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Jessen J, Höffken O, Schwenkreis P, Tegenthoff M, Özgül ÖS, Enax-Krumova E. Posttraumatic headache: pain related evoked potentials (PREP) and conditioned pain modulation (CPM) to assess the pain modulatory function. Sci Rep 2024; 14:16306. [PMID: 39009744 PMCID: PMC11251016 DOI: 10.1038/s41598-024-67288-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 07/09/2024] [Indexed: 07/17/2024] Open
Abstract
Posttraumatic headache (PTH) is common following traumatic brain injury and impacts quality of life. We investigated descending pain modulation as one possible mechanism for PTH and correlated it to clinical measures. Pain-related evoked potentials (PREP) were recorded in 26 PTH-patients and 20 controls after electrical stimulation at the right hand and forehead with concentric surface electrodes. Conditioned pain modulation (CPM) was assessed using painful cutaneous electric stimulation (PCES) on the right hand as test stimulus and immersion of the left hand into 10 °C-cold water bath as conditioning stimulus based on changes in pain intensity and in amplitudes of PCES-evoked potentials. All participants completed questionnaires assessing depression, anxiety, and pain catastrophising. PTH-patients reported significantly higher pain ratings during PREP-recording in both areas despite similar stimulus intensity at pain threshold. N1P1-amplitudes during PREP and CPM-assessment were lower in patients in both areas, but statistically significant only on the hand. Both, PREP-N1-latencies and CPM-effects (based on the N1P1-amplitudes and pain ratings) were similar in both groups. Patients showed significantly higher ratings for anxiety and depression, which did not correlate with the CPM-effect. Our results indicate generalized hyperalgesia for electrical stimuli in both hand and face in PTH. The lacking correlation between pain ratings and EEG parameters indicates different mechanisms of pain perception and nociception.
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Affiliation(s)
- Julia Jessen
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Oliver Höffken
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Peter Schwenkreis
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Martin Tegenthoff
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Özüm Simal Özgül
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Elena Enax-Krumova
- Department of Neurology, BG-University Hospital Bergmannsheil, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany.
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Horn-Hofmann C, Jablonowski L, Madden M, Kunz M, Lautenbacher S. Is conditioned pain modulation (CPM) affected by negative emotional state? Eur J Pain 2024; 28:421-433. [PMID: 37837611 DOI: 10.1002/ejp.2192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/26/2023] [Accepted: 10/03/2023] [Indexed: 10/16/2023]
Abstract
BACKGROUND Conditioned pain modulation (CPM) is an experimental paradigm, which describes the inhibition of responses to a noxious or strong-innocuous stimulus, the test stimulus (TS), by the additional application of a second noxious or strong-innocuous stimulus, the conditioning stimulus (CS). As inadequate CPM efficiency has been assumed to be predisposing for clinical pain, the search for moderating factors explaining inter-individual variations in CPM is ongoing. Psychological factors have received credits in this context. However, research concerning associations between CPM and trait factors relating to negative emotions has yielded disappointing results. Yet, the influence of anxious or fearful states on CPM has not attracted much interest despite ample evidence that negative affective states enhance pain. Our study aimed at investigating the effect of fear induction by symbolic threat on CPM. METHODS Thirty-seven healthy participants completed two experimental blocks: one presenting aversive pictures showing burn wounds (high-threat block) and one presenting neutral pictures (low-threat block). Both blocks contained a CPM paradigm with contact heat as TS and hot water as CS; subjective numerical ratings as well as contact-heat evoked potentials (CHEPs) were assessed. RESULTS We detected an overall inhibitory CPM effect for CHEPs amplitudes but not for pain ratings. However, we found no evidence for a modulation of CPM by threat despite threat ratings indicating that our manipulation was successful. DISCUSSION These results suggest that heat/thermal CPM is resistant to this specific type of symbolic threat induction and further research is necessary to examine whether it is resistant to fearful states in general. SIGNIFICANCE The attempt of modulating heat conditioned pain modulation (CPM) by emotional threat (fear/anxiety state) failed. Thus, heat CPM inhibition again appeared resistant to emotional influences. Pain-related brain potentials proved to be more sensitive for CPM effects than subjective ratings.
