1
|
Provencher B, Northon S, Piché M. Segmental Chiropractic Spinal Manipulation Does not Reduce Pain Amplification and the Associated Pain-Related Brain Activity in a Capsaicin-Heat Pain Model. FRONTIERS IN PAIN RESEARCH 2021; 2:733727. [PMID: 35295444 PMCID: PMC8915690 DOI: 10.3389/fpain.2021.733727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/11/2021] [Indexed: 11/13/2022] Open
Abstract
Musculoskeletal injuries lead to sensitization of nociceptors and primary hyperalgesia (hypersensitivity to painful stimuli). This occurs with back injuries, which are associated with acute pain and increased pain sensitivity at the site of injury. In some cases, back pain persists and leads to central sensitization and chronic pain. Thus, reducing primary hyperalgesia to prevent central sensitization may limit the transition from acute to chronic back pain. It has been shown that spinal manipulation (SM) reduces experimental and clinical pain, but the effect of SM on primary hyperalgesia and hypersensitivity to painful stimuli remains unclear. The goal of the present study was to investigate the effect of SM on pain hypersensitivity using a capsaicin-heat pain model. Laser stimulation was used to evoke heat pain and the associated brain activity, which were measured to assess their modulation by SM. Eighty healthy participants were recruited and randomly assigned to one of the four experimental groups: inert cream and no intervention; capsaicin cream and no intervention; capsaicin cream and SM at T7; capsaicin cream and placebo. Inert or capsaicin cream (1%) was applied to the T9 area. SM or placebo were performed 25 min after cream application. A series of laser stimuli were delivered on the area of cream application (1) before cream application, (2) after cream application but before SM or placebo, and (3) after SM or placebo. Capsaicin cream induced a significant increase in laser pain (p < 0.001) and laser-evoked potential amplitude (p < 0.001). However, SM did not decrease the amplification of laser pain or laser-evoked potentials by capsaicin. These results indicate that segmental SM does not reduce pain hypersensitivity and the associated pain-related brain activity in a capsaicin-heat pain model.
Collapse
Affiliation(s)
- Benjamin Provencher
- Pain Neurophysiology Lab, Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - Stéphane Northon
- Pain Neurophysiology Lab, Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - Mathieu Piché
- Pain Neurophysiology Lab, Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| |
Collapse
|
2
|
Gevers-Montoro C, Provencher B, Northon S, Stedile-Lovatel JP, Ortega de Mues A, Piché M. Chiropractic Spinal Manipulation Prevents Secondary Hyperalgesia Induced by Topical Capsaicin in Healthy Individuals. FRONTIERS IN PAIN RESEARCH 2021; 2:702429. [PMID: 35295504 PMCID: PMC8915757 DOI: 10.3389/fpain.2021.702429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/18/2021] [Indexed: 12/28/2022] Open
Abstract
Background and Aims: Spinal manipulation (SM) is currently recommended for the management of back pain. Experimental studies indicate that the hypoalgesic mechanisms of SM may rely on inhibition of segmental processes related to temporal summation of pain and, possibly, on central sensitization, although this remains unclear. The aim of this study was to determine whether experimental back pain, secondary hyperalgesia, and pain-related brain activity induced by capsaicin are decreased by segmental SM. Methods: Seventy-three healthy volunteers were randomly allocated to one of four experimental groups: SM at T5 vertebral level (segmental), SM at T9 vertebral level (heterosegmental), placebo intervention at T5 vertebral level, or no intervention. Topical capsaicin was applied to the area of T5 vertebra for 40 min. After 20 min, the interventions were administered. Pressure pain thresholds (PPTs) were assessed outside the area of capsaicin application at 0 and 40 min to examine secondary hyperalgesia. Capsaicin pain intensity and unpleasantness were reported every 4 min. Frontal high-gamma oscillations were also measured with electroencephalography. Results: Pain ratings and brain activity were not significantly different between groups over time (p > 0.5). However, PPTs were significantly decreased in the placebo and control groups (p < 0.01), indicative of secondary hyperalgesia, while no hyperalgesia was observed for groups receiving SM (p = 1.0). This effect was independent of expectations and greater than placebo for segmental (p < 0.01) but not heterosegmental SM (p = 1.0). Conclusions: These results indicate that segmental SM can prevent secondary hyperalgesia, independently of expectations. This has implications for the management of back pain, particularly when central sensitization is involved.
