Antiferromagnetic Interactions through the Thirteen Å Metal-Metal Distances in Heterometallic One-Dimensional Chains.

A heterometallic and paramagnetic one-dimensional aligned chain in -Rh(+2)-Rh(+2)- Pt(+2)-Ni(+2)-Pt(+2)- with direct metal-metal bonds was obtained via HOMO-LUMO interactions at the σ* (dz2) orbital between [Rh2(O2CCH3)4] and [Pt2Ni(piam)4(NH3)4] (piam=pivalamidate). The one-dimensional chains had straight backbones attributed to face-to-face stacking of each complex, and the Ni atoms were separated by approximately 13 Šfrom four different metals. Each Ni atom had two unpaired electrons in the d-orbitals, which strongly exchanged with J=-37.9 cm-1 through the diamagnetic -Pt-Rh-Rh-Pt- bonds.

Evaluating the psychometric properties of two-item and four-item short forms of the Japanese Pain Self-Efficacy Questionnaire: a cross-sectional study.

PURPOSE: The Pain Self-Efficacy Questionnaire is a valid measure assessing self-efficacy in individuals with chronic pain. Short-form versions of the measure have been developed to decrease the assessment burden. However, few studies have evaluated the psychometric properties of the short forms in languages other than English. The aim of this study was to evaluate two 2-item short forms and one 4-item short form of the Japanese Pain Self-Efficacy Questionnaire in terms of internal consistency, criterion validity, structural validity, and construct validity. METHODS: This was a cross-sectional study. Data from 150 individuals with mixed chronic pain at a pain management center in a university hospital were extracted from clinical records and analyzed. The data included the information of the original version and short forms of the Japanese Pain Self-Efficacy Questionnaire, and other pain-related measures assessing pain intensity, pain interference, anxiety, depression and pain catastrophizing. RESULTS: Item statistics supported the item selection for each of the three short forms. All the short forms demonstrated adequate internal consistency and criterion validity. With respect to construct validity, one of the 2-item short forms failed to meet the criterion regarding the change in the magnitude of correlation with a depression scale. The 4-item short form met all the criteria including structural validity. CONCLUSION: The study findings provide evidence for the reliability and validity of 2- and 4-item versions of the Japanese Pain Self-Efficacy Questionnaire for use in clinical and research settings.

The Relationships Between Pain-Catastrophizing Subcomponents and Multiple Pain-Related Outcomes in Japanese Outpatients with Chronic Pain: A Cross-Sectional Study.

OBJECTIVES: The present study sought to examine associations between the pain-catastrophizing subcomponents and multiple pain-related outcomes in Japanese individuals with chronic pain. METHODS: A cross-sectional study design was employed with 213 chronic pain outpatients. The participants were recruited from 3 units at a university hospital and from a pain clinic at a municipal hospital. Study measures were used to assess pain catastrophizing, anxiety, depression, pain interference, and pain severity. RESULTS: Path analysis with multiple pain-related outcomes while controlling for age and gender revealed that the Helplessness subcomponent was associated with anxiety, depression, pain interference, and pain severity. The Magnification subcomponent was related to anxiety and depression, and the Rumination subcomponent accounted for the variance of pain interference. DISCUSSION: The present results suggested the important role of helplessness across cultural backgrounds. It also provides guidance on the application of cognitive behavioral techniques for chronic pain management in Japan.

A Cross-Cultural Validation of the Multidimensional Pain Readiness to Change Questionnaire 2 for Japanese Individuals With Chronic Pain.