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Affiliation(s)
| | - Lena Jablonowski
- Department of Physiological Psychology, University of Bamberg, Bamberg, Germany
| | - Melanie Madden
- Department of Physiological Psychology, University of Bamberg, Bamberg, Germany
| | - Miriam Kunz
- Medical Psychology and Sociology, University of Augsburg, Augsburg, Germany
| | - Stefan Lautenbacher
- Department of Physiological Psychology, University of Bamberg, Bamberg, Germany
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Jin H, Witjes B, Roy M, Baillet S, de Vos CC. Neurophysiological oscillatory markers of hypoalgesia in conditioned pain modulation. Pain Rep 2023; 8:e1096. [PMID: 37881810 PMCID: PMC10597579 DOI: 10.1097/pr9.0000000000001096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 06/27/2023] [Accepted: 07/10/2023] [Indexed: 10/27/2023] Open
Abstract
Introduction Conditioned pain modulation (CPM) is an experimental procedure that consists of an ongoing noxious stimulus attenuating the pain perception caused by another noxious stimulus. A combination of the CPM paradigm with concurrent electrophysiological recordings can establish whether an association exists between experimentally modified pain perception and modulations of neural oscillations. Objectives We aimed to characterize how CPM modifies pain perception and underlying neural oscillations. We also interrogated whether these perceptual and/or neurophysiological effects are distinct in patients affected by chronic pain. Methods We presented noxious electrical stimuli to the right ankle before, during, and after CPM induced by an ice pack placed on the left forearm. Seventeen patients with chronic pain and 17 control participants rated the electrical pain in each experimental condition. We used magnetoencephalography to examine the anatomy-specific effects of CPM on the neural oscillatory responses to the electrical pain. Results Regardless of the participant groups, CPM induced a reduction in subjective pain ratings and neural responses (beta-band [15-35 Hz] oscillations in the sensorimotor cortex) to electrical pain. Conclusion Our findings of pain-induced beta-band activity may be associated with top-down modulations of pain, as reported in other perceptual modalities. Therefore, the reduced beta-band responses during CPM may indicate changes in top-down pain modulations.
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Affiliation(s)
- Hyerang Jin
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Bart Witjes
- Centre for Pain Medicine, Erasmus University Medical Centre, Rotterdam, the Netherlands
| | - Mathieu Roy
- Department of Psychology, McGill University, Montreal, Canada
| | - Sylvain Baillet
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Cecile C. de Vos
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Centre for Pain Medicine, Erasmus University Medical Centre, Rotterdam, the Netherlands
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Eberhardt F, Enax-Krumova E, Tegenthoff M, Höffken O, Özgül ÖS. Anodal transcutaneous spinal direct current stimulation influences the amplitude of pain-related evoked potentials in healthy subjects. Sci Rep 2023; 13:20920. [PMID: 38016967 PMCID: PMC10684856 DOI: 10.1038/s41598-023-47408-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 11/13/2023] [Indexed: 11/30/2023] Open
Abstract
It has already been described that transcutaneous spinal direct current stimulation (tsDCS) can selectively influence nociceptive evoked potentials. This study is the first aiming to prove an influence of tsDCS on pain-related evoked potentials (PREP) using concentric surface electrodes (CE), whose nociceptive specificity is still under discussion. 28 healthy subjects participated in this sham-controlled, double-blind cross-over study. All subjects underwent one session of anodal and one session of sham low-thoracic tsDCS. Before and after the intervention, PREP using CE, PREP-induced pain perception and somatosensory evoked potentials (SEP) were assessed on the right upper and lower limb. We found a decrease in PREP amplitude at the lower limb after sham stimulation, but not after anodal tsDCS, while SEP remained unchanged under all studied conditions. There was no difference between the effects of anodal tsDCS and sham stimulation on the studied parameters assessed at the upper limb. PREP-induced pain of the upper and lower limb increased after anodal tsDCS. The ability of influencing PREP using a CE at the spinal level in contrast to SEP suggests that PREP using CE follows the spinothalamic pathway and supports the assumption that it is specifically nociceptive. However, while mainly inhibitory effects on nociceptive stimuli have already been described, our results rather suggest that anodal tsDCS has a sensitizing effect. This may indicate that the mechanisms underlying the elicitation of PREP with CE are not the same as for the other nociceptive evoked potentials. The effects on the processing of different types of painful stimuli should be directly compared in future studies.
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Affiliation(s)
- Frederic Eberhardt
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany.
