[Avoidance-endurance fast screen : AEFS validation with one- and two-level response scaling in healthy subjects]. / Avoidance-Endurance Fast-Screen (AEFS) : Validierung des AEFS mit ein- und zweistufiger Antwortskalierung an Gesunden.

BACKGROUND AND OBJECTIVES: Chronic pain affects an enormous number of patients in Germany. Therefore, early detection is important using easy, quick and reasonable screening methods. The avoidance-endurance fast screen is currently available in two different versions: one asking for pain-related behaviour in light and severe pain and the other assessing overall severe pain-related behaviour. In this study we aim to examine the agreement between both scales and for the first time describe the role of protective psychological features such as resilience and self-compassion in this model. MATERIALS AND METHODS: Epidemiological cross-sectional study (n = 278) of a healthy cohort occasionally experiencing pain (< 3 months). The analysis was done using standard descriptive statistics, correlations (Spearman's rho) and deductive statistics (t-tests and one-factor ANOVA with post hoc Bonferroni correction) and effect sizes (Cohen's d). Matching of the instruments was calculated with Cohen's kappa. RESULTS: The results showed a moderate agreement for the two versions. A validity check of the subgroups resulted in comparable findings. The one-level version scored higher in terms of pain persistence which caused subgroup changes from adaptive to eustress-endurance responses and from fear-avoidance to distress-endurance responses. The distress-endurance subgroup had significantly lower values of the trait self-compassion. CONCLUSIONS: Based on the results of this study, the quality of agreement between the two AEFS versions is considered strong. Without the comparison between mild and strong pain, endurance behaviour was reported more often. According to these findings, overestimation of pain persistence behaviour using the one-level version might result. Therefore, future studies should re-evaluate the cut-offs. As reported in previous studies, protective psychological features showed the highest scores in the eustress-endurance subgroup.

[Psychosocial factors in pain and pain management : A statement]. / Psychosoziale Faktoren bei Schmerz und Schmerzbehandlung : Eine Positionsbestimmung.

Although psychosocial factors have a profound impact on the experience of pain and pain recovery, the transfer to clinical application has so far been insufficient. With this article, a task force of the special interest group "Psychosocial Aspects of Pain" of the German Pain Society (Deutsche Schmerzgesellschaft e. V.) would like to draw attention to the considerable discrepancy between existing scientific evidence on the importance of psychosocial factors in the development of chronic pain disorders and the translation of these findings into the care of pain patients. Our objective is a stronger integration of psychological and psychosomatic expertise in pain treatment and research, as well as the improvement of structural and institutional conditions, to achieve an increased consideration of psychosocial aspects. In this way, modern, integrative and complex pain concepts can reach the patient. Based on these fundamental findings on the importance of psychosocial factors in pain and pain treatment, implications for the transfer to clinic and further research will be shown.

Body Image in Athletes and Nonathletes With Low Back Pain: Avoidance-Endurance-Related Subgroups and Sports Status Play a Role.

CONTEXT: Low back pain (LBP) is a serious health problem, both in the general population as well as in athletes. Research has shown that psychosocial aspects, such as dysfunctional pain responses, play a significant role in the chronification of LBP. Recent research supports the relevance of the multidisciplinary concept of body image in the interpretation of LBP. OBJECTIVE: To examine the differences in 2 psychosocial aspects, body image and pain responses, between athletes and nonathletes with LBP. DESIGN: Cross-sectional design. SETTING: The questionnaires were distributed in the course of LBP treatment. PARTICIPANTS: Data from 163 athletes (mean age = 28.69 [9.6] y) and 75 nonathletes (mean age = 39.34 [12.63] y) were collected. INTERVENTIONS: Data were collected by questionnaires assessing body image, pain behavior, training activity, and LBP. MAIN OUTCOME MEASURES: To examine group differences between athletes and nonathletes regarding body image and pain behavior, the authors performed 2-way analyses of variance with Bonferroni post hoc tests. RESULTS: The results showed (1) a significant main effect regarding pain responses and body image, showing that participants with eustress endurance or adaptive pain behavior revealed a more positive body image in both groups compared with participants with distress endurance or fear-avoidance behavior, and (2) a significant main effect for the factor group in the body image dimension of physical efficacy, indicating a more positive body image for athletes. CONCLUSION: These results suggest that considering multiple risk factors for LBP, such as body image and dysfunctional pain behavior, as well as subgrouping, might be valuable for research and for broadening therapy options.

