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Zidda F, Lyu Y, Nees F, Radev ST, Sitges C, Montoya P, Flor H, Andoh J. Neural dynamics of pain modulation by emotional valence. Cereb Cortex 2024; 34:bhae358. [PMID: 39245849 DOI: 10.1093/cercor/bhae358] [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: 05/29/2023] [Revised: 07/10/2024] [Accepted: 08/16/2024] [Indexed: 09/10/2024] Open
Abstract
Definitions of human pain acknowledge at least two dimensions of pain, affective and sensory, described as separable and thus potentially differentially modifiable. Using electroencephalography, we investigated perceptual and neural changes of emotional pain modulation in healthy individuals. Painful electrical stimuli were applied after presentation of priming emotional pictures (negative, neutral, positive) and followed by pain intensity and unpleasantness ratings. We found that perceptual and neural event-related potential responses to painful stimulation were significantly modulated by emotional valence. Specifically, pain unpleasantness but not pain intensity ratings were increased when pain was preceded by negative compared to neutral or positive pictures. Amplitudes of N2 were higher when pain was preceded by neutral compared to negative and positive pictures, and P2 amplitudes were higher for negative compared to neutral and positive pictures. In addition, a hierarchical regression analysis revealed that P2 alone and not N2, predicted pain perception. Finally, source analysis showed the anterior cingulate cortex and the thalamus as main spatial clusters accounting for the neural changes in pain processing. These findings provide evidence for a separation of the sensory and affective dimensions of pain and open new perspectives for mechanisms of pain modulation.
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Affiliation(s)
- Francesca Zidda
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
| | - Yuanyuan Lyu
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
- School of Biomedical Engineering, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Frauke Nees
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
- Institute of Medical Psychology and Medical Sociology, University Medical Center Schleswig-Holstein, Kiel University, 24105, Kiel, Germany
| | - Stefan T Radev
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
| | - Carolina Sitges
- Department of Psychology, Research Institute of Health Sciences (IUNICS), Health Research Institute of the Balearic Islands (IdISBa), University of the Balearic Islands, 07122, Palma, Spain
| | - Pedro Montoya
- Department of Psychology, Research Institute of Health Sciences (IUNICS), Health Research Institute of the Balearic Islands (IdISBa), University of the Balearic Islands, 07122, Palma, Spain
| | - Herta Flor
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
| | - Jamila Andoh
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim / Heidelberg University, J5, Mannheim 68159, Mannheim, Germany
- Department of Psychiatry and Psychotherapy, Medical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, J5, 68159, Mannheim, Germany
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Dong WK. Modulation of multisensory nociceptive neurons in monkey cortical area 7b and behavioral correlates. J Neurophysiol 2024; 132:544-569. [PMID: 38985936 PMCID: PMC11427044 DOI: 10.1152/jn.00377.2023] [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: 10/13/2023] [Revised: 07/08/2024] [Accepted: 07/08/2024] [Indexed: 07/12/2024] Open
Abstract
Wide-range thermoreceptive neurons (WRT-EN) in monkey cortical area 7b that encoded innocuous and nocuous cutaneous thermal and threatening visuosensory stimulation with high fidelity were studied to identify their multisensory integrative response properties. Emphasis was given to characterizing the spatial and temporal effects of threatening visuosensory input on the thermal stimulus-response properties of these multisensory nociceptive neurons. Threatening visuosensory stimulation was most efficacious in modulating thermal evoked responses when presented as a downward ("looming"), spatially congruent, approaching and closely proximal target in relation to the somatosensory receptive field. Both temporal alignment and misalignment of spatially aligned threatening visual and thermal stimulation significantly increased mean discharge frequencies above those evoked by thermal stimulation alone, particularly at near noxious (43°C) and mildly noxious (45°C) temperatures. The enhanced multisensory discharge frequencies were equivalent to the discharge frequency evoked by overtly noxious thermal stimulation alone at 47°C (monkey pain tolerance threshold). A significant increase in behavioral mean escape frequency with shorter escape latency was evoked by multisensory stimulation at near noxious temperature (43°C), which was equivalent to that evoked by noxious stimulation alone (47°C). The remarkable concordance of elevating both neural discharge and escape frequency from a nonnociceptive and prepain level by near noxious thermal stimulation to a nociceptive and pain level by multisensory visual and near noxious thermal stimulation and integration is an elegantly designed defensive neural mechanism that in effect lowers both nociceptive response and pain thresholds to preemptively engage nocifensive behavior and, consequently, avert impending and actual injurious noxious thermal stimulation.NEW & NOTEWORTHY Multisensory nociceptive neurons in cortical area 7b are engaged in integration of threatening visuosensory and a wide range of innocuous and nocuous somatosensory (thermoreceptive) inputs. The enhancement of neuronal activity and escape behavior in monkey by multisensory integration is consistent and supportive of human psychophysical studies. The spatial features of visuosensory stimulation in peripersonal space in relation to somatic stimulation in personal space are critical to multisensory integration, nociception, nocifensive behavior, and pain.
