosis of mental and behavioral disorders due to alcohol, opioids, tranquilizers, multiple substances and intoxications by narcotic agents was 1.75% of persons with LTOT. These diagnoses were strongly associated with prescriptions of tranquilizers (odds ratio [OR] 3.63; 95% confidence interval [CI] 3.03; 4.36) and moderately associated with diagnosis of depression (OR 2.52; 95% CI 2.12; 3.00) and slightly associated with diagnosis of somatoform pain disorder (OR 1.89; 95% CI 1.56; 2.28) and high-dose LTOT (OR 1.81; 95% CI 1.44; 2.27). The study is in line with the recommendations of the German national guidelines on long-term opioid therapy of chronic non-cancer pain (LONTS) to avoid concomitant prescription of tranquilizers for CNCP and to carefully select and monitor patients with depression and somatoform pain disorder.

Fronto-Insular Connectivity during Pain Distraction Is Impaired in Patients with Somatoform Pain.

Somatoform pain disorder is characterized by chronic pain and various psychological symptoms including increased attention to mental and physical processes. Given that the medial prefrontal cortex (mPFC) of the default mode network (DMN) and the anterior insula of the salience network are critically involved in intrinsic and attentional processes, we investigated the involvement of these networks during the distraction from physical pain in somatoform pain patients. During painful and nonpainful heat stimulation, attentional distraction from physical processes was modulated with a Stroop task. Thirteen patients were investigated with functional magnetic resonance imaging (fMRI) and compared to 13 controls. Main outcomes were spatial maps of coherent fMRI activity based on independent component analysis and functional connectivity (FC) resulting from psychophysiological interaction analysis. Behavioral pain intensity ratings were reduced during the distraction task in both groups. At brain level, we found deviant network activities in the DMN (particularly in the mPFC) and in the salience network (bilaterally in the anterior insula) in patients. During pain stimulation, Stroop-induced distraction decreased the FC between the mPFC and anterior insula in controls but not in patients. Modulating the FC between the mPFC and the insula may be highly relevant for shifting the attention away from external stimuli, including nociceptive input. The observed alterations in somatoform pain patients may foster new strategies in cognitive behavioral training tools for these patients.

The Effectiveness of High-frequency Repetitive Transcranial Magnetic Stimulation in Persistent Somatoform Pain Disorder: A Case Series

Somatoform pain disorders (SPD) are common, disabling and do not respond well to existing treatment modalities. We investigated the usefulness of 18 sessions of high frequency repetitive transcranial magnetic stimulation delivered at the left dorsolateral prefrontal cortex (DLPFC) in five right-handed patients with SPD. All patients reported significant improvement in pain relief and activities of daily living. High-frequency repetitive transcranial magnetic stimulation (rTMS) delivered at the left DLPFC may be useful in SPD.

Facts and myths pertaining to fibromyalgia

Fibromyalgia (FM) is characterized by chronic widespread pain, unrefreshing sleep, physical exhaustion, and cognitive difficulties. It occurs in all populations throughout the world, with prevalence between 2% and 4% in general populations. Definition, pathogenesis, diagnosis, and treatment of FM remain points of contention, with some even contesting its existence. The various classification systems according to pain medicine, psychiatry, and neurology (pain disease; persistent somatoform pain disorder; masked depression; somatic symptom disorder; small fiber neuropathy; brain disease) mostly capture only some components of this complex and heterogeneous disorder. The diagnosis can be established in most cases by a general practitioner when the symptoms meet recognized criteria and a somatic disease sufficiently explaining the symptoms is excluded. Evidence-based interdisciplinary guidelines give a strong recommendation for aerobic exercise and cognitive behavioral therapies. Drug therapy is not mandatory. Only a minority of patients experience substantial symptom relief with duloxetine, milnacipran, and pregabalin.