Assessing Endogenous Pain Inhibition: Test-Retest Reliability of Exercise-Induced Hypoalgesia in Local and Remote Body Parts After Aerobic Cycling.

OBJECTIVE: Acute exercise can trigger a hypoalgesic response (exercise-induced hypoalgesia [EIH]) in healthy subjects. Despite promising application possibilities of EIH in the clinical context, its reliability has not been sufficiently examined. This study therefore investigated the between-session and within-subject test-retest reliability of EIH at local and remote body parts after aerobic cycling at a heart rate-controlled intensity. METHODS: Thirty healthy adults (15 women) performed 15 minutes of aerobic cycling in two sessions. Pressure pain thresholds (PPTs) were assessed at the leg (local), the back (semilocal), and the hand (remote) before, immediately after, and 15 minutes after exercise. Intraclass correlation coefficients (ICCs) were calculated for absolute and percent changes in PPT from baseline to immediately postexercise, and between-session agreement of EIH responders was examined. RESULTS: PPTs significantly increased at the leg during both sessions (all P < 0.001) and at the back during session 2 (P < 0.001), indicating EIH. Fair between-session reliability was shown for absolute changes at the leg (ICC = 0.54) and the back (ICC = 0.40), whereas the reliability of percent changes was poor (ICC < 0.33). Reliability at the hand was poor for both absolute and percent changes (ICC < 0.33). Agreement in EIH responders was not significant for EIH at the leg or the back (all P > 0.05). CONCLUSIONS: Our results suggest fair test-retest reliability of EIH after aerobic cycling for local and semilocal body parts, but only in men, demonstrating the need for more standardized methodological approaches to improve EIH as a clinical parameter.

Pain-related avoidance and endurance behaviour in migraine: an observational study.

BACKGROUND: The role of avoidance and endurance behaviour is well established in chronic musculoskeletal pain, but less is known about its significance in migraine. METHODS: The Avoidance-Endurance Questionnaire behavioural subscales, the Pain Disability Index (PDI), the Migraine Disability Assessment Scale (MIDAS) and the Hospital Anxiety and Depression Scale (HADS) were obtained from 128 migraine patients (90 episodic, 38 chronic). Sixty nine of them were re-evaluated after 3-6 months. RESULTS: At baseline, there were positive relations between avoidance (especially social avoidance behaviour) and pain-related disability as assessed by the PDI (Wald χ2 [1] = 32.301, p < 0.001) and the MIDAS (Wald χ2 [1] = 14.387, p < 0.001). A negative relation of endurance behaviour with PDI scores did not survive multiple regression analysis. In addition, there was a positive relation of social avoidance with the HADS depression score (Wald χ2 [1] = 3.938, p = 0.047) and a negative relation of endurance (especially the humour-distraction subscale) with the HADS anxiety score (Wald χ2 [1] = 6.163, p = 0.013). Neither avoidance nor endurance were related to headache intensity or frequency, or to a diagnosis of episodic vs. chronic migraine. 3-6 months after treatment at our headache centre, headache frequency, intensity and pain-related disability were significantly improved (all p < 0.01) while avoidance and endurance were unchanged. CONCLUSIONS: This indicates that improvement in headache frequency and disability can be achieved in the absence of changes in avoidance or endurance behaviour. However, because of its significant link to headache-related disability, avoidance behaviour (especially social avoidance) should be investigated as a potential additional target of migraine therapy.

Examining the Presence of Back Pain in Competitive Athletes: A Focus on Stress and Recovery.