Collapse
Affiliation(s)
- Carlos Gevers-Montoro
- Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- Madrid College of Chiropractic, RCU Maria Cristina, Madrid, Spain
| | - Benjamin Provencher
- Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - Stéphane Northon
- Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | | | | | - Mathieu Piché
- Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| |
Collapse
|
3
|
Provencher B, Northon S, Gevers Montoro C, O'Shaughnessy J, Piché M. Effects of chiropractic spinal manipulation on laser-evoked pain and brain activity. J Physiol Sci 2021; 71:20. [PMID: 34167458 PMCID: PMC10717656 DOI: 10.1186/s12576-021-00804-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 06/15/2021] [Indexed: 12/28/2022]
Abstract
The aim of this study was to examine the mechanisms underlying hypoalgesia induced by spinal manipulation (SM). Eighty-two healthy volunteers were assigned to one of the four intervention groups: no intervention, SM at T4 (homosegmental to pain), SM at T8 (heterosegmental to pain) or light mechanical stimulus at T4 (placebo). Eighty laser stimuli were applied on back skin at T4 to evoke pain and brain activity related to Aδ- and C-fibers activation. The intervention was performed after 40 stimuli. Laser pain was decreased by SM at T4 (p = 0.028) but not T8 (p = 0.13), compared with placebo. However, brain activity related to Aδ-fibers activation was not significantly modulated (all p > 0.05), while C-fiber activity could not be measured reliably. This indicates that SM produces segmental hypoalgesia through inhibition of nociceptive processes that are independent of Aδ fibers. It remains to be clarified whether the effect is mediated by the inhibition of C-fiber activity.
Collapse
Affiliation(s)
- Benjamin Provencher
- Department of Anatomy, Université du Québec à Trois-Rivières, 3351 boul. des Forges, C.P. 500, Trois-Rivières, QC, G9A 5H7, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
| | - Stéphane Northon
- Department of Anatomy, Université du Québec à Trois-Rivières, 3351 boul. des Forges, C.P. 500, Trois-Rivières, QC, G9A 5H7, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
| | - Carlos Gevers Montoro
- Department of Anatomy, Université du Québec à Trois-Rivières, 3351 boul. des Forges, C.P. 500, Trois-Rivières, QC, G9A 5H7, Canada
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
- Madrid College of Chiropractic, Madrid, Spain
| | - Julie O'Shaughnessy
- Department of Chiropractic, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
| | - Mathieu Piché
- Department of Anatomy, Université du Québec à Trois-Rivières, 3351 boul. des Forges, C.P. 500, Trois-Rivières, QC, G9A 5H7, Canada.
- CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada.
| |
Collapse
|
4
|
Farschtschi SC, Mainka T, Glatzel M, Hannekum AL, Hauck M, Gelderblom M, Hagel C, Friedrich RE, Schuhmann MU, Schulz A, Morrison H, Kehrer-Sawatzki H, Luhmann J, Gerloff C, Bendszus M, Bäumer P, Mautner VF. C-Fiber Loss as a Possible Cause of Neuropathic Pain in Schwannomatosis. Int J Mol Sci 2020; 21:ijms21103569. [PMID: 32443592 PMCID: PMC7278954 DOI: 10.3390/ijms21103569] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/09/2020] [Accepted: 05/15/2020] [Indexed: 01/22/2023] Open
Abstract
Schwannomatosis is the third form of neurofibromatosis and characterized by the occurrence of multiple schwannomas. The most prominent symptom is chronic pain. We aimed to test whether pain in schwannomatosis might be caused by small-fiber neuropathy. Twenty patients with schwannomatosis underwent neurological examination and nerve conduction studies. Levels of pain perception as well as anxiety and depression were assessed by established questionnaires. Quantitative sensory testing (QST) and laser-evoked potentials (LEP) were performed on patients and controls. Whole-body magnetic resonance imaging (wbMRI) and magnetic resonance neurography (MRN) were performed to quantify tumors and fascicular nerve lesions; skin biopsies were performed to determine intra-epidermal nerve fiber density (IENFD). All patients suffered from chronic pain without further neurological deficits. The questionnaires indicated neuropathic symptoms with significant impact on quality of life. Peripheral nerve tumors were detected in all patients by wbMRI. MRN showed additional multiple fascicular nerve lesions in 16/18 patients. LEP showed significant faster latencies compared to normal controls. Finally, IENFD was significantly reduced in 13/14 patients. Our study therefore indicates the presence of small-fiber neuropathy, predominantly of unmyelinated C-fibers. Fascicular nerve lesions are characteristic disease features that are associated with faster LEP latencies and decreased IENFD. Together these methods may facilitate differential diagnosis of schwannomatosis.