OBJECTIVES: The Multidimensional Pain Readiness to Change Questionnaire 2 (MPRCQ2) is a reliable and valid measure that assesses readiness to adopt a variety of discrete pain self-management responses. We sought to translate and evaluate psychometric properties of the Japanese version of the MPRCQ2 (MPRCQ2-J) in individuals with chronic pain. METHODS: One hundred seventy-three individuals with chronic pain were asked to complete the MPRCQ2-J, as well as measures assessing pain intensity, pain interference, self-efficacy, and general readiness to adopt a self-management approach for pain. Forty-eight of these participants provided additional MPRCQ2-J data to assess test-retest reliability. RESULTS: The findings supported a 2-factor structure of the MPRCQ2-J when error covariances between the some of the nine primary scales were allowed. Adequate internal consistencies of the MPRCQ2-J scales (Cronbach's α ranged 0.71 to 0.86), except for the total score (α = 0.68), were observed. However, adequate test-retest reliabilities (intraclass correlation coefficients ≥ 0.60) were found for only 59% of the MPRCQ2-J scales. The MPRCQ2-J evidenced its construct validity via confirmation of the predicted patterns of associations with validity criterion measures and the anticipated effects of participation in an exercise treatment. DISCUSSION: The findings support the internal consistency (except for the total score) and construct validity for MPRCQ2-J scales. However, potential limitations with respect to test-retest reliability of some of the scales were also suggested. The MPRCQ2-J can be used to examine the role that specific readiness domains of pain self-management responses may play in an adjustment process in Japanese individuals with chronic pain.

Brain Oscillations, Hypnosis, and Hypnotizability.

This article summarizes the state-of-science knowledge regarding the associations between hypnosis and brain oscillations. Brain oscillations represent the combined electrical activity of neuronal assemblies, usually measured as specific frequencies representing slower (delta, theta, alpha) and faster (beta, gamma) oscillations. Hypnosis has been most closely linked to power in the theta band and changes in gamma activity. These oscillations are thought to play a critical role in both the recording and recall of declarative memory and emotional limbic circuits. The authors propose that this role may be the mechanistic link between theta (and perhaps gamma) oscillations and hypnosis, specifically, that the increases in theta oscillations and changes in gamma activity observed with hypnosis may underlie some hypnotic responses. If these hypotheses are supported, they have important implications for both understanding the effects of hypnosis and for enhancing response to hypnotic treatments.

Brain Oscillations, Hypnosis, and Hypnotizability.

In this article, we summarize the state-of-science knowledge regarding the associations between hypnosis and brain oscillations. Brain oscillations represent the combined electrical activity of neuronal assemblies, and are usually measured as specific frequencies representing slower (delta, theta, alpha) and faster (beta, gamma) oscillations. Hypnosis has been most closely linked to power in the theta band and changes in gamma activity. These oscillations are thought to play a critical role in both the recording and recall of declarative memory and emotional limbic circuits. Here we propose that it is this role that may be the mechanistic link between theta (and perhaps gamma) oscillations and hypnosis; specifically that theta oscillations may facilitate, and that changes in gamma activity observed with hypnosis may underlie, some hypnotic responses. If these hypotheses are supported, they have important implications for both understanding the effects of hypnosis, and for enhancing response to hypnotic treatments.

Validation of the Japanese version of the pain self-efficacy questionnaire in Japanese patients with chronic pain.

OBJECTIVES: The present study aimed to develop the Japanese version of the Pain Self-Efficacy Questionnaire (PSEQ-J) and to evaluate its psychometric properties. DESIGN: Cross-sectional design. SETTING: A pain clinic, a neurosurgery unit, and an orthopedic surgery unit in one university hospital and a pain clinic in a municipal hospital. METHODS: One hundred and seventy-six participants completed study measures, which included 1) the PSEQ-J, 2) the Hospital Anxiety and Depression Scale, 3) the Pain Catastrophizing Scale, 4) the Medical Outcome Study Short-Form 36, 5) the Pain Disability Assessment Scale, and 6) the Short-Form McGill Pain Questionnaire. RESULTS: The PSEQ-J demonstrated adequate reliability and validity. Hierarchical multiple regression analyses showed that pain self-efficacy as measured with the PSEQ-J accounted for a significant proportion of the variance on the measures administered in the present study. The PSEQ-J was most strongly associated with social activity. CONCLUSIONS: The results demonstrated that the PSEQ-J has adequate psychometric properties, supporting its use in clinical and research settings and suggest that the PSEQ-J may be particularly strongly associated with more social and less physical activity.

Associations between anger and chronic primary pain: a systematic review and meta-analysis.