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Affiliation(s)
- Willie K Dong
- Department of Anesthesiology and Pain Medicine, School of Medicine, University of Washington, Seattle, Washington, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois, United States
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Franz S, Heutehaus L, Tappe-Theodor A, Weidner N, Treede RD, Schuh-Hofer S. Noxious radiant heat evokes bi-component nociceptive withdrawal reflexes in spinal cord injured humans-A clinical tool to study neuroplastic changes of spinal neural circuits. Front Hum Neurosci 2023; 17:1141690. [PMID: 37200949 PMCID: PMC10185789 DOI: 10.3389/fnhum.2023.1141690] [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: 02/07/2023] [Accepted: 04/04/2023] [Indexed: 05/20/2023] Open
Abstract
Investigating nocifensive withdrawal reflexes as potential surrogate marker for the spinal excitation level may widen the understanding of maladaptive nociceptive processing after spinal cord injury (SCI). The aim of this prospective, explorative cross-sectional observational study was to investigate the response behavior of individuals with SCI to noxious radiant heat (laser) stimuli and to assess its relation to spasticity and neuropathic pain, two clinical consequences of spinal hyperexcitability/spinal disinhibition. Laser stimuli were applied at the sole and dorsum of the foot and below the fibula head. Corresponding reflexes were electromyography (EMG) recorded ipsilateral. Motor responses to laser stimuli were analyzed and related to clinical readouts (severity of injury/spasticity/pain), using established clinical assessment tools. Twenty-seven participants, 15 with SCI (age 18-63; 6.5 years post-injury; AIS-A through D) and 12 non-disabled controls, [non-disabled controls (NDC); age 19-63] were included. The percentage of individuals with SCI responding to stimuli (70-77%; p < 0.001), their response rates (16-21%; p < 0.05) and their reflex magnitude (p < 0.05) were significantly higher compared to NDC. SCI-related reflexes clustered in two time-windows, indicating involvement of both A-delta- and C-fibers. Spasticity was associated with facilitated reflexes in SCI (Kendall-tau-b p ≤ 0.05) and inversely associated with the occurrence/severity of neuropathic pain (Fisher's exact p < 0.05; Eta-coefficient p < 0.05). However, neuropathic pain was not related to reflex behavior. Altogether, we found a bi-component motor hyperresponsiveness of SCI to noxious heat, which correlated with spasticity, but not neuropathic pain. Laser-evoked withdrawal reflexes may become a suitable outcome parameter to explore maladaptive spinal circuitries in SCI and to assess the effect of targeted treatment strategies. Registration: https://drks.de/search/de/trial/DRKS00006779.