Collapse
Affiliation(s)
- Said C. Farschtschi
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
- Correspondence: ; Tel.: +49(0)407410-53869
| | - Tina Mainka
- Department of Neurology, Charité University Medicine, 10117 Berlin, Germany;
- Berlin Institute of Health, 10178 Berlin, Germany
| | - Markus Glatzel
- Department of Neuropathology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (M.G.); (C.H.)
| | - Anna-Lena Hannekum
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
| | - Michael Hauck
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
- Department of Neurophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Mathias Gelderblom
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
| | - Christian Hagel
- Department of Neuropathology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (M.G.); (C.H.)
| | - Reinhard E. Friedrich
- Department of Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany;
| | - Martin U. Schuhmann
- Department of Neurosurgery, University Medical Center Tübingen, 72076 Tübingen, Germany;
| | - Alexander Schulz
- Leibniz Institute on Aging, Fritz Lipmann Institute, 07745 Jena, Germany; (A.S.); (H.M.)
- MVZ Human Genetics, 99084 Erfurt, Germany
| | - Helen Morrison
- Leibniz Institute on Aging, Fritz Lipmann Institute, 07745 Jena, Germany; (A.S.); (H.M.)
| | | | - Jan Luhmann
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
| | - Christian Gerloff
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
| | - Martin Bendszus
- Department of Neuroradiology, University Medical Center Heidelberg, 69120 Heidelberg, Germany; (M.B.); (P.B.)
| | - Philipp Bäumer
- Department of Neuroradiology, University Medical Center Heidelberg, 69120 Heidelberg, Germany; (M.B.); (P.B.)
- Department of Radiology, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Victor-Felix Mautner
- Department of Neurology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (A.-L.H.); (M.H.); (M.G.); (J.L.); (C.G.); (V.-F.M.)
| |
Collapse
|
5
|
Hüllemann P, Nerdal A, Sendel M, Dodurgali D, Forstenpointner J, Binder A, Baron R. Cold‐evoked potentials versus contact heat‐evoked potentials—Methodological considerations and clinical application. Eur J Pain 2019; 23:1209-1220. [DOI: 10.1002/ejp.1389] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 02/22/2019] [Accepted: 03/03/2019] [Indexed: 01/11/2023]
Affiliation(s)
- Philipp Hüllemann
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Annika Nerdal
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Manon Sendel
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Dilara Dodurgali
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Julia Forstenpointner
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Andreas Binder
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology University clinic Schleswig‐Holstein Kiel Germany
| |
Collapse
|
6
|
Vijayakumar V, Case M, Shirinpour S, He B. Quantifying and Characterizing Tonic Thermal Pain Across Subjects From EEG Data Using Random Forest Models. IEEE Trans Biomed Eng 2017; 64:2988-2996. [PMID: 28952933 DOI: 10.1109/tbme.2017.2756870] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Effective pain assessment and management strategies are needed to better manage pain. In addition to self-report, an objective pain assessment system can provide a more complete picture of the neurophysiological basis for pain. In this study, a robust and accurate machine learning approach is developed to quantify tonic thermal pain across healthy subjects into a maximum of ten distinct classes. METHODS A random forest model was trained to predict pain scores using time-frequency wavelet representations of independent components obtained from electroencephalography (EEG) data, and the relative importance of each frequency band to pain quantification is assessed. RESULTS The mean classification accuracy for predicting pain on an independent test subject for a range of 1-10 is 89.45%, highest among existing state of the art quantification algorithms for EEG. The gamma band is the most important to both intersubject and intrasubject classification accuracy. CONCLUSION The robustness and generalizability of the classifier are demonstrated. SIGNIFICANCE Our results demonstrate the potential of this tool to be used clinically to help us to improve chronic pain treatment and establish spectral biomarkers for future pain-related studies using EEG.
Collapse
|
7
|
Abstract
The exact mechanism underlying fibromyalgia is unknown, but increased facilitatory modulation and/or dysfunctional descending inhibitory pathway activity are posited as possible mechanisms contributing to sensitization of the central nervous system. The primary goal of this study is to identify a fibromyalgia neural circuit that can account for these abnormalities in central pain. The second goal is to gain a better understanding of the functional connectivity between the default and the executive attention network (salience network plus dorsal lateral prefrontal cortex) in fibromyalgia. We examine neural activity associated with fibromyalgia (N = 44) and compare these with healthy controls (N = 44) using resting state source localized EEG. Our data support an important role of the pregenual anterior cingulate cortex but also suggest that the degree of activation and the degree of integration between different brain areas is important. The inhibition of the connectivity between the dorsal lateral prefrontal cortex and the posterior cingulate cortex on the pain inhibitory pathway seems to be limited by decreased functional connectivity with the pregenual anterior cingulate cortex. Our data highlight the functional dynamics of brain regions integrated in brain networks in fibromyalgia patients.