CONTEXT: Explanatory approaches for back pain (BP) in athletes focus on biomechanical factors while neglecting psychological perspectives. Psychological factors have gained importance in the prediction of injuries in athletes and BP in the general population, with stress and recovery emerging as central risk factors. However, scarce evidence exists regarding the role of these aspects for the prevalent burden of BP. OBJECTIVE: To investigate the association between stress and recovery parameters and the presence of BP. DESIGN: Cross-sectional design. SETTING: The questionnaires were distributed after the training sessions. PARTICIPANTS: A total of 345 competitive athletes (mean age = 18.31 y [SD = 5.40]) were investigated. The classification of the athletes' competitive status was based on performance level. INTERVENTIONS: Data were collected using questionnaires for the assessment of stress, recovery, and BP. MAIN OUTCOME MEASURES: The authors performed a multiple logistic regression to obtain odds ratios for stress and recovery parameters with regard to the outcome variable BP status. RESULTS: For stress, the dimension "overall stress" (odds ratio = 1.83; 95% confidence interval, 1.30-2.59; P = .001) and the scale "physical complaints" (odds ratio = 1.68; 95% confidence interval, 1.25-2.25; P = .001) of the general version of the Recovery-Stress Questionnaire resulted to be significantly associated with BP. None of the recovery-related scales displayed a statistically significant relationship with BP. CONCLUSION: The outcomes of this study imply a modest association between stress and the presence of BP in competitive athletes. Practitioners may take these findings into account regarding the conception of training and for monitoring purposes.

Correction to: Mild Depression in Low Back Pain: the Interaction of Thought Suppression and Stress Plays a Role, Especially in Female Patients.

This article was updated to correct the author names. Family and given names are in the correct order.

Mild Depression in Low Back Pain: the Interaction of Thought Suppression and Stress Plays a Role, Especially in Female Patients.

PURPOSE: Mild depression has been shown as a precursor and as a consequence of low back pain, even in early phases of acute or subacute pain. Chronic daily life stress as well as dysfunctional pain-related cognitions such as thought suppression (TS) seem to play a role in the pain-depression cycle; however, the mechanisms of these associations are less understood. Experimentally induced TS, conceived as the attempt to directly suppress sensations such as pain, has been shown to paradoxically cause a delayed and non-volitional return of the suppressed thoughts and sensations and to increase affective distress. These dysfunctional processes are supposed to increase under high cognitive load, such as high stress. METHOD: In the present cross-sectional study, we for the first time sought to examine a possible interaction between habitual TS and stress on depression in N = 177 patients with subacute low back pain (SLBP), using the following questionnaires: Subscale Thought Suppression from Avoidance-Endurance Questionnaire, Beck Depression Inventory, and Kiel Interview of Subjective Situation. A three-way ANOVA was conducted with two groups of TS (high/low), stress (high/low) and sex as independent factors and depression as dependent. RESULTS: Results indicated a significant three-way interaction with highest depression scores in female patients showing high TS and high stress. Overall main effects for sex and stress indicated higher depression in women and in highly stressed patients. CONCLUSION: Our findings support the hypothesis that TS heightens depressive mood under conditions of high cognitive load especially in female patients with SLBP indicating a special vulnerability for depressive mood in women with SLBP.

Isometric Back Exercise Has Different Effect on Pressure Pain Thresholds in Healthy Men and Women.

Objective: Isometric exercises produce an acute decrease in the pain sensitivity, known as exercise-induced hypoalgesia (EIH). Existing EIH paradigms use exercises at the extremities with more pronounced EIH at local compared to remote body sites, indicating local inhibition in addition to central inhibitory mechanisms. So far the results on EIH in patients with low back pain (LBP) are equivocal and no studies have investigated an EIH paradigm targeting the lower back in order to assess EIH in patients with LBP. Thus, the aim of this pilot study was to assess pressure pain sensitivity at local and remote assessment sites, before and after an isometric back exercise in healthy women and men. Methods: In a pre-posttest design, pressure pain thresholds (PPT) were assessed at the lower back, biceps femoris muscle, and hand in 29 healthy subjects (17 women) before and after 120 seconds of the isometric Biering-Soerensen back extension test. Results: After exercise, PPT increased significantly at the hand in women, but not in men ( P = 0.027). Moreover, PPT at the leg increased independently of sex ( P < 0.004). The increase in PPT at the lower back after exercise approached significance ( P = 0.07). Conclusions: The results of this pilot study indicate that isometric back exercise produces local and remote hypoalgesia. Remote EIH was only demonstrated in women, supporting the influence of sex in the hypoalgesic response after exercise. The effect of isometric back exercise on pain sensitivity in patients with low back pain should be investigated in future studies.