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Affiliation(s)
- Steffen Franz
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
- Steffen Franz,
| | - Laura Heutehaus
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Anke Tappe-Theodor
- Department of Molecular Pharmacology, Medical Faculty Heidelberg, Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Norbert Weidner
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Rolf-Detlef Treede
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany
| | - Sigrid Schuh-Hofer
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany
- Department of Neurology and Epileptology, University of Tübingen, Tübingen, Germany
- *Correspondence: Sigrid Schuh-Hofer,
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Trevarrow MP, Reelfs A, Ott LR, Penhale SH, Lew BJ, Goeller J, Wilson TW, Kurz MJ. Altered spontaneous cortical activity predicts pain perception in individuals with cerebral palsy. Brain Commun 2022; 4:fcac087. [PMID: 35441137 PMCID: PMC9014448 DOI: 10.1093/braincomms/fcac087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/13/2022] [Accepted: 03/31/2022] [Indexed: 12/04/2022] Open
Abstract
Cerebral palsy is the most common paediatric neurological disorder and results in extensive impairment to the sensorimotor system. However, these individuals also experience increased pain perception, resulting in decreased quality of life. In the present study, we utilized magnetoencephalographic brain imaging to examine whether alterations in spontaneous neural activity predict the level of pain experienced in a cohort of 38 individuals with spastic diplegic cerebral palsy and 67 neurotypical controls. Participants completed 5 min of an eyes closed resting-state paradigm while undergoing a magnetoencephalography recording. The magnetoencephalographic data were then source imaged, and the power within the delta (2–4 Hz), theta (5–7 Hz), alpha (8–12 Hz), beta (15–29 Hz), low gamma (30–59 Hz) and high gamma (60–90 Hz) frequency bands were computed. The resulting power spectral density maps were analysed vertex-wise to identify differences in spontaneous activity between groups. Our findings indicated that spontaneous cortical activity was altered in the participants with cerebral palsy in the delta, alpha, beta, low gamma and high gamma bands across the occipital, frontal and secondary somatosensory cortical areas (all pFWE < 0.05). Furthermore, we also found that the altered beta band spontaneous activity in the secondary somatosensory cortices predicted heightened pain perception in the individuals with cerebral palsy (P = 0.039). Overall, these results demonstrate that spontaneous cortical activity within individuals with cerebral palsy is altered in comparison to their neurotypical peers and may predict increased pain perception in this patient population. Potentially, changes in spontaneous resting-state activity may be utilized to measure the effectiveness of current treatment approaches that are directed at reducing the pain experienced by individuals with cerebral palsy.
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Affiliation(s)
- Michael P. Trevarrow
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
| | - Anna Reelfs
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
| | - Lauren R. Ott
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
| | - Samantha H. Penhale
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
| | - Brandon J. Lew
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
| | - Jessica Goeller
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Tony W. Wilson
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
- Department of Pharmacology & Neuroscience, Creighton University, Omaha, NE, USA
| | - Max J. Kurz
- Institute for Human Neuroscience, Boys Town National Research Hospital, Omaha, NE, USA
- Department of Pharmacology & Neuroscience, Creighton University, Omaha, NE, USA
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Ye X, Yang PF, Liu Q, Dillenburger BD, Friedman RM, Chen LM. A thermal nociceptive patch in the S2 cortex of nonhuman primates: a combined functional magnetic resonance imaging and electrophysiology study. Pain 2021; 162:2705-2716. [PMID: 33945242 PMCID: PMC8380756 DOI: 10.1097/j.pain.0000000000002247] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 02/18/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Human functional magnetic resonance imaging (fMRI) and behavioral studies have established the roles of cortical areas along the Sylvian fissure in sensing subjective pain. Yet, little is known about how sensory aspects of painful information are represented and processed by neurons in these regions and how their electrophysiological activities are related to fMRI signals. The current study aims to partially address this critical knowledge gap by performing fMRI-guided microelectrode mapping and recording studies in the homologous region of the parietal operculum in squirrel monkeys under light anesthesia. In each animal studied (n = 8), we detected mesoscale mini-networks for heat nociception in cortical regions around the lateral sulcus. Within the network, we discovered a ∼1.5 × 1.5-mm2-sized cortical patch that solely contained heat nociceptive neurons that aligned with the heat fMRI activation locus. These neurons responded slowly to thermal (heat and cold) nociceptive stimuli exclusively, continued firing for several seconds after the succession of stimulation, and exhibited multidigit receptive fields and high spontaneous firing rates. Similar to the fMRI responses, increasing temperatures in the nociceptive range led to a nonlinear increase in firing rates. The finding of a clustering of heat nociceptive neurons provides novel insights into the unique functional organization of thermal nociception in the S2 subregion of the primate brain. With fMRI, it supports the existence of a modality-preferred heat nociceptive patch that is spatially separated and intermingled with touch patches containing neurons with comparable receptive fields and the presence of functionally distinct mini-networks in primate opercular cortex.