Collapse
Affiliation(s)
- Sven Vanneste
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, United States of America
- * E-mail:
| | - Jan Ost
- BRAIN, Sint Augustinus Hospital Antwerp, Antwerp, Belgium
| | | | - Dirk De Ridder
- Department of Surgical Sciences, Section of Neurosurgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| |
Collapse
|
8
|
Fabrizi L, Verriotis M, Williams G, Lee A, Meek J, Olhede S, Fitzgerald M. Encoding of mechanical nociception differs in the adult and infant brain. Sci Rep 2016; 6:28642. [PMID: 27345331 PMCID: PMC4921818 DOI: 10.1038/srep28642] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/07/2016] [Indexed: 11/23/2022] Open
Abstract
Newborn human infants display robust pain behaviour and specific cortical activity following noxious skin stimulation, but it is not known whether brain processing of nociceptive information differs in infants and adults. Imaging studies have emphasised the overlap between infant and adult brain connectome architecture, but electrophysiological analysis of infant brain nociceptive networks can provide further understanding of the functional postnatal development of pain perception. Here we hypothesise that the human infant brain encodes noxious information with different neuronal patterns compared to adults. To test this we compared EEG responses to the same time-locked noxious skin lance in infants aged 0–19 days (n = 18, clinically required) and adults aged 23–48 years (n = 21). Time-frequency analysis revealed that while some features of adult nociceptive network activity are present in infants at longer latencies, including beta-gamma oscillations, infants display a distinct, long latency, noxious evoked 18-fold energy increase in the fast delta band (2–4 Hz) that is absent in adults. The differences in activity between infants and adults have a widespread topographic distribution across the brain. These data support our hypothesis and indicate important postnatal changes in the encoding of mechanical pain in the human brain.
Collapse
Affiliation(s)
- Lorenzo Fabrizi
- Department of Neuroscience, Physiology &Pharmacology, University College London, Gower Street, London WC1 E6BT, UK
| | - Madeleine Verriotis
- Department of Neuroscience, Physiology &Pharmacology, University College London, Gower Street, London WC1 E6BT, UK
| | - Gemma Williams
- Department of Neuroscience, Physiology &Pharmacology, University College London, Gower Street, London WC1 E6BT, UK
| | - Amy Lee
- Department of Neuroscience, Physiology &Pharmacology, University College London, Gower Street, London WC1 E6BT, UK
| | - Judith Meek
- Elizabeth Garrett Anderson Obstetric Wing, University College Hospital, London NW1 2BU, UK
| | - Sofia Olhede
- Department of Statistical Science, University College London, Gower Street, London WC1 E6BT, UK
| | - Maria Fitzgerald
- Department of Neuroscience, Physiology &Pharmacology, University College London, Gower Street, London WC1 E6BT, UK
| |
Collapse
|
9
|
Huishi Zhang C, Sohrabpour A, Lu Y, He B. Spectral and spatial changes of brain rhythmic activity in response to the sustained thermal pain stimulation. Hum Brain Mapp 2016; 37:2976-91. [PMID: 27167709 DOI: 10.1002/hbm.23220] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/26/2016] [Accepted: 04/07/2016] [Indexed: 01/01/2023] Open
Abstract
The aim of this study was to investigate the neurophysiological correlates of pain caused by sustained thermal stimulation. A group of 21 healthy volunteers was studied. Sixty-four channel continuous electroencephalography (EEG) was recorded while the subject received tonic thermal stimulation. Spectral changes extracted from EEG were quantified and correlated with pain scales reported by subjects, the stimulation intensity, and the time course. Network connectivity was assessed to study the changes in connectivity patterns and strengths among brain regions that have been previously implicated in pain processing. Spectrally, a global reduction in power was observed in the lower spectral range, from delta to alpha, with the most marked changes in the alpha band. Spatially, the contralateral region of the somatosensory cortex, identified using source localization, was most responsive to stimulation status. Maximal desynchrony was observed when stimulation was present. The degree of alpha power reduction was linearly correlated to the pain rating reported by the subjects. Contralateral alpha power changes appeared to be a robust correlate of pain intensity experienced by the subjects. Granger causality analysis showed changes in network level connectivity among pain-related brain regions due to high intensity of pain stimulation versus innocuous warm stimulation. These results imply the possibility of using noninvasive EEG to predict pain intensity and to study the underlying pain processing mechanism in coping with prolonged painful experiences. Once validated in a broader population, the present EEG-based approach may provide an objective measure for better pain management in clinical applications. Hum Brain Mapp 37:2976-2991, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Clara Huishi Zhang