Relationship between theory of mind functions with attachment styles and alexithymia in Somatoform Pain Disorder

There is sparse information available in the literature regarding attachment styles and theory of mind functions with somatoform pain disorder. Thus, the aim of the present study is to investigate the relation between somatoform pain disorder and attachment styles, theory of mind functions and alexithymia. Thirty consecutive somatoform pain disorder patients and age, education level and gender ratio matched 30 controls enrolled for the study. SCID-I Structured Clinical Therapy Patient Form, Adult Attachment Scale (AAS), Toronto Alexithymia Scala (TAS-20) Reading Mind from the Eyes Turkish Form (Eyes Test) procedures were applied to the somatoform pain disorder patients that are investigated. According to results; scores of somatoform pain disorder patients with regards to AAS avoidant subscale score, Difficulty Describing Feelings subscale, Difficulty Identifying Feeling subscale, Externally-Oriented Thinking subscale, total Alexithymia Scale scores have been found significantly higher than that of controls (p

Insecure attachment style and cumulative traumatic life events in patients with somatoform pain disorder: A cross-sectional study

ObjectiveCurrent models assume somatoform pain disorder (SPD) to be the result of a complex interaction between bio- and psychosocial factors, but the etiology is still not well understood. This study aimed to investigate the distribution of attachment style and the frequency of traumatic life events, especially childhood adversities, in patients with SPD compared to healthy controls. MethodsWe compared 65 patients with SPD (confirmed by Structured Clinical Interview, SCID-I) to 65 age- and gender-matched healthy controls. The following questionnaires were employed: Relationship Scale Questionnaire (RSQ), Essen Trauma Inventory (ETI), Childhood Trauma Questionnaire (CTQ) and Patient Health Questionnaire (PHQ-15). A logistic regression analysis was used to identify the association between SPD and psychological factors. ResultsInsecure attachment was significantly more prevalent (60%) in patients with SPD compared to healthy subjects (14%; p<0.001). Overall, 70.4% of patients with SPD reported three or more traumatic events in their life, compared with healthy subjects who reported predominantly one (40%). Patients with SPD scored significantly higher in all CTQ subscales compared to the healthy controls. The factor most strongly related with SPD was the insecure attachment style (OR=11.20, 95% CI: 1.32–94.86). Other significant predictive factors were depression (OR=3.35, 95% CI: 1.84–6.11) and number of traumatic events (OR=2.04, 95% CI: 1.06–3.92). Insecure attachment, depression symptoms and the number of traumatic events explained 86.2% of the variance. ConclusionsThe high predictive value of insecure attachment style and cumulative traumatic events emphasize their importance as risk factors of SPD.

Changes in resting-state brain networks after cognitive–behavioral therapy for chronic pain

Cognitive-behavioral therapy (CBT) is thought to be useful for chronic pain, with the pathology of the latter being closely associated with cognitive-emotional components. However, there are few resting-state functional magnetic resonance imaging (R-fMRI) studies. We used the independent component analysis method to examine neural changes after CBT and to assess whether brain regions predict treatment response. We performed R-fMRI on a group of 29 chronic pain (somatoform pain disorder) patients and 30 age-matched healthy controls (T1). Patients were enrolled in a weekly 12-session group CBT (T2). We assessed selected regions of interest that exhibited differences in intrinsic connectivity network (ICN) connectivity strength between the patients and controls at T1, and compared T1 and T2. We also examined the correlations between treatment effects and rs-fMRI data. Abnormal ICN connectivity of the orbitofrontal cortex (OFC) and inferior parietal lobule within the dorsal attention network (DAN) and of the paracentral lobule within the sensorimotor network in patients with chronic pain normalized after CBT. Higher ICN connectivity strength in the OFC indicated greater improvements in pain intensity. Furthermore, ICN connectivity strength in the dorsal posterior cingulate cortex (PCC) within the DAN at T1 was negatively correlated with CBT-related clinical improvements. We conclude that the OFC is crucial for CBT-related improvement of pain intensity, and that the dorsal PCC activation at pretreatment also plays an important role in improvement of clinical symptoms via CBT.

Regional brain functions in the resting state indicative of potential differences between depression and chronic pain

Complex relationships between depression and chronic pain have been reported in previous studies. However, only a few neuroimaging studies have investigated similarities and differences in neural systems underlying them. We examined the brain functions in the resting state of 43 patients with depression, 41 patients with chronic pain (somatoform pain disorder) and 41 healthy controls, by using regional homogeneity (ReHo) and functional connectivity analysis. Depressive symptoms were assessed by using the Beck Depression Inventory-Second Edition (BDI-II). ReHo values for the dorsolateral prefrontal cortex (DLPFC) significantly decreased for chronic pain patients, and functional connectivity between the DLPFC and thalamus decreased only for these patients. These findings are indicative of distinct brain functions related to depression and chronic pain. Understanding these differences would further elucidate the pathophysiology of these conditions.