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Affiliation(s)
- Xiang Ye
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Pai-Feng Yang
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Qing Liu
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Barbara D Dillenburger
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Robert M Friedman
- Department of Psychology, Vanderbilt University, Nashville, TN 37232, USA
| | - Li Min Chen
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Psychology, Vanderbilt University, Nashville, TN 37232, USA
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Su Q, Song Y, Zhao R, Liang M. A review on the ongoing quest for a pain signature in the human brain. BRAIN SCIENCE ADVANCES 2020. [DOI: 10.26599/bsa.2019.9050024] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Developing an objective biomarker for pain assessment is crucial for understanding neural coding mechanisms of pain in the human brain as well as for effective treatment of pain disorders. Neuroimaging techniques have been proven to be powerful tools in the ongoing quest for a pain signature in the human brain. Although there is still a long way to go before achieving a truly successful pain signature based on neuroimaging techniques, important progresses have been made through great efforts in the last two decades by the Pain Society. Here, we focus on neural responses to transient painful stimuli in healthy people, and review the relevant studies on the identification of a neuroimaging signature for pain.
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Affiliation(s)
- Qian Su
- Department of Molecular Imaging and Nuclear Medicine, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin’s Clinical Research Center for China, Tianjin 300060, China
- These authors contributed equally to this work
| | - Yingchao Song
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin 300070, China
- These authors contributed equally to this work
| | - Rui Zhao
- Department of Orthopedics Surgery, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Meng Liang
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin 300070, China
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Peyron R, Fauchon C. The posterior insular-opercular cortex: An access to the brain networks of thermosensory and nociceptive processes? Neurosci Lett 2019; 702:34-39. [DOI: 10.1016/j.neulet.2018.11.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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8
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Garcia-Larrea L, Bastuji H. Pain and consciousness. Prog Neuropsychopharmacol Biol Psychiatry 2018; 87:193-199. [PMID: 29031510 DOI: 10.1016/j.pnpbp.2017.10.007] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 10/08/2017] [Accepted: 10/09/2017] [Indexed: 01/18/2023]
Abstract
The aversive experience we call "pain" results from the coordinated activation of multiple brain areas, commonly described as a "pain matrix". This is not a fixed arrangement of structures but rather a fluid system composed of several interacting networks: A 'nociceptive matrix' includes regions receiving input from ascending nociceptive systems, and ensures the bodily characteristics of physical pain. A further set of structures receiving secondary input supports the 'salience' attributes of noxious stimuli, triggers top-down cognitive controls, and -most importantly- ensures the passage from pre-conscious nociception to conscious pain. Expectations and beliefs can still modulate the conscious experience via activity in supramodal regions with widespread cortical projections such as the ventral tegmental area. Intracortical EEG responses in humans show that nociceptive cortical processing is initiated in parallel in sensory, motor and limbic areas; it progresses rapidly to the recruitment of anterior insular and fronto-parietal networks, and finally to the activation of perigenual, posterior cingulate and hippocampal structures. Functional connectivity between sensory and high-level networks increases during the first second post-stimulus, which may be determinant for access to consciousness. A model is described, progressing from unconscious sensori-motor and limbic processing of spinothalamic and spino-parabrachial input, to an immediate sense of awareness supported by coordinated activity in sensorimotor and fronto-parieto-insular networks, and leading to full declarative consciousness through integration with autobiographical memories and self-awareness, involving posterior cingulate and medial temporal areas. This complete sequence is only present during full vigilance states. We contend, however, that even in unconscious subjects, repeated limbic and vegetative activation by painful stimuli via spino-amygdalar pathways can generate implicit memory traces and stimulus-response abnormal sequences, possibly contributing to long-standing anxiety or hyperalgesic syndromes in patients surviving coma.