Recall Bias in Patients with Chronic Low Back Pain: Individual Pain Response Patterns Are More Important Than Pain Itself!

BACKGROUND: Patients' cognitive processing of pain-related information as well as their cognitive, affective and behavioral response pattern when experiencing pain in daily life has been shown to be associated with poorer prognosis in low back pain. However, the relationship between specific cognitive processes such as recall of pain-related material and individual pain responses remains unknown. PURPOSE: The present study sought to investigate recall bias in patients with chronic low back pain (CLBP) compared to healthy controls. Furthermore, it was aimed to investigate the impact of patients' individual pain-related responses on recall bias, comparing fear-avoidance response (FAR), endurance response (ER) and adaptive response (AR) patterns. METHOD: Thirty-one CLBP patients and 31 controls were tested on a free recall task with three word lists comprising pain words and neutral words. Further, the CLBP group was classified into patients with a FAR, ER and AR pattern, using a short screening including the Avoidance-Endurance Questionnaire (AEQ). Group differences with pain status (CLBP vs. healthy) and AEQ responses (FAR, ER, AR) as between-group factors, word type (pain vs. neutral) as within-group factor and free recall as dependent variable were analysed by means of repeated-measures analysis of (co-) variance. RESULTS: Results revealed different pain processing of pain words between FAR and ER patterns, whereas CLBP patients as a whole did not differ from the healthy controls. FAR patients displayed significantly less recall than ER patients. CONCLUSION: Recall biases in CLBP patients are not only a result of experiencing pain but also effected by patients' pain response pattern with respect to fear-avoidance versus endurance.

Understanding Pain and Depression in Back Pain: the Role of Catastrophizing, Help-/Hopelessness, and Thought Suppression as Potential Mediators.

PURPOSE: The cognitive mediation hypothesis describes the influence of psychological factors on the relationship between pain and depression such as cognitions of catastrophizing and help-/hopelessness. More recent research also emphasizes the role of suppression of negative thoughts and experiences such as pain. However, there is little research investigating direct and indirect effects of these contrasting cognitions. METHOD: A total of 164 acute and sub-acute non-specific back pain patients participated in this study. Pain intensity, depression, and pain-related cognitions were measured using questionnaires, such as the Beck Depression Inventory and the Kiel Pain Inventory. Data were analyzed using structural equation modeling. RESULTS: The results of the path analysis support the hypothesis that cognitive coping strategies have a mediating effect on pain and depression. Consistent with previous research, we found that pain had no direct relation with depression. Help-/hopelessness had a direct path to depression, whereas catastrophizing had an indirect effect via increased help-/hopelessness. The current results also indicate that thought suppression mediated the relationship between pain and depression via both direct and indirect effects. CONCLUSION: Cognitive mediators, such as help-/hopelessness, catastrophizing, and thought suppression, have a significant impact on depression in patients with acute and sub-acute back pain. The current results may aid in the optimization of treatments for these patients by focusing attention toward the modification of dysfunctional cognitive pain-coping strategies.

The German PASS-20 in patients with low back pain: new aspects of convergent, divergent, and criterion-related validity.

BACKGROUND: The PASS-20 (McCracken and Dhingra, Pain Res Manag 7:45-50, 2002) is a shortened version of the Pain Anxiety Symptoms Scale (PASS), a self-report measure of pain anxiety. The PASS-20 demonstrates good psychometric characteristics but has not yet been validated in a German population. PURPOSE: The aims of the present study were to (1) examine the factor structure and psychometric characteristics of the German PASS-20; (2) investigate its construct validity with respect to depression, fear-avoidance, and endurance; and (3) determine its criterion-related validity with a special emphasis on pain, disability, and quality of life. METHOD: A principal component analysis was performed on a sample (N = 195) of patients with acute, subacute, and chronic low back pain. Reliability was examined with Cronbach's α. Validity was assessed by correlating the PASS-20 to measures of depression, anxiety, disability, quality of life, and avoidance-endurance-related behavioral pain responses. RESULTS: The original four-factor structure proposed for the PASS-20 was replicated using the original subscale labels. The reliability of the total score and the subscales was satisfactory to excellent, and both convergent and divergent validity were moderate to high in the expected directions, showing positive correlations with anxiety, fear, depression, and fear-avoidance and negative correlations with endurance and quality of life. The PASS-20 showed unique predictive ability and advantages over the Tampa Scale of Kinesiophobia. CONCLUSIONS: The results for the German PASS-20 support the original factor structure and provide evidence of satisfactory psychometric characteristics and usefulness in patients with low back pain.