OBJECTIVES: Anger is a negative emotion characterized by antagonism toward someone or something, is rooted in an appraisal or attribution of wrongdoing, and is accompanied by an action tendency to undo the wrongdoing. Anger is prevalent in individuals with chronic pain, especially those with chronic primary pain. The associations between anger and pain-related outcomes (e.g., pain intensity, disability) have been examined in previous studies. However, to our knowledge, no systematic review or meta-analysis has summarized the findings of anger-pain associations through a focus on chronic primary pain. Hence, we sought to summarize the findings on the associations of anger-related variables with pain and disability in individuals with chronic primary pain. METHODS: All studies reporting at least one association between anger-related variables and the two pain-related outcomes in individuals with chronic primary pain were eligible. We searched electronic databases using keywords relevant to anger and chronic primary pain. Multiple reviewers independently screened for study eligibility, data extraction, and methodological quality assessment. RESULTS: Thirty-eight studies were included in this systematic review, of which 20 provided data for meta-analyses (2,682 participants with chronic primary pain). Of the included studies, 68.4% had a medium methodological quality. Evidence showed mixed results in the qualitative synthesis. Most anger-related variables had significant positive pooled correlations with small to moderate effect sizes for pain and disability. CONCLUSIONS: Through a comprehensive search, we identified several key anger-related variables associated with pain-related outcomes. In particular, associations with perceived injustice were substantial.

Comparison of the effectiveness of cognitive behavioral therapy for insomnia, cognitive behavioral therapy for pain, and hybrid cognitive behavioral therapy for insomnia and pain in individuals with comorbid insomnia and chronic pain: A systematic review and network meta-analysis.

Considering that insomnia and chronic pain are often comorbid, we aimed to compare the effectiveness of cognitive behavioral therapy for insomnia (CBT-I), cognitive behavioral therapy for pain (CBT-P), and cognitive behavioral therapy for insomnia and pain (CBT-IP) in individuals with comorbid insomnia and chronic pain. We used PubMed, PsycINFO, CENTRAL, and Web of Science for our literature search. The outcomes included sleep, pain, disability, and depression at post-treatment and follow-up (3-12 months). Sixteen randomized controlled trials with 1094 participants were included. In the Bayesian network meta-analysis, CBT-I [standard mean difference (SMD) = -0.99, 95% credible interval (CrI) = -1.50 to -0.54] and CBT-IP (SMD = -0.70, 95% CrI = -1.60 to -0.08) were significantly more effective than the control for sleep at post-treatment. Additionally, CBT-I was significantly more effective than the control for pain, disability, and depression at post-treatment and sleep at follow-up. However, there were no significant differences in effectiveness between CBT-P and the control for any outcomes. Thus, CBT-I might be the most effective treatment option for individuals with comorbid insomnia and chronic pain. However, given the small sample sizes and high risk of bias of the included studies, these results must be interpreted with caution.

Validation of the Japanese version of the patterns of activity measure-pain in individuals with chronic pain.

BACKGROUND: The Patterns of Activity Measure-Pain (POAM-P) is a self-report questionnaire that measures avoidance, overdoing, and pacing in individuals with chronic pain. We aimed to develop and confirm the psychometric properties of the Japanese version of the POAM-P(POAM-P-J) in Japanese individuals with chronic pain. METHODS: We recruited 147 Japanese individuals with chronic pain (106 women; mean age 64.89 ± 12.13 years). The individuals completed the POAM-P-J, the Brief Pain Inventory (BPI), and the Hospital Anxiety and Depression Scale (HADS). The following psychometric properties of the POAM-P-J were confirmed: structural validity, internal consistency, test-retest reliability, and concurrent validity. RESULTS: We tested factor structure via confirmatory factor analyses (CFA). We chose the 3-factor model with six covariances. The POAM-P-J's internal consistency and test-retest reliability were acceptable to good (α = 0.79-0.86; ICC = 0.72-0.87). The avoidance and overdoing subscales were positively associated with pain severity, pain interference, and anxiety measures (all p < 0.05), but the pacing subscale was not significantly associated with these pain-related measures. CONCLUSIONS: Although the structural validity of the POAM-P-J remains questionable, its internal consistency, test-retest reliability, and concurrent validity were confirmed. The POAM-P-J is useful in both research and clinical practice for evaluating the activity patterns of Japanese patients with chronic pain.