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Affiliation(s)
- Luis Garcia-Larrea
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Universite Claude Bernard, Bron F-69677, France; Neurological Hospital Pain Center (CETD), Hôpital Neurologique, Hospices Civils De Lyon, Bron F-69677, France Lyon, France.
| | - Hélène Bastuji
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Universite Claude Bernard, Bron F-69677, France; Hypnology Unit, Functional Neurology and Epileptology Department, Hôpital Neurologique, Hospices Civils De Lyon, Bron, F-69677, France
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9
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Hagiwara K, Perchet C, Frot M, Bastuji H, Garcia-Larrea L. Insular-limbic dissociation to intra-epidermal electrical Aδ activation: A comparative study with thermo-nociceptive laser stimulation. Eur J Neurosci 2018; 48:3186-3198. [PMID: 30203624 DOI: 10.1111/ejn.14146] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/17/2018] [Accepted: 08/31/2018] [Indexed: 01/12/2023]
Abstract
Intra-epidermal electrical stimulation (IEES) has been shown to activate selectively Aδ fibers subserving spinothalamic-mediated sensations. Owing to electrically induced highly synchronous afferent volleys, IEES induces Aδ-mediated evoked potentials at nonpainful intensities, contrasting with thermo-nociceptive laser pulses which entail painful pricking sensations. Here, we recorded intracortical responses from sensory and limbic-cognitive regions of human subjects in response to IEE and laser stimuli, in order to test the hypothesis that IEES could dissociate the sensory from nonsensory networks of nociceptive processing. Intracortical evoked potentials were obtained in 11 epileptic patients with stereotactically implanted electrodes in sensory regions receiving spinothalamic afferents (posterior insula), limbic regions receiving spino-parabrachial input (amygdalar nucleus), and high-order affective-cognitive regions (anteromedial frontal cortex, including perigenual anterior cingulate and rostromedial prefrontal areas). Responses in the sensory posterior insula were of similar amplitude and latency to IEE and laser stimuli (after accounting for heat-transduction time of laser), and consistent in both cases with spinothalamic activation. However, responses to IEES in the amygdala and the anteromedial frontal regions were inconsistent and significantly smaller compared to those evoked to the laser stimulation. Thus, IEES can effectively activate the spinothalamic-sensory system with little recruitment of affective-motivational networks, including those triggered by spino-parabrachio-amygdalar projections. The fact that identical sensory responses were associated to either painful or nonpainful percepts underscores that subjective pain perception is not solely dependent on the sensory recruitment, but rather on the combined activation of sensory, limbic and cognitive areas with precise spatiotemporal relations.
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Affiliation(s)
- Koichi Hagiwara
- Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron, France.,Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan
| | - Caroline Perchet
- Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron, France
| | - Maud Frot
- Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron, France
| | - Hélène Bastuji
- Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron, France.,Unité D'Hypnologie, Service de Neurologie Fonctionnelle et d'Épileptologie, Hôpital Neurologique, Hospices Civils de Lyon, Bron, France
| | - Luis Garcia-Larrea
- Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron, France.,Centre D'évaluation et de Traitement de la Douleur, Hôpital Neurologique, Lyon, France
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Abstract
Pain was considered to be integrated subcortically during most of the 20th century, and it was not until 1956 that focal injury to the parietal opercular-insular cortex was shown to produce selective loss of pain senses. The parietal operculum and adjacent posterior insula are the main recipients of spinothalamic afferents in primates. The innermost operculum appears functionally associated with the posterior insula and can be segregated histologically, somatotopically and neurochemically from the more lateral S2 areas. The Posterior Insula and Medial Operculum (PIMO) encompass functional networks essential to initiate cortical nociceptive processing. Destruction of this region selectively abates pain sensations; direct stimulation generates acute pain, and epileptic foci trigger painful seizures. Lesions of the PIMO have also high potential to develop central pain with dissociated loss of pain and temperature. The PIMO region behaves as a somatosensory area on its own, which handles phylogenetically old somesthetic capabilities based on thinly myelinated or unmyelinated inputs. It integrates spinothalamic-driven information - not only nociceptive but also innocuous heat and cold, crude touch, itch, and possibly viscero-somatic interoception. Conversely, proprioception, graphesthesia or stereognosis are not processed in this area but in S1 cortices. Given its anatomo-functional properties, thalamic connections, and tight relations with limbic and multisensory cortices, the region comprising the inner parietal operculum and posterior insula appears to contain a third somatosensory cortex contributing to the spinothalamic attributes of the final perceptual experience.