| | - Elena Enax-Krumova
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Martin Tegenthoff
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Oliver Höffken
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - Özüm Simal Özgül
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
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Adamczyk WM, Szikszay TM, Nahman-Averbuch H, Skalski J, Nastaj J, Gouverneur P, Luedtke K. To Calibrate or not to Calibrate? A Methodological Dilemma in Experimental Pain Research. THE JOURNAL OF PAIN 2022; 23:1823-1832. [PMID: 35918020 DOI: 10.1016/j.jpain.2022.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/24/2022] [Accepted: 07/20/2022] [Indexed: 05/23/2023]
Abstract
To calibrate or not to calibrate? This question is raised by almost everyone designing an experimental pain study with supra-threshold stimulation. The dilemma is whether to individualize stimulus intensity to the pain threshold / supra-threshold pain level of each participant or whether to provide the noxious stimulus at a fixed intensity so that everyone receives the identical input. Each approach has unique pros and cons which need to be considered to i) accurately design an experiment, ii) enhance statistical inference in the given data and, iii) reduce bias and the influence of confounding factors in the individual study e.g., body composition, differences in energy absorption and previous experience. Individualization requires calibration, a procedure already irritating the nociceptive system but allowing to match the pain level across individuals. It leads to a higher variability of the stimulus intensity, thereby influencing the encoding of "noxiousness" by the central nervous system. Results might be less influenced by statistical phenomena such as ceiling/floor effects and the approach does not seem to rise ethical concerns. On the other hand, applying a fixed (standardized) intensity reduces the problem of intensity encoding leading to a large between-subjects variability in pain responses. Fixed stimulation intensities do not require pre-exposure. It can be proposed that one method is not preferable over another, however the choice depends on the study aim and the desired level of external validity. This paper discusses considerations for choosing the optimal approach for experimental pain studies and provides recommendations for different study designs. PERSPECTIVE: To calibrate pain or not? This dilemma is related to almost every experimental pain research. The decision is a trade-off between statistical power and greater control of stimulus encoding. The article decomposes both approaches and presents the pros and cons of either approach supported by data and simulation experiment.
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Affiliation(s)
- Waclaw M Adamczyk
- Laboratory of Pain Research, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland; Institute of Health Sciences, Department of Physiotherapy, Pain & Exercise Research Luebeck (P.E.R.L.), University of Lübeck, Lübeck, Germany.
| | - Tibor M Szikszay
- Institute of Health Sciences, Department of Physiotherapy, Pain & Exercise Research Luebeck (P.E.R.L.), University of Lübeck, Lübeck, Germany
| | - Hadas Nahman-Averbuch
- Washington University Pain Center, Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jacek Skalski
- Laboratory of Pain Research, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | - Jakub Nastaj
- Laboratory of Pain Research, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | - Philip Gouverneur
- Institute of Medical Informatics, University of Lübeck, Lübeck, Germany
| | - Kerstin Luedtke
- Institute of Health Sciences, Department of Physiotherapy, Pain & Exercise Research Luebeck (P.E.R.L.), University of Lübeck, Lübeck, Germany; Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
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Ross JM, Ozdemir RA, Lian SJ, Fried PJ, Schmitt EM, Inouye SK, Pascual-Leone A, Shafi MM. A structured ICA-based process for removing auditory evoked potentials. Sci Rep 2022; 12:1391. [PMID: 35082350 PMCID: PMC8791940 DOI: 10.1038/s41598-022-05397-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 12/22/2021] [Indexed: 12/13/2022] Open
Abstract
Transcranial magnetic stimulation (TMS)-evoked potentials (TEPs), recorded using electroencephalography (EEG), reflect a combination of TMS-induced cortical activity and multi-sensory responses to TMS. The auditory evoked potential (AEP) is a high-amplitude sensory potential-evoked by the "click" sound produced by every TMS pulse-that can dominate the TEP and obscure observation of other neural components. The AEP is peripherally evoked and therefore should not be stimulation site specific. We address the problem of disentangling the peripherally evoked AEP of the TEP from components evoked by cortical stimulation and ask whether removal of AEP enables more accurate isolation of TEP. We hypothesized that isolation of the AEP using Independent Components Analysis (ICA) would reveal features that are stimulation site specific and unique individual features. In order to improve the effectiveness of ICA for removal of AEP from the TEP, and thus more clearly separate the transcranial-evoked and non-specific TMS-modulated potentials, we merged sham and active TMS datasets representing multiple stimulation conditions, removed the resulting AEP component, and evaluated performance across different sham protocols and clinical populations using reduction in Global and Local Mean Field Power (GMFP/LMFP) and cosine similarity analysis. We show that removing AEPs significantly reduced GMFP and LMFP in the post-stimulation TEP (14 to 400 ms), driven by time windows consistent with the N100 and P200 temporal characteristics of AEPs. Cosine similarity analysis supports that removing AEPs reduces TEP similarity between subjects and reduces TEP similarity between stimulation conditions. Similarity is reduced most in a mid-latency window consistent with the N100 time-course, but nevertheless remains high in this time window. Residual TEP in this window has a time-course and topography unique from AEPs, which follow-up exploratory analyses suggest could be a modulation in the alpha band that is not stimulation site specific but is unique to individual subject. We show, using two datasets and two implementations of sham, evidence in cortical topography, TEP time-course, GMFP/LMFP and cosine similarity analyses that this procedure is effective and conservative in removing the AEP from TEP, and may thus better isolate TMS-evoked activity. We show TEP remaining in early, mid and late latencies. The early response is site and subject specific. Later response may be consistent with TMS-modulated alpha activity that is not site specific but is unique to the individual. TEP remaining after removal of AEP is unique and can provide insight into TMS-evoked potentials and other modulated oscillatory dynamics.