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Abbas Sohrabpour
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Yunfeng Lu
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Bin He
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota.,Institute for Engineering in Medicine, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
10
|
Anticipation of electric shocks modulates low beta power and event-related fields during memory encoding. Neurobiol Learn Mem 2015; 123:196-204. [PMID: 26119254 DOI: 10.1016/j.nlm.2015.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 11/20/2022]
Abstract
In humans, the temporal and oscillatory dynamics of pain anticipation and its effects on long-term memory are largely unknown. Here, we investigated this open question by using a previously established behavioral paradigm in combination with magnetoencephalography (MEG). Healthy human subjects encoded a series of scene images, which was combined with cues predicting an aversive electric shock with different probabilities (0.2, 0.5 or 0.8). After encoding, memory for the studied images was tested using a remember/know recognition task. Behaviorally, pain anticipation did not modulate recollection-based recognition memory per se, but interacted with the perceived unpleasantness of the electric shock [visual analogue scale rating from 1 (not unpleasant) to 10 (highly unpleasant)]. More precisely, the relationship between pain anticipation and recollection followed an inverted u-shaped function the more unpleasant the shocks were rated by a subject. At the physiological level, this quadratic effect was mimicked in the event-related magnetic fields associated with successful memory formation ('DM-effect') ∼450ms after image onset at left frontal sensors. Importantly, across all subjects, shock anticipation modulated oscillatory power in the low beta frequency range (13-20Hz) in a linear fashion at left temporal sensors. Taken together, our findings indicate that beta oscillations provide a generic mechanism underlying pain anticipation; the effect on subsequent long-term memory, on the other hand, is much more variable and depends on the level of individual pain perception. As such, our findings give new and important insights into how aversive motivational states can drive memory formation.
Collapse
|
11
|
Gram M, Graversen C, Nielsen AK, Arendt-Nielsen T, Mørch CD, Andresen T, Drewes AM. A novel approach to pharmaco-EEG for investigating analgesics: assessment of spectral indices in single-sweep evoked brain potentials. Br J Clin Pharmacol 2014; 76:951-63. [PMID: 23521205 DOI: 10.1111/bcp.12120] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/12/2013] [Indexed: 01/29/2023] Open
Abstract
AIMS To compare results from analysis of averaged and single-sweep evoked brain potentials (EPs) by visual inspection and spectral analysis in order to identify an objective measure for the analgesic effect of buprenorphine and fentanyl. METHODS Twenty-two healthy males were included in a randomized study to assess the changes in EPs after 110 sweeps of painful electrical stimulation to the median nerve following treatment with buprenorphine, fentanyl or placebo patches. Bone pressure, cutaneous heat and electrical pain ratings were assessed. EPs and pain assessments were obtained before drug administration, 24, 48, 72 and 144 h after beginning of treatment. Features from EPs were extracted by three different approaches: (i) visual inspection of amplitude and latency of the main peaks in the average EPs, (ii) spectral distribution of the average EPs and (iii) spectral distribution of the EPs from single-sweeps. RESULTS Visual inspection revealed no difference between active treatments and placebo (all P > 0.05). Spectral distribution of the averaged potentials showed a decrease in the beta (12-32 Hz) band for fentanyl (P = 0.036), which however did not correlate with pain ratings. Spectral distribution in the single-sweep EPs revealed significant increases in the theta, alpha and beta bands for buprenorphine (all P < 0.05) as well as theta band increase for fentanyl (P = 0.05). For buprenorphine, beta band activity correlated with bone pressure and cutaneous heat pain (both P = 0.04, r = 0.90). CONCLUSION In conclusion single-sweep spectral band analysis increases the information on the response of the brain to opioids and may be used to identify the response to analgesics.