Pilot study of a basic individualized cognitive behavioral therapy program for chronic pain in Japan.

BACKGROUND: Chronic pain is a major health problem, and cognitive behavioral therapy (CBT) is its recommended treatment; however, efforts to develop CBT programs for chronic pain and assess their feasibility are remarkably delayed in Asia. Therefore, we conducted this pilot study to develop a basic individualized CBT for chronic pain (CBT-CP) and assessed its feasibility for use in Japan. METHODS: Our study was an open-labeled before-after trial without a control group conducted cooperatively in five Japanese tertiary care hospitals. Of 24 outpatients, 15, age 20-80, who experienced chronic pain for at least three months were eligible. They underwent an eight-session CBT-CP consisting of relaxation via a breathing method and progressive muscle relaxation, behavioral modification via activity pacing, and cognitive modification via cognitive reconstruction. The EuroQol five-dimensional questionnaire five level (EQ5D-5 L) assessment as the primary outcome and quality of life (QOL), pain severity, disability, catastrophizing, self-efficacy, and depressive symptoms as secondary outcomes were measured using self-administered questionnaires at baseline, post-treatment, and 3-month follow-up. Intention-to-treat analyses were conducted. RESULTS: Effect size for EQ5D-5 L score was medium from baseline to post-treatment (Hedge's g = - 0.72, 90% confidence interval = - 1.38 to - 0.05) and up to the 3-month follow-up (g = - 0.60, CI = - 1.22 to 0.02). Effect sizes for mental and role/social QOL, disability, catastrophizing, self-efficacy, and depressive symptoms were medium to large, although those for pain severity and physical QOL were small. The dropout rate was acceptably low at 14%. No severe adverse events occurred. CONCLUSION: The findings suggest that CBT-CP warrants a randomized controlled trial in Japan. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR), UMIN000020880. Registered on 04 February 2016.

Developing a Japanese version of the Injustice Experience Questionnaire-chronic and the contribution of perceived injustice to severity of menstrual pain: a web-based cross-sectional study.

BACKGROUND: Menstrual pain causes low quality of life among women of reproductive age, and often interferes with daily activities. Perceived injustice is a cognition linked to adverse symptoms. The aims of this study were to develop a Japanese version of the Injustice Experience Questionnaire-chronic (IEQ-chr-J), and to examine if perceived injustice is associated with pain intensity and impairment from menstruation. METHODS: We investigated 130 Japanese women (aged 20-45 years) with menstrual pain in the past 3 months using online self-administered questionnaires. We examined the psychometric properties of the IEQ-chr-J including: structural validity; internal consistency; and test-retest reliability (intra-class correlation coefficients; ICC). Concurrent validity was examined by correlations among the IEQ-chr-J, the Pain Catastrophizing Scale (PCS), the Hospital Anxiety and Depression Scale (HADS), a numerical rating scale (NRS) for maximum/average menstrual pain, and the Brief Pain Inventory (BPI) pain interference domain. We used multivariable regression analysis to investigate the association between perceived injustice and severity of menstrual pain, after excluding 10 hormone drug users. RESULTS: The IEQ-chr-J showed sufficient validity and reliability (Cronbach's α = 0.96, ICC 0.75, [95% confidence interval (CI): 0.61-0.88]. Pearson's correlation coefficients for the IEQ-chr-J, PCS, HADS anxiety, HADS depression, NRS, and BPI pain interference ranged from 0.27-0.65. The IEQ-chr-J was correlated with impairment due to menstrual pain (ICC 0.36, 95% CI: 0.14-0.58), an independent diagnosis of endometriosis, anxiety, and depression, but not with maximum or average pain intensity. CONCLUSIONS: The IEQ-chr-J has acceptable psychometric properties, and perceived injustice is associated with impairment from menstrual pain.

Japanese cross-cultural validation study of the Pain Stage of Change Questionnaire.