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Affiliation(s)
- Jessica M Ross
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, KS-423, Boston, MA, USA.
- Department of Neurology, Harvard Medical School, Boston, MA, USA.
| | - Recep A Ozdemir
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, KS-423, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Shu Jing Lian
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, KS-423, Boston, MA, USA
| | - Peter J Fried
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, KS-423, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Eva M Schmitt
- Hinda and Arthur Marcus Institute for Aging Research, and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, USA
| | - Sharon K Inouye
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- Hinda and Arthur Marcus Institute for Aging Research, and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, USA
| | - Alvaro Pascual-Leone
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Hinda and Arthur Marcus Institute for Aging Research, and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, USA
- Guttmann Brain Health Institute, Institut Guttmann, Institut Universitari de Neurorehabilitació adscrit a la UAB, Badalona, Barcelona, Spain
| | - Mouhsin M Shafi
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, KS-423, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
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7
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Ramaswamy S, Wodehouse T. Conditioned pain modulation-A comprehensive review. Neurophysiol Clin 2020; 51:197-208. [PMID: 33334645 DOI: 10.1016/j.neucli.2020.11.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 11/25/2020] [Accepted: 11/28/2020] [Indexed: 01/05/2023] Open
Abstract
Conditioned pain modulation (CPM) is a centrally processed measure of the net effect of the descending pain pathway. This comprises both the facilitatory as well as the inhibitory effect. In the past, CPM or similar effects have been previously described using different terminologies such as diffuse noxious inhibitory control (DNIC), heterotopic noxious conditioning stimulation (HNCS) or endogenous analgesia (EA). A variety of patient-related factors such as age, gender, hormones, race, genetic and psychological factors have been thought to influence the CPM paradigms. CPM paradigms have also been associated with a wide range of methodological variables including the mode of application of the 'test' as well as the 'conditioning' stimuli. Despite all these variabilities, CPM seems to reliably lend itself to the pain modulation profile concept and could in future become one of the phenotypic biomarkers for pain and also a guide for mechanism-based treatment in chronic pain. Future research should focus on establishing consistent methodologies for measuring CPM and thereby enhancing the robustness of this emerging biomarker for pain.
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Affiliation(s)
- Shankar Ramaswamy
- 1St Bartholomew's Hospital, Bart's Health NHS Trust, London, EC1A 4AS, UK.
| | - Theresa Wodehouse
- 1St Bartholomew's Hospital, Bart's Health NHS Trust, London, EC1A 4AS, UK
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Do ATL, Enax-Krumova EK, Özgül Ö, Eitner LB, Heba S, Tegenthoff M, Maier C, Höffken O. Distraction by a cognitive task has a higher impact on electrophysiological measures compared with conditioned pain modulation. BMC Neurosci 2020; 21:53. [PMID: 33287715 PMCID: PMC7720448 DOI: 10.1186/s12868-020-00604-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/23/2020] [Indexed: 12/23/2022] Open
Abstract
Background Conditioned pain modulation (CPM) evaluates the effect of a painful conditioning stimulus (CS) on a painful test stimulus (TS). Using painful cutaneous electrical stimulation (PCES) as TS and painful cold water as CS, the pain relief was paralleled by a decrease in evoked potentials (PCES-EPs). We now aimed to compare the effect of CPM with cognitive distraction on PCES-induced pain and PCES-EP amplitudes. Methods PCES was performed using surface electrodes inducing a painful sensation of 60 (NRS 0–100) on one hand. In a crossover design healthy subjects (included: n = 38, analyzed: n = 23) immersed the contralateral hand into 10 °C cold water (CS) for CPM evaluation and performed the 1-back task for cognitive distraction. Before and during the CS and 1-back task, respectively, subjects rated the pain intensity of PCES and simultaneously cortical evoked potentials were recorded. Results Both CPM and cognitive distraction significantly reduced PCES-EP amplitudes (CPM: 27.6 ± 12.0 μV to 20.2 ± 9.5 μV, cognitive distraction: 30.3 ± 14.2 µV to 13.6 ± 5.2 μV, p < 0.001) and PCES-induced pain (on a 0–100 numerical rating scale: CPM: 58 ± 4 to 41.1 ± 12.3, cognitive distraction: 58.3 ± 4.4 to 38.0 ± 13.0, p < 0.001), though the changes in pain intensity and PCES-amplitude did not correlate. The changes of the PCES-EP amplitudes during cognitive distraction were more pronounced than during CPM (p = 0.001). Conclusions CPM and cognitive distraction reduced the PCES-induced pain to a similar extent. The more pronounced decrease of PCES-EP amplitudes after distraction by a cognitive task implies that both conditions might not represent the general pain modulatory capacity of individuals, but may underlie different neuronal mechanisms with the final common pathway of perceived pain reduction.