Collapse
Affiliation(s)
- Mikkel Gram
- Mech-Sense, Department of Gastroenterology & Hepatology, Aalborg University Hospital, Aalborg, Denmark; Center for Sensory-Motor Interactions (SMI), Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | | | | | | | | | | | | |
Collapse
|
12
|
Haas S, Brock C, Krogh K, Gram M, Nissen TD, Lundby L, Laurberg S, Drewes AM. Cortical evoked potentials in response to rapid balloon distension of the rectum and anal canal. Neurogastroenterol Motil 2014; 26:862-73. [PMID: 24750321 DOI: 10.1111/nmo.12341] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/11/2014] [Indexed: 02/08/2023]
Abstract
BACKGROUND Neurophysiological evaluation of anorectal sensory function is hampered by a paucity of methods. Rapid balloon distension (RBD) has been introduced to describe the cerebral response to rectal distension, but it has not successfully been applied to the anal canal. METHODS Nineteen healthy women received 30 RBDs in the rectum and the anal canal at intensities corresponding to sensory and unpleasantness thresholds, and response was recorded as cortical evoked potentials (CEPs) in 64-channels. The anal canal stimulations at unpleasantness level were repeated after 4 min to test the within-day reproducibility. CEPs were averaged, and to overcome latency variation related to jitter the spectral content of single sweeps was also computed. KEY RESULTS Repeated stimulation of the anal canal generated CEPs with similar latencies but smaller amplitudes compared to those from the rectum. Due to latency jitter, reproducibility of averaged CEPs was lower than what was found in the rectum. The most reproducible feature was N2P2 peak-to-peak amplitude with intra-class correlation coefficient (ICC) of 0.7 and coefficient of variation (CV) of 18%. Spectral content of the single sweeps showed reproducibility with ICCs for all bands >0.8 and corresponding CVs <7%. CONCLUSIONS & INFERENCES Cortical potentials evoked from the anal canal are challenged by latency jitter likely related to variability in muscle tone due to the distensions. Using single-sweep analysis, anal CEPs proved to be reproducible and should be used in future evaluation of the anal function.
Collapse
Affiliation(s)
- S Haas
- Department of Surgery, Aarhus University Hospital, Aarhus, Denmark
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Graversen C, Frøkjaer JB, Brock C, Drewes AM, Farina D. Support vector regression correlates single-sweep evoked brain potentials to gastrointestinal symptoms in diabetes mellitus patients. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2012:5242-5. [PMID: 23367111 DOI: 10.1109/embc.2012.6347176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Diabetes mellitus (DM) is a multi-factorial and complex disease causing autonomic neuropathy and gastrointestinal symptoms in some patients. The neural mechanisms behind these symptoms are poorly understood, but it is believed that both peripheral and central mechanisms are involved. To gain further knowledge of the central mechanisms, the aim of this study was to identify biomarkers for the altered brain activity in type-1 DM patients compared to healthy volunteers (HV), and to correlate the obtained biomarkers to clinical patient scores. The study included 14 DM patients and 15 HV, with brain activity recorded as multi-channel electroencephalography evoked brain potentials (EPs) elicited by painful electrical stimulations in the esophagus. The single-sweep EPs were decomposed by an optimized discrete wavelet transform (DWT), and averaged for each channel. The DWT features from the DM patients were discriminated from the HV by a support vector machine (SVM) applied in regression mode. For the optimal DWT, the discriminative features were extracted and the SVM regression value representing the overall alteration of the EP was correlated to the clinical scores. A classification performance of 86.2% (P=0.01) was obtained by applying a majority voting scheme to the 5 best performing channels. The biomarker was identified as decreased theta band activity. The regression value was correlated to symptoms reported by the patients (P=0.04). The methodology is an improvement of the present approach to study central mechanisms in diabetes mellitus, and may provide a future application for a clinical tool to optimize treatment in individual patients.
Collapse
Affiliation(s)
- C Graversen
- Mech-Sense, Department of Gastroenterology & Radiology, Aalborg Hospital, DK-9000 Aalborg, Denmark.