INTRODUCTION: Although evidence supports efficacy of treatments that enhance self-management of chronic pain, the efficacy of these treatments has been hypothesized to be influenced by patient readiness for self-management. The Pain Stage of Change Questionnaire (PSOCQ) is a reliable and valid measure of patient readiness to self-manage pain. However, there is not yet a Japanese version of the PSOCQ (PSOCQ-J), which limits our ability to evaluate the role of readiness for pain self-management in function and treatment response in Japanese patients with chronic pain. OBJECTIVE: Here, we sought to develop the PSOCQ-J and evaluate its psychometric properties. METHODS: We recruited 201 patients with chronic pain. The study participants were asked to complete the PSOCQ-J and other measures assessing pain severity, pain interference, catastrophizing, self-efficacy, and pain coping strategies. RESULTS: The results supported a 4-factor structure of the PSOCQ-J. We also found good to excellent internal consistencies and good test-retest reliabilities for the 4 scales. The Precontemplation scale had weak to moderate positive correlations with measures of pain-related dysfunction and maladaptive coping. The Action and Maintenance scales had weak to moderate positive correlations with measures of self-efficacy and adaptive coping. The Contemplation scale had weak positive correlations with measures of pain interference and both adaptive and maladaptive coping. CONCLUSIONS: The PSOCQ-J demonstrated adequate psychometric properties in a sample of Japanese patients with chronic pain. This measure can be used to evaluate the role that readiness to self-manage pain may play in adjustment to chronic pain in Japanese pain populations.

Reliability and validity of the Athens Insomnia Scale in chronic pain patients.

PURPOSE: To confirm the psychometric properties of the Athens Insomnia Scale (AIS) among Japanese chronic pain patients. PATIENTS AND METHODS: In total, 144 outpatients were asked to complete questionnaires comprising the AIS and other study measures. According to the original article, the AIS has 2 versions: the AIS-8 (full version) and the AIS-5 (brief version). To validate the AIS-8 and AIS-5 among chronic pain patients, we confirmed: 1) factor structure by confirmatory factor analysis; 2) internal consistency by Cronbach's a; 3) test-retest reliability using with interclass correlation coefficients; 4) known-group validity; 5) concurrent validity; and 6) cut-off values by receiver operating characteristic analysis. In addition, semi-structured interviews were conducted to assess the participants' sleep disturbance. If the participants had any sleep complaints, including difficulty in initiating sleep, difficulty in maintaining sleep, and early morning awakening, they were defined as insomnia symptoms. RESULTS: A 2-factor model of the AIS-8 and 1-factor model of the AIS-5 demonstrated good fit. The AIS had adequate internal consistency and test-retest reliability. Patients with insomnia had a higher AIS score than those without insomnia. The sleep disturbance measured by the AIS was positively associated with pain intensity, disability, depression, anxiety, and pain catastrophizing, and negatively associated with pain-related self-efficacy. The cut-off values for detecting insomnia were estimated at 8 points in the AIS-8 and 4 points in the AIS-5. CONCLUSION: The AIS-8 and AIS-5 had adequate reliability and validity in chronic pain patients.

Effects of a Hypnotic Induction and an Unpleasantness-Focused Analgesia Suggestion on Pain Catastrophizing to an Experimental Heat Stimulus: A Preliminary Study.

Pain catastrophizing is associated with greater levels of pain. While many studies support the efficacy of hypnosis for pain, the effect on pain catastrophizing remains unclear. The present study evaluated the effect of hypnosis on pain catastrophizing using experimental heat stimulation. Twenty-two pain patients engaged in 3 conditions: baseline (no suggestion), hypnotic induction, and hypnotic induction plus analgesia suggestion. Participants with higher baseline pain showed a significant reduction in rumination following hypnotic induction plus analgesia suggestion and significant reductions in pain due to both the hypnotic induction alone and the hypnotic induction plus analgesia suggestion. The findings suggest that unpleasantness-focused hypnotic analgesia reduces pain via its effect on the rumination component of pain catastrophizing.

Injustice Experience Questionnaire, Japanese Version: Cross-Cultural Factor-Structure Comparison and Demographics Associated with Perceived Injustice.