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Affiliation(s)
- A T L Do
- Department of Neurology, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - E K Enax-Krumova
- Department of Neurology, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany.
| | - Ö Özgül
- Department of Neurology, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - L B Eitner
- Department of Pain Medicine, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany.,Department of Neuropaediatrics, University Children's Hospital, Ruhr-University Bochum, Alexandrinenstraße 5, 44791, Bochum, Germany
| | - S Heba
- Department of Neurology, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | | | - C Maier
- Department of Pain Medicine, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
| | - O Höffken
- Department of Neurology, Ruhr-University Bochum, BG University Hospital Bergmannsheil gGmbH, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany
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Squintani G, Rasera A, Segatti A, Concon E, Bonetti B, Valeriani M, Tinazzi M. Conditioned pain modulation affects the N2/P2 complex but not the N1 wave: A pilot study with laser-evoked potentials. Eur J Pain 2020; 25:550-557. [PMID: 33170987 DOI: 10.1002/ejp.1693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The 'pain-inhibits-pain' effect stems from neurophysiological mechanisms involving endogenous modulatory systems termed diffuse noxious inhibitory controls (DNIC) or conditioned pain modulation (CPM). Laser-evoked potentials (LEPs) components, the N2/P2 complex, and the N1 wave, reflect the medial and lateral pain pathway, respectively: anatomically, the lateral thalamic nuclei (LT) project mainly to the somatosensory cortex (N1 generator), while the medial thalamic nuclei (MT) are bound to the limbic cortices (N2/P2 generators). METHODS We applied a CPM protocol in which the test stimulus was laser stimulation and the conditioning stimulus was a cold pressor test. LEPs recordings were obtained from 15 healthy subjects in three different conditions: baseline, during heterotopic noxious conditioning stimulation (HNCS) and post-HNCS. RESULTS We observed a significant reduction in N2/P2 amplitude during HNCS and a return to pre-test amplitude post-HNCS, whereas the N1 wave remained unchanged during and post-HNCS. CONCLUSIONS Our results indicate that CPM affects only the medial pain system. The spinothalamic tract (STT) transmits to both the LT and the MT, while the spinoreticulothalamic (SRT) projects only to the MT. The reduction in the amplitude of the N2/P2 complex and the absence of change in the N1 wave suggest that DNIC inhibition on the dorsal horn neurons affects only pain transmission via the SRT, while the neurons that give rise to the STT are not involved. The N1 wave can be a reliable neurophysiological parameter for assessment of STT function in clinical practice, as it does not seem to be influenced by CPM. SIGNIFICANCE No reports have described the effect of DNIC on lateral and medial pain pathways. We studied the N1 wave and the N2/P2 complex to detect changes during a CPM protocol. We found a reduction in the amplitude of the N2/P2 complex and no change in the N1 wave. This suggests that the DNIC inhibitory effect on dorsal horns neurons affects only pain transmission via the SRT, whereas the neurons that give rise to the STT are not involved.
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Affiliation(s)
- Giovanna Squintani
- Neurology and Neurophysiology Unit, Neuroscience Department, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Andrea Rasera
- Department of Neurological, Neuropsychological, Morphological and Motor Sciences, University of Verona, Verona, Italy
| | - Alessia Segatti
- Neurology and Neurophysiology Unit, Neuroscience Department, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Elisa Concon
- Neurology and Neurophysiology Unit, Neuroscience Department, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Bruno Bonetti
- Neurology and Neurophysiology Unit, Neuroscience Department, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | | | - Michele Tinazzi
- Department of Neurological, Neuropsychological, Morphological and Motor Sciences, University of Verona, Verona, Italy
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Painful Cutaneous Electrical Stimulation vs. Heat Pain as Test Stimuli in Conditioned Pain Modulation. Brain Sci 2020; 10:brainsci10100684. [PMID: 32998204 PMCID: PMC7599732 DOI: 10.3390/brainsci10100684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 09/24/2020] [Accepted: 09/26/2020] [Indexed: 11/30/2022] Open
Abstract
Different paradigms can assess the effect of conditioned pain modulation (CPM). The aim of the present study was to compare heat pain, as an often used test stimulus (TS), to painful cutaneous electrical stimulation (PCES), having the advantage of the additional recording of PCES-related evoked potentials. In 28 healthy subjects we applied heat and PCES at the dominant hand as test stimulus (TS) to compare the CPM-effect elicited by hand immersion into cold water (10 °C) as conditioning stimulus (CS). Subjects rated the pain intensity of TS at baseline, during and 5 min after CS application and additionally of CS, on a numerical rating scale (NRS) (0–100). The ‘early’ (during CS–before CS) and ‘late’ (after CS–before CS) CPM-effects were analyzed. Parallel to the PCES, the related evoked potentials were recorded via Cz to evaluate any changes in PCES-amplitudes. CS reduced significantly the pain intensity of both PCES and heat pain as TS. On a group level, the CPM-effect did not differ significantly between both paradigms. Both early and late CPM-effect based on PCES correlated significantly with the CS pain intensity (r = −0.630 and −0.503, respectively), whereas using heat pain the correlation was not significant. We found a significant reduction of PCES-amplitudes during CS, but this did not correlate with the PCES-induced pain intensity. Correlation with the CS painfulness (r = −0.464) did not achieve the significance level after Bonferroni correction. The extent of the CPM effects was similar in both testing paradigms at group level, despite intraindividual differences. Future studies should further elicit the exact mechanisms explaining the modality of these specific differences.