| | | | | | | | | |
Collapse
|
14
|
Nissen TD, Brock C, Graversen C, Coen SJ, Hultin L, Aziz Q, Lykkesfeldt J, Drewes AM. Translational aspects of rectal evoked potentials: a comparative study in rats and humans. Am J Physiol Gastrointest Liver Physiol 2013; 305:G119-28. [PMID: 23703652 PMCID: PMC3725684 DOI: 10.1152/ajpgi.00403.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Inconsistencies between species has stunted the progress of developing new analgesics. To increase the success of translating results between species, improved comparable models are required. Twelve rats received rectal balloon distensions on 2 different days separated by 24.3 (SD 24.6) days. Rectal balloon distensions were also performed in 18 humans (mean age: 34 yr; range: 21-56 yr; 12 men) on two separate occasions, separated by 9.3 (SD 5.5) days. In rats, cerebral evoked potentials (CEPs) were recorded by use of implanted skull-electrodes to distension pressure of 80 mmHg. In humans surface electrodes and individualized pressure, corresponding to pain detection threshold, were used. Comparison of morphology was assessed by wavelet analysis. Within- and between-day reproducibility was assessed in terms of latencies, amplitudes, and frequency content. In rats CEPs showed triphasic morphology. No differences in latencies, amplitudes, and power distribution were seen within or between days (all P ≥ 0.5). Peak-to-peak amplitude between the first positive and negative potential were the most reproducible characteristic within and between days (evaluated by intraclass correlation coefficients, ICC) (ICC = 0.99 and ICC = 9.98, respectively). In humans CEPs showed a triphasic morphology. No differences in latencies, amplitudes, or power distribution were seen within or between days (all P ≥ 0.2). Latency to the second negative potential (ICC = 0.98) and the second positive potential (ICC = 0.95) was the most reproducible characteristic within and between days. A unique and reliable translational platform was established assessing visceral sensitivity in rats and humans, which may improve the translational process of developing new drugs targeting visceral pain.
Collapse
Affiliation(s)
- Thomas Dahl Nissen
- 1Section of Biomedicine, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; ,2Biomedical Research Laboratory, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark; ,3Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark;
| | - Christina Brock
- 3Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark;
| | - Carina Graversen
- 4Mech-Sense, Department of Radiology, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark;
| | - Steven J. Coen
- 5Kings College London, Institute of Psychiatry, Department of Neuroimaging, London, United Kingdom;
| | - Leif Hultin
- 6Bioscience, AstraZeneca R&D, Mölndal, Sweden;
| | - Qasim Aziz
- 7Centre for Digestive Diseases, Blizard Institute, The Wingate Neurogastroenterology Group, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom; and
| | - Jens Lykkesfeldt
- 1Section of Biomedicine, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark;
| | - Asbjørn Mohr Drewes
- 8Center for Sensory-Motor Interactions, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| |
Collapse
|
15
|
Fabrizi L, Williams G, Lee A, Meek J, Slater R, Olhede S, Fitzgerald M. Cortical activity evoked by an acute painful tissue-damaging stimulus in healthy adult volunteers. J Neurophysiol 2013; 109:2393-403. [PMID: 23427303 PMCID: PMC3652217 DOI: 10.1152/jn.00990.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 02/18/2013] [Indexed: 12/25/2022] Open
Abstract
Everyday painful experiences are usually single events accompanied by tissue damage, and yet most experimental studies of cutaneous nociceptive processing in the brain use repeated laser, thermal, or electrical stimulations that do not damage the skin. In this study the nociceptive activity in the brain evoked by tissue-damaging skin lance was analyzed with electroencephalography (EEG) in 20 healthy adult volunteers (13 men and 7 women) aged 21-40 yr. Time-frequency analysis of the evoked activity revealed a distinct late event-related vertex potential (lance event-related potential, LERP) at 100-300 ms consisting of a phase-locked energy increase between 1 and 20 Hz (delta-beta bands). A pairwise comparison between lance and sham control stimulation also revealed a period of ultralate stronger desynchronization after lance in the delta band (1-5 Hz). Skin application of mustard oil before lancing, which sensitizes a subpopulation of nociceptors expressing the cation channel TRPA1, did not affect the ultralate desynchronization but reduced the phase-locked energy increase in delta and beta bands, suggesting a central interaction between different modalities of nociceptive inputs. Verbal descriptor screening of individual pain experience revealed that lance pain is predominantly due to Aδ fiber activation, but when individuals describe lances as C fiber mediated, an ultralate delta band event-related desynchronization occurs in the brain-evoked activity. We conclude that pain evoked by acute tissue damage is associated with distinct Aδ and C fiber-mediated patterns of synchronization and desynchronization of EEG oscillations in the brain.