OBJECTIVE: The Injustice Experience Questionnaire (IEQ) assesses injury-related perceived injustice. This study aimed to (1) develop a Japanese version (IEQ-J), (2) examine its factor structure, validity, and reliability, and (3) discover which demographic variable(s) positively contributed to prediction of IEQ-J scores. METHODS: Data from 71 patients (33 male, 38 female; age = 20+) with injury pain were employed to investigate factor structure by exploratory and confirmatory factor analyses. Concurrent validity was examined by Pearson correlation coefficients among the IEQ-J, Brief Pain Inventory (BPI), and Pain Catastrophizing Scale (PCS). Internal consistency was investigated by Cronbach's alpha, and test-retest reliability was indicated with intra-class correlations (ICCs) in 42 of 71 patients within four weeks. Relations between demographic variables and IEQ-J scores were examined by covariance analysis and linear regression models. RESULTS: IEQ-J factor structure differed from the original two-factor model. A three-factor model with Severity/irreparability, Blame/unfairness, and Perceived lack of empathy was extracted. The three-factor model showed goodness-of-fit with the data and sufficient reliability (Cronbach's alpha of 0.90 for total IEQ-J; ICCs = 0.96). Pearson correlation coefficients among IEQ-J, BPI, and PCS ranged from 0.38 to 0.73. Pain duration over a year (regression coefficient, 11.92, 95%CI; 5.95-17.89) and liability for injury on another (regression coefficient, 12.17, 95%CI; 6.38-17.96) predicted IEQ-J total scores. CONCLUSIONS: This study evidenced the IEQ-J's sound psychometric properties. The three-factor model was the latter distinctive in the Japanese version. Pain duration over a year and injury liability by another statistically significantly increased IEQ-J scores.

Mechanisms of hypnosis: toward the development of a biopsychosocial model.

Evidence supports the efficacy of hypnotic treatments, but there remain many unresolved questions regarding how hypnosis produces its beneficial effects. Most theoretical models focus more or less on biological, psychological, and social factors. This scoping review summarizes the empirical findings regarding the associations between specific factors in each of these domains and response to hypnosis. The findings indicate that (a) no single factor appears primary, (b) different factors may contribute more or less to outcomes in different subsets of individuals or for different conditions, and (c) comprehensive models of hypnosis that incorporate factors from all 3 domains may ultimately prove to be more useful than more restrictive models that focus on just 1 or a very few factors.

A meta-analysis of hypnosis for chronic pain problems: a comparison between hypnosis, standard care, and other psychological interventions.

Hypnosis is regarded as an effective treatment for psychological and physical ailments. However, its efficacy as a strategy for managing chronic pain has not been assessed through meta-analytical methods. The objective of the current study was to conduct a meta-analysis to assess the efficacy of hypnosis for managing chronic pain. When compared with standard care, hypnosis provided moderate treatment benefit. Hypnosis also showed a moderate superior effect as compared to other psychological interventions for a nonheadache group. The results suggest that hypnosis is efficacious for managing chronic pain. Given that large heterogeneity among the included studies was identified, the nature of hypnosis treatment is further discussed.

The influence of working memory capacity on experimental heat pain.

UNLABELLED: Pain processing and attention have a bidirectional interaction that depends upon one's relative ability to use limited-capacity resources. However, correlations between the size of limited-capacity resources and pain have not been evaluated. Working memory capacity, which is a cognitive resource, can be measured using the reading span task (RST). In this study, we hypothesized that an individual's potential working memory capacity and subjective pain intensity are related. To test this hypothesis, we evaluated 31 healthy participants' potential working memory capacity using the RST, and then applied continuous experimental heat stimulation using the listening span test (LST), which is a modified version of the RST. Subjective pain intensities were significantly lower during the challenging parts of the RST. The pain intensity under conditions where memorizing tasks were performed was compared with that under the control condition, and it showed a correlation with potential working memory capacity. These results indicate that working memory capacity reflects the ability to process information, including precise evaluations of changes in pain perception. PERSPECTIVE: In this work, we present data suggesting that changes in subjective pain intensity are related, depending upon individual potential working memory capacities. Individual working memory capacity may be a phenotype that reflects sensitivity to changes in pain perception.