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The Association Between Conditioned Pain Modulation and Manipulation-induced Analgesia in People With Lateral Epicondylalgia. Clin J Pain 2020; 35:435-442. [PMID: 30801339 PMCID: PMC6467555 DOI: 10.1097/ajp.0000000000000696] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Conditioned pain modulation (CPM) and manipulation-induced analgesia (MIA) may activate similar neurophysiological mechanisms to mediate their analgesic effects. This study assessed the association between CPM and MIA responses in people with lateral epicondylalgia. MATERIALS AND METHODS Seventy participants with lateral epicondylalgia were assessed for CPM followed by MIA. A single assessor measured pressure pain thresholds (PPT) before, during, and after cold water immersion (10°C) of the asymptomatic hand and contralateral lateral glide (CLG) mobilization of the neck. For analyses, linear mixed models evaluated differences in CPM and MIA responses. Pearson partial correlations and regression analyses evaluated the association between CPM and MIA PPT. RESULTS There was a significant increase (CPM and MIA, P<0.001) in PPT from baseline during the interventions (CPM mean: 195.84 kPa for elbow and 201.87 kPa for wrist, MIA mean: 123.01 kPa for elbow and 126.06 kPa for wrist) and after the interventions (CPM mean: 126.06 kPa for elbow, 114.24 kPa for wrist, MIA mean: 123.50 kPa for elbow and 122.16 kPa for wrist). There were also significant moderate and positive partial linear correlations (r: 0.40 to 0.54, P<0.001) between CPM and MIA measures, controlling for baseline measures. Regression analyses showed that CPM PPT was a significant predictor of MIA PPT (P<0.001) and the models explained between 73% and 85% of the variance in MIA PPT. DISCUSSION This study showed that CPM and MIA responses were significantly correlated and that the CPM response was a significant predictor of MIA response.
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The Influence of a Positive Empathetic Interaction on Conditioned Pain Modulation and Manipulation-induced Analgesia in People With Lateral Epicondylalgia. Clin J Pain 2020; 36:411-419. [PMID: 32079999 DOI: 10.1097/ajp.0000000000000822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Conditioned pain modulation (CPM) and manipulation-induced analgesia (MIA) are 2 forms of endogenous analgesia. Many forms of analgesia can be influenced by the nature of the patient-clinician interaction. The aim of this study was to evaluate the influence of an empathetic and supportive interaction on CPM and MIA in people with lateral epicondylalgia (LE). MATERIAL AND METHODS In a double-blind, randomized, controlled trial, 68 participants with LE were assigned to 2 groups: the empathetic and neutral interaction groups. The interactions were carried out by a trained, professional role-play actor, playing the part of a research assistant. The research assistant actor spent 15 minutes before CPM and MIA assessment interacting with the participants in an empathetic or neutral manner. Immediately after the interaction, a blinded assessor measured pressure pain threshold at the symptomatic elbow and ipsilateral wrist during CPM and MIA testing. Linear mixed models were used to evaluate differences in CPM and MIA responses between the interaction groups. RESULTS There was a significant difference in Consultation and Relational Empathy scores between the groups (P<0.001), indicating that the intervention group experienced a more empathic interaction. Both groups showed a significant increase in pressure pain threshold measures, indicative of a CPM and MIA analgesic response (P<0.001), however, the analgesic responses were greater in the group that had experienced a supportive, empathetic interaction (post CPM, wrist: P<0.001; elbow: P=0.001) (post MIA wrist: P<0.001; elbow: P=0.001). DISCUSSION A single session of empathetic interaction positively influenced both CPM and MIA responses in people with LE.