Fear of movement/(Re)injury in low back pain: confirmatory validation of a German version of the Tampa Scale for Kinesiophobia.

BACKGROUND: The Tampa Scale for Kinesiophobia (TSK), an instrument for measuring fear of movement/(re)injury, has been confirmed as an important predictor for the persistence of pain-related disability. The aims of this study were to evaluate the psychometric properties of a German version of the TSK (TSK-GV), examining aspects of content validity with special focus on fear-avoidance and endurance, and to confirm criterion-related validity in patients with low back pain (LBP). METHODS: A total of 191 patients with LBP were included in this study. Several models with different factor structures from published studies were compared in a confirmatory factor analysis. Internal consistencies of the TSK-GV and its subscales were examined, and correlations with related self-report measures were calculated. RESULTS: The internal consistency of the TSK-GV was α = 0.73. A two-factor model with 11 items was found to be the best fit for our data. The two factors were labelled Somatic Focus (SF) and Activity Avoidance (AA). The total score, SF and AA revealed moderate to high correlations with other fear-avoidance variables. CONCLUSIONS: The TSK-GV is a reliable and valid measure for assessing the fear of movement/(re)injury.

Treatment Expectations-You Get What You Expect-and Depression Plays a Role.

Positive treatment expectations demonstrably shape treatment outcomes regarding pain and disability in patients with chronic low back pain. However, knowledge about positive and negative treatment expectations as putative predictors of interindividual variability in treatment outcomes is sparse, and the role of other psychological variables of interest, especially of depression as a known predictor of long-term disability, is lacking. We present results of the first prospective study considering expectations in concert with depression in a sample of 200 patients with chronic low back pain undergoing an inpatient interdisciplinary multimodal pain therapy. We analyzed the characteristics of pain and disability, treatment expectation, and depression assessed at the beginning (T0), at the end of (T1), and at 3-month follow-up (T2) of interdisciplinary multimodal pain therapy. Treatment expectations did emerge as a significant predictor of changes in pain intensity and disability, respectively, showing that positive expectations were associated with better treatment outcomes. Mediation analyses revealed a partially mediating effect of treatment expectations on the relation between depression and pain outcomes. PERSPECTIVE: These results expand knowledge regarding the role of treatment expectations in individual treatment outcome trajectories in chronic pain patients, paving the way for much-needed efforts toward optimizing patient expectations and personalized approaches in clinical settings.

The role of spontaneous vs. experimentally induced attentional strategies for the pain response to a single bout of exercise in healthy individuals.

OBJECTIVES: Exercise-induced pain and exercise-induced hypoalgesia (EIH) are well described phenomena involving physiological and cognitive mechanisms. Two experiments explored whether spontaneous and instructed mindful monitoring (MM) were associated with reduced exercise-induced pain and unpleasantness, and increased EIH compared with spontaneous and instructed thought suppression (TS) in pain-free individuals. METHODS: Eighty pain-free individuals participated in one of two randomized crossover experiments. Pressure pain thresholds (PPTs) were assessed at the leg, back and hand before and after 15 min of moderate-to-high intensity bicycling and a non-exercise control condition. Exercise-induced pain and unpleasantness were rated after bicycling. In experiment 1 (n=40), spontaneous attentional strategies were assessed with questionnaires. In experiment 2, participants (n=40) were randomly allocated to use either a TS or MM strategy during bicycling. RESULTS: In experiment 1, the change in PPTs was significantly larger after exercise compared with quiet rest (p<0.05). Higher spontaneous MM was associated with less exercise-induced unpleasantness (r=-0.41, p<0.001), whereas higher spontaneous TS was associated with higher ratings of exercise-induced unpleasantness (r=0.35, p<0.05), but not with pain intensity or EIH. In experiment 2, EIH at the back was increased in participants using instructed TS compared with participants using instructed MM (p<0.05). CONCLUSIONS: These findings suggest that spontaneous and presumably habitual (or dispositional) attentional strategies may primarily affect cognitive-evaluative aspects of exercise, such as feelings of exercise-induced unpleasantness. MM was related to less unpleasantness, whereas TS was related to higher unpleasantness. In terms of brief experimentally-induced instructions, TS seems to have an impact on physiological aspects of EIH; however, these preliminary findings need further research.