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Affiliation(s)
- Luis Garcia-Larrea
- NeuroPain Laboratory, Lyon Centre for Neuroscience, Inserm U1028 and University Claude Bernard, Lyon, France; Center for the Evaluation and Treatment of Pain, Hôpital Neurologique, Hospices Civils de Lyon, Lyon, France.
| | - François Mauguière
- NeuroPain Laboratory, Lyon Centre for Neuroscience, Inserm U1028 and University Claude Bernard, Lyon, France; Functional Neurology Service, Hôpital Neurologique, Hospices Civils de Lyon, Lyon, France
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Bradley C, Bastuji H, Garcia-Larrea L. Evidence-based source modeling of nociceptive cortical responses: A direct comparison of scalp and intracranial activity in humans. Hum Brain Mapp 2017; 38:6083-6095. [PMID: 28925006 DOI: 10.1002/hbm.23812] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 08/27/2017] [Accepted: 09/05/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Source modeling of EEG traditionally relies on interplay between physiological hypotheses and mathematical estimates. We propose to optimize the process by using evidence gathered from brain imaging and intracortical recordings. METHODS We recorded laser-evoked potentials in 18 healthy participants, using high-density EEG. Brain sources were modeled during the first second poststimulus, constraining their initial position to regions where nociceptive-related activity has been ascertained by intracranial EEG. These comprised the two posterior operculo-insular regions, primary sensorimotor, posterior parietal, anterior cingulate/supplementary motor (ACC/SMA), bilateral frontal/anterior insular, and posterior cingulate (PCC) cortices. RESULTS The model yielded an average goodness of fit of 91% for individual and 95.8% for grand-average data. When compared with intracranial recordings from 27 human subjects, no significant difference in peak latencies was observed between modeled and intracranial data for 5 of the 6 assessable regions. Morphological match was excellent for operculo-insular, frontal, ACC/SMA and PCC regions (cross-correlation > 0.7) and fair for sensori-motor and posterior parietal cortex (c-c ∼ 0.5). CONCLUSIONS Multiple overlapping activities evoked by nociceptive input can be disentangled from high-density scalp EEG guided by intracranial data. Modeled sources accurately described the timing and morphology of most activities recorded with intracranial electrodes, including those coinciding with the emergence of stimulus awareness. Hum Brain Mapp 38:6083-6095, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Claire Bradley
- NEUROPAIN lab, Centre de Recherche en Neurosciences de Lyon, Inserm U1028 - CNRS UMR5292, Université Claude Bernard Lyon 1, Lyon, France
| | - Hélène Bastuji
- NEUROPAIN lab, Centre de Recherche en Neurosciences de Lyon, Inserm U1028 - CNRS UMR5292, Université Claude Bernard Lyon 1, Lyon, France
| | - Luis Garcia-Larrea
- NEUROPAIN lab, Centre de Recherche en Neurosciences de Lyon, Inserm U1028 - CNRS UMR5292, Université Claude Bernard Lyon 1, Lyon, France
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12
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Functional brain imaging: what has it brought to our understanding of neuropathic pain? A special focus on allodynic pain mechanisms. Pain 2016; 157 Suppl 1:S67-S71. [PMID: 26785157 DOI: 10.1097/j.pain.0000000000000387] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Brain responses to nociception are well identified. The same is not true for allodynic pain, a strong painful sensation in response to touch or innocuous cold stimuli that may be experienced by patients with neuropathic pain. Brain (or spinal cord) reorganization that may explain this paradoxical perception still remains largely unknown. Allodynic pain is associated with abnormally increased activity in SII and in the anterior insular cortex, contralateral and/or ipsilateral to allodynia. Because a bilateral increase in activity has been repeatedly reported in these areas in nociceptive conditions, the observed activation during allodynia can explain that a physiologically nonpainful stimulus could be perceived by the damaged nervous system as a painful one. Both secondary somatosensory and insular cortices receive input from the thalamus, which is a major relay of sensory and spinothalamic pathways, the involvement of which is known to be crucial for the development of neuropathic pain. Both thalamic function and structure have been reported to be abnormal or impaired in neuropathic pain conditions including in the basal state, possibly explaining the spontaneous component of neuropathic pain. A further indication as to how the brain can create neuropathic pain response in SII and insular cortices stems from examples of diseases, including single-case reports in whom a focal brain lesion leads to central pain disappearance. Additional studies are required to certify the contribution of these areas to the disease processes, to disentangle abnormalities respectively related to pain and to deafferentation, and, in the future, to guide targeting of stimulation studies.