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Tsedinova Y, Churuykanov M, Medvedeva L, Zagorulko O. Neurophysiological methods in examination of patients with chronic postoperative pain. ACTA ACUST UNITED AC 2020. [DOI: 10.17116/pain20201804160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Albu S, Meagher MW. Divergent effects of conditioned pain modulation on subjective pain and nociceptive-related brain activity. Exp Brain Res 2019; 237:1735-1744. [PMID: 31030281 DOI: 10.1007/s00221-019-05545-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 04/24/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND OBJECTIVES Pain is a complex experience involving both nociceptive and affective-cognitive mechanisms. The present study evaluated whether modulation of pain perception, employing a conditioned pain modulation (CPM) paradigm, is paralleled by changes in contact heat-evoked potentials (CHEPs), a brain response to nociceptive stimuli. METHODS Participants were 25 healthy, pain-free, college students (12 males, 13 females, mean age 19.24 ± 0.97 years). Twenty computer-controlled heat stimuli were delivered to the non-dominant forearm and CHEPs were recorded at Cz using a 32-channel EEG system. After each stimulus, participants rated the intensity of the heat pain using the 0-100 numerical rating scale. The latency and amplitude of N2, P2 components as well as single-sweep spectral analysis of individual CHEPs were measured offline. For CPM, participants had to submerge their dominant foot into a neutral (32 °C) or noxious (0 °C) water bath. CHEPs and heat pain ratings were recorded in 3 different conditions: without CPM, after neutral CPM (32 °C) and after noxious CPM (0 °C). RESULTS The noxious CPM induced a facilitatory pain response (p = 0.001) with an increase in heat pain following noxious CPM compared to neutral CPM (p = 0.001) and no CPM (p = 0.001). Changes in CHEPs did not differ between conditions when measured as N2-P2 peak-to-peak amplitude (p = 0.33) but the CPM significantly suppressed the CHEPs-related delta power (p = 0.03). Changes in heat pain in the noxious CPM were predicted by trait catastrophizing variables (p = 0.04). CONCLUSION The current study revealed that pain facilitatory CPM is related to suppression of CHEPs delta power which could be related to dissociation between brain responses to noxious heat and pain perception.
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Affiliation(s)
- Sergiu Albu
- Institute Guttmann, Neurorehabilitation Hospital, Camí Can Ruti s/n, Badalona, 08916, Barcelona, Spain.
| | - Mary W Meagher
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, 77843, USA
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Güven A, Batbat T. Evaluation of filters over different stimulation models in evoked potentials. Biocybern Biomed Eng 2019. [DOI: 10.1016/j.bbe.2018.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
Clinical neurophysiologic investigation of pain pathways in humans is based on specific techniques and approaches, since conventional methods of nerve conduction studies and somatosensory evoked potentials do not explore these pathways. The proposed techniques use various types of painful stimuli (thermal, laser, mechanical, or electrical) and various types of assessments (measurement of sensory thresholds, study of nerve fiber excitability, or recording of electromyographic reflexes or cortical potentials). The two main tests used in clinical practice are quantitative sensory testing and pain-related evoked potentials (PREPs). In particular, PREPs offer the possibility of an objective assessment of nociceptive pathways. Three types of PREPs can be distinguished depending on the type of stimulation used to evoke pain: laser-evoked potentials, contact heat evoked potentials, and intraepidermal electrical stimulation evoked potentials (IEEPs). These three techniques investigate both small-diameter peripheral nociceptive afferents (mainly Aδ nerve fibers) and spinothalamic tracts without theoretically being able to differentiate the level of lesion in the case of abnormal results. In routine clinical practice, PREP recording is a reliable method of investigation for objectifying the existence of a peripheral or central lesion or loss of function concerning the nociceptive pathways, but not the existence of pain. Other methods, such as nerve fiber excitability studies using microneurography, more directly reflect the activities of nociceptive axons in response to provoked pain, but without detecting or quantifying the presence of spontaneous pain. These methods are more often used in research or experimental study design. Thus, it should be kept in mind that most of the results of neurophysiologic investigation performed in clinical practice assess small fiber or spinothalamic tract lesions rather than the neuronal mechanisms directly at the origin of pain and they do not provide objective quantification of pain.
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Affiliation(s)
- Jean-Pascal Lefaucheur
- Excitabilité Nerveuse et Thérapeutique, Faculté de Médecine de Créteil, Université Paris-Est-Créteil, Hôpital Henri Mondor, Créteil, France; Service de Physiologie-Explorations Fonctionnelles, Hôpital Henri Mondor, Créteil, France.