Do the WHO-ICF personal factors "age" and "sex" impact limited activity and restricted participation category profiles differently between younger and older women and men in multimodal chronic back pain rehabilitation?

PURPOSE: To investigate if the International Classification of Functioning and Health (ICF) context factors "age" and "sex" would impact the disablement and respective improvement with rehabilitation defined with the ICF core set for chronic low back pain (cLBP). Furthermore, associations between limitations/restrictions and measures of body function or quality of life were of interest. MATERIALS AND METHODS: One thousand five hundred and twelve employed cLBP patients who completed 6 months of outpatient rehabilitation and for whom complete assessments were available before and after rehabilitation. Rehabilitation comprised of progressive resistance training, psychological counseling, and educational sessions. Main outcome measures were the ICF-activity/participation core categories automatically predicted from random forests and utilizing information from the Roland Morris Disability Questionnaire and Pain Disability Index. RESULTS: Generalized linear-mixed models revealed that upon completion of rehabilitation the presence of a limitation within the ICF activity "walking" significantly decreased with significant between-group differences. The category "doing housework" demonstrated gender-specific differences, and both gender- and age-specific differences were observed for work-related participation categories. There were no meaningful associations between ICF limitation/restriction categories and body function measures (point-biserial/Spearman's correlations). CONCLUSIONS: The personal factors "age" and "sex" impact some ICF limitation/restriction categories in cLBP; appropriately addressing these personal features could further improve phase III rehabilitation outcome.Implications for rehabilitationConsistent with calls to explore the age and sex/gender influence on health and disease, little is known how these factors affect the disablement of individuals with chronic back pain.The factors "age" and "sex" drive differences in some categories within the ICF activity/restriction categories.If age- and gender-specific features in activities and participation are not appropriately addressed through interventions, rehabilitation outcome may remain suboptimal in cLBP.

Cortisol awakening response and pain-related fear-avoidance versus endurance in patients six months after lumbar disc surgery.

Recent research indicates that stress-induced, prolonged deviations in basal adrenocortical activity might contribute to ongoing/recurrent pain following lumbar disc surgery. Further, fear-avoidance and endurance responses to pain (FAR and ER) are regarded as important risk factors for pain after surgery. In patients with non-specific low back pain, FAR appear to possibly increase pain-related arousal, whereas ER may have an arousal-lowering effect, indicated by adrenocortical activity. The current study explores the relationship between basal adrenocortical activity and FAR and ER. Thirty-six patients 6 months after lumbar disc surgery participated. Basal adrenocortical activity was assessed through the cortisol awakening response (CAR), using salivary samples collected on two consecutive days. FAR and ER were estimated using questionnaires. While the ER variables pain-persistence behavior and positive mood despite pain showed negative associations with the CAR, the FAR variables fear-avoidance beliefs and avoidance of social activity were positively correlated with it. Additionally, higher CAR levels were found in patients with high versus patients with low fear-avoidance beliefs and, conversely, in patients with low versus high positive mood and pain persistence. These results indicate that FAR may increase the individuals' level of pain-related stress among patients after disc surgery, while ER may lower it.

Comparing the Effects of Thought Suppression and Focused Distraction on Pain-Related Attentional Biases in Men and Women.