Collapse
Affiliation(s)
- Lorenzo Fabrizi
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom.
| | | | | | | | | | | | | |
Collapse
|
16
|
Pomper U, Höfle M, Hauck M, Kathmann N, Engel AK, Senkowski D. Crossmodal bias of visual input on pain perception and pain-induced beta activity. Neuroimage 2012; 66:469-78. [PMID: 23110881 DOI: 10.1016/j.neuroimage.2012.10.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 10/02/2012] [Accepted: 10/04/2012] [Indexed: 12/23/2022] Open
Abstract
In our environment, acute pain is often accompanied by input from other sensory modalities, like visual stimuli, which can facilitate pain processing. To date, it is not well understood how these inputs influence the perception and processing of pain. Previous studies on integrative processing between sensory modalities other than pain have shown that multisensory response gains are strongest when the constituent unimodal stimuli are minimally effective in evoking responses. This finding has been termed the principle of inverse effectiveness (IE). In this high-density electroencephalography study, we investigated the influence of Gabor patches of low and high contrast levels on the perception and processing of spatially and temporally aligned painful electrical stimuli of low and high intensities. Subjective pain ratings, event-related potentials (ERPs) and oscillatory responses served as dependent measures. In line with the principle of IE, stronger crossmodal biasing effects of visual input on subjective pain ratings were found for low compared to high intensity painful stimuli. This effect was paralleled by stronger bimodal interactions in right-central ERPs (150-200ms) for low compared to high intensity pain stimuli. Moreover, an enhanced suppression of medio-central beta-band activity (12-24Hz, 200-400ms) was found for low compared to high intensity pain stimuli. Our findings possibly reflect a facilitation of stimulus processing that serves to enhance response readiness of the sensorimotor system following painful stimulation. Taken together, our study demonstrates that multisensory processing between visual and painful stimuli follows the principle of IE and suggests a role for beta-band oscillations in the crossmodal modulation of pain.
Collapse
Affiliation(s)
- Ulrich Pomper
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Psychiatry and Psychotherapy, Charité University Medicine Berlin, St. Hedwig Hospital, Große Hamburger Str. 5-11, 10115 Berlin, Germany.
| | - Marion Höfle
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Psychiatry and Psychotherapy, Charité University Medicine Berlin, St. Hedwig Hospital, Große Hamburger Str. 5-11, 10115 Berlin, Germany
| | - Michael Hauck
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Neurology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Norbert Kathmann
- Department of Psychology, Humboldt-Universität zu Berlin, Rudower Chaussee 18, 12489 Berlin, Germany
| | - Andreas K Engel
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Daniel Senkowski
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Psychiatry and Psychotherapy, Charité University Medicine Berlin, St. Hedwig Hospital, Große Hamburger Str. 5-11, 10115 Berlin, Germany
| |
Collapse
|
17
|
Graversen C, Brock C, Drewes AM, Farina D. Combined multivariate matching pursuit and support vector machine: a way forward to classify single-sweep evoked potentials? ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:3310-3. [PMID: 22255047 DOI: 10.1109/iembs.2011.6090898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Evoked brain potentials averaged over multiple sweeps provide a valuable objective measure of abnormal pain processing due to sensitization of the central nervous system. However, the average procedure cancel out important information regarding phase resetting and non-phase locked oscillations. Hence, assessment of the pain processing could be optimized by analyzing single-sweeps. To develop improved methods to assess single-sweeps, we applied a new approach in one healthy volunteer participating in a placebo controlled study of widespread hyperalgesia induced by perfusion of acid and capsaicin in the esophagus. The evoked potentials were recorded during electrical stimulations in the rectosigmoid colon. Features from the single-sweeps were extracted by a multivariate matching pursuit algorithm with Gabor atoms, and features were discriminated by a support vector machine with a linear kernel. The classification performance for the optimal number of atoms was 95% when discriminating the sensitization response from the placebo response, which was above change level compared to the performance when discriminating the two baseline responses (P < 0.001). The discriminative capacity was increased power in the delta, theta, and alpha frequency bands. This result corresponds to previous characteristics seen in chronic pain patients who exhibit central sensitization. The new approach to classify single-sweeps on a single subject basis might in the future prove to be a useful tool in assessing mechanisms in central sensitization, and could be applied to improve enriched enrollment of study subjects in clinical trial units.
Collapse
Affiliation(s)
- Carina Graversen
- Mech-Sense, Department of Gastroenterology & Radiology, Aalborg Hospital, DK-9100 Aalborg, Denmark.
| | | | | | | |
Collapse
|
18
|
Graversen C, Brock C, Drewes AM, Farina D. Biomarkers for visceral hypersensitivity identified by classification of electroencephalographic frequency alterations. J Neural Eng 2011; 8:056014. [DOI: 10.1088/1741-2560/8/5/056014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
19
|
Bursts of 15–30 Hz oscillations following noxious laser stimulus originate in posterior cingulate cortex. Brain Res 2010; 1317:69-79. [DOI: 10.1016/j.brainres.2009.12.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 12/02/2009] [Accepted: 12/21/2009] [Indexed: 01/20/2023]
|