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Fischer M, Höffken O, Özgül ÖS, Maier C. Bilaterally prolonged latencies of pain-related evoked potentials in peripheral nerve injuries. Neurosci Lett 2018; 684:78-85. [PMID: 30008381 DOI: 10.1016/j.neulet.2018.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/01/2018] [Accepted: 07/02/2018] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Cross-sectional study to test the applicability of pain-related evoked potentials (PREP) for the diagnosis of peripheral nerve injuries (PNI). INTRODUCTION Patients with generalized polyneuropathies show prolonged latencies and decreased amplitudes of PREP indicating an impairment of A-delta fibers. Although these fibers are frequently affected in PNI, it is unclear, if PREP-testing detects PNI comparable to Nerve Conduction Studies (NCS). METHODS 23 patients with PNI of one upper limb underwent bilateral PREP-testing (using concentric surface electrodes) and NCS. 41 healthy controls underwent PREP-testing only. We determined pain thresholds, N1-latencies and N1P1-amplitudes of PREP and analyzed them for group and side-to-side differences. Small-fiber function was evaluated using thermal detection thresholds of Quantitative Sensory Testing (QST). N1-latencies above a cut-off calculated by ROC-analysis were defined as abnormal in order to compare detection rates of PREP and NCS. RESULTS Patients with PNI showed bilaterally prolonged N1-latencies (ipsilateral: 167.0 ± 40.7 ms vs. 141.2 ± 20.5 ms / contralateral: 160.0 ± 41.0 ms vs. 140.2 ± 23.9 ms) without a significant side-to-side difference. Pain thresholds were increased on the affected side only (4.6 ± 5.2 mA vs. 2.4 ± 1.4 mA (controls)). N1P1-amplitudes did not differ between patients and controls. 7 (32%) patients showed prolonged N1-latencies (>176 ms) of PREP. NCS were abnormal in 16 (73%) cases. 13 (59%) patients showed thermal hypoesthesia in QST. CONCLUSION Contrary to our expectations, we found bilaterally prolonged N1-latencies and normal N1P1-amplitudes in patients with PNI. Our findings support the hypothesis of a bilateral generation of PREP and indicate that PREP are not suitable for the diagnosis of PNI.
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Affiliation(s)
- Marc Fischer
- Department of Pain Medicine, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bochum, Germany.
| | - Oliver Höffken
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bochum, Germany.
| | - Özüm Simal Özgül
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bochum, Germany.
| | - Christoph Maier
- Department of Pain Medicine, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bochum, Germany.
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Damien J, Colloca L, Bellei-Rodriguez CÉ, Marchand S. Pain Modulation: From Conditioned Pain Modulation to Placebo and Nocebo Effects in Experimental and Clinical Pain. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 139:255-296. [PMID: 30146050 DOI: 10.1016/bs.irn.2018.07.024] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Accumulating evidence reveal important applications of endogenous pain modulation assessment in healthy controls and in patients in clinical settings, as dysregulations in the balance of pain modulatory circuits may facilitate pain and promote chronification of pain. This article reviews data on pain modulation, focusing on the mechanisms and translational aspects of pain modulation from conditioned pain modulation (CPM) to placebo and nocebo effects in experimental and clinical pain. The specific roles of expectations, learning, neural and neurophysiological mechanisms of the central nervous system are briefly reviewed herein. The interaction between CPM and placebo systems in pain inhibitory pathways is highly relevant in the clinic and in randomized controlled trials yet remains to be clarified. Examples of clinical implications of CPM and its relationship to placebo and nocebo effects are provided. A greater understanding of the role of pain modulation in various pain states can help characterize the manifestation and development of chronic pain and assist in predicting the response to pain-relieving treatments. Placebo and nocebo effects, intrinsic to every treatment, can be used to develop personalized therapeutic approaches that improve clinical outcomes while limiting unwanted effects.
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Affiliation(s)
- Janie Damien
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Luana Colloca
- Department of Pain Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, United States; Departments of Psychiatry and Anesthesiology, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Carmen-Édith Bellei-Rodriguez
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Serge Marchand
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Fonds de Recherche du Québec-Santé (FRQS), Montréal, QC, Canada.
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Eitner L, Özgül Ö, Enax-Krumova E, Vollert J, Maier C, Höffken O. Conditioned pain modulation using painful cutaneous electrical stimulation or simply habituation? Eur J Pain 2018; 22:1281-1290. [DOI: 10.1002/ejp.1215] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2018] [Indexed: 01/01/2023]
Affiliation(s)
- L. Eitner
- Department of Pain Medicine; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
- Department of Neuropediatrics; Ruhr-University Bochum; University Children's Hospital; Germany
| | - Ö.S. Özgül
- Department of Neurology; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
| | - E.K. Enax-Krumova
- Department of Neurology; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
| | - J. Vollert
- Department of Pain Medicine; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
- Pain Research; Department of Surgery and Cancer; Imperial College; London UK
- Center of Biomedicine and Medical Technology Mannheim CBTM; Medical Faculty Mannheim; Heidelberg University; Germany
| | - C. Maier
- Department of Pain Medicine; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
| | - O. Höffken
- Department of Neurology; Ruhr-University Bochum; Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil gGmbH Bochum; Germany
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