Increasing attentional focus away from pain can affect pain experience, suggesting that cognitive strategies that move attentional allocation may be a moderator of pain. In a pre-post-design, the present study examined the effects of 2 cognitive strategies used in pain contexts, thought suppression and focused distraction, on subsequent pain-related attention. Thought suppression was hypothesized to increase pain-related attention, whereas focused distraction was expected to reduce it. Influences of both anxiety and sex were also considered, as secondary questions. 139 (86 women, 53 men) healthy, pain-free participants were randomly assigned to use either thought suppression or focused distraction during a mild cold pressor test (CPT). Pain-related attention was examined using a dot-probe and an attentional blink task, pre-and post-CPT. Questionnaires about relevant cognitive and emotional aspects, demographics, and pain were completed. Results showed no difference in the effect of the 2 pain inhibition strategies on pain-related attention. The hypothesized rebound effect in thought suppression on pain-related attention did not emerge. However, thought suppression showed a short-term benefit in comparison to focused distraction regarding reported pain and perceived threat during the cold pressor test. Few sex differences were found. Thus, the cognitive strategies affected pain outcomes, but did not influence pain-related attention. PERSPECTIVE: Cognitive strategies could help with pain through changing attention allocation. In this study, the effects of the 2 cognitive strategies thought suppression and focused distraction on pain-related attention in men and women were examined. Elucidating mechanisms that lie behind pain strategies that focus on changing attention may help improve treatments.

Pain and executive function: no association between remote exercise-induced hypoalgesia and cognitive inhibition in pain-free participants.

OBJECTIVES: Cognitive inhibition, which denotes the ability to suppress predominant or automatic responses, has been associated with lower pain sensitivity and larger conditioned pain modulation in humans. Studies exploring the association between cognitive inhibition and other pain inhibitory phenomena, like exercise-induced hypoalgesia (EIH), are scarce. The primary aim was to explore the association between cognitive inhibition and EIH at exercising (local) and non-exercising (remote) muscles after isometric exercise. The secondary aim was to explore the association between cognitive inhibition and pressure pain sensitivity. METHODS: Sixty-six pain-free participants (28.3 ± 8.9 years old, 34 women) completed two cognitive inhibition tasks (stop-signal task and Stroop Colour-Word task), a 3-min isometric wall squat exercise, and a quiet rest control condition with pre- and post-assessments of manual pressure pain thresholds at a local (thigh) and a remote site (shoulder). In addition, cuff pressure pain thresholds, pain tolerance and temporal summation of pain were assessed at baseline. RESULTS: No association was found between remote EIH and cognitive inhibition (Stroop interference score: r=0.12, [-0.15; 0.37], p=0.405, BF01=6.70; stop-signal reaction time: r=-0.08, [-0.32; 0.17], p=0.524, BF01=8.32). Unexpectedly, individuals with worse performance on the Stroop task, as indicated by a higher Stroop interference score, showed higher local EIH (r=0.33; [0.10; 0.53], p=0.007, BF01=0.29). No associations were observed between pain sensitivity and any of the cognitive inhibition performance parameters. CONCLUSIONS: The present findings do not support previous evidence on positive associations between exercise-induced hypoalgesia and cognitive inhibition, as well as baseline pain sensitivity and cognitive inhibition.

Central mechanisms during fatiguing muscle exercise in muscular dystrophy and fibromyalgia syndrome: a study with transcranial magnetic stimulation.

INTRODUCTION: The aim of this study was to apply paired-pulse transcranial magnetic stimulation (TMS) to assess intracortical inhibition (ICI) during fatiguing muscle exercise in healthy humans and patients with muscular dystrophy (MD) and fibromyalgia syndrome (FMS) to obtain insight into differential central mechanisms. METHODS: We studied 23 patients with MD, 16 patients with FMS, and 23 healthy controls. All participants performed a fatiguing motor task. TMS recordings were taken pre-exercise, immediately post-exercise, and 40 minutes post-exercise. RESULTS: ICI was already reduced pre-exercise in MD and FMS, whereas ICI decreased significantly during fatiguing muscle exercise only in healthy subjects. DISCUSSION: Reduced baseline ICI in patients might prevent further utilization of this presumably compensatory mechanism during fatiguing muscle exercise. Although reduced baseline to be ICI in MD can be explained as compensatory due to peripheral weakness, in FMS reduced ICI must be considered an indicator of primary central disinhibition.