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Bastuji H, Frot M, Perchet C, Magnin M, Garcia-Larrea L. Pain networks from the inside: Spatiotemporal analysis of brain responses leading from nociception to conscious perception. Hum Brain Mapp 2016; 37:4301-4315. [PMID: 27391083 DOI: 10.1002/hbm.23310] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/19/2016] [Accepted: 06/27/2016] [Indexed: 12/11/2022] Open
Abstract
Conscious perception of painful stimuli needs the contribution of an extensive cortico-subcortical network, and is completed in less than one second. While initial activities in operculo-insular and mid-cingulate cortices have been extensively assessed, the activation timing of most areas supporting conscious pain has barely been studied. Here we used intracranial EEG to investigate the dynamics of 16 brain regions (insular, parietal, prefrontal, cingulate, hippocampal and limbic) during the first second following nociceptive-specific laser pulses. Three waves of activation could be defined according to their temporal relation with conscious perception, ascertained by voluntary motor responses. Pre-conscious activities were recorded in the posterior insula, operculum, mid-cingulate and amygdala. Antero-insular, prefrontal and posterior parietal activities started later and developed during time-frames consistent with conscious voluntary reactions. Responses from hippocampus, perigenual and perisplenial cingulate developed latest and persisted well after conscious perception occurred. Nociceptive inputs reach simultaneously sensory and limbic networks, probably through parallel spino-thalamic and spino-parabrachial pathways, and the initial limbic activation precedes conscious perception of pain. Access of sensory information to consciousness develops concomitant to fronto-parietal activity, while late-occurring responses in the hippocampal region, perigenual and posterior cingulate cortices likely underlie processes linked to memory encoding, self-awareness and pain modulation. Hum Brain Mapp 37:4301-4315, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Hélène Bastuji
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028; CNRS, UMR5292, Université Claude Bernard, Bron, F-69677, France.,Unité D'Hypnologie, Service De Neurologie Fonctionnelle Et D'Épileptologie, Hôpital Neurologique, Hospices Civils De Lyon, Bron, F-69677, France
| | - Maud Frot
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028; CNRS, UMR5292, Université Claude Bernard, Bron, F-69677, France
| | - Caroline Perchet
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028; CNRS, UMR5292, Université Claude Bernard, Bron, F-69677, France
| | - Michel Magnin
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028; CNRS, UMR5292, Université Claude Bernard, Bron, F-69677, France
| | - Luis Garcia-Larrea
- Central Integration of Pain (NeuroPain) Lab - Lyon Neuroscience Research Center, INSERM U1028; CNRS, UMR5292, Université Claude Bernard, Bron, F-69677, France.,Centre D'évaluation Et De Traitement De La Douleur, Hôpital Neurologique, Lyon, France
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Abstract
The neural mechanisms of the powerful analgesia induced by touching a painful body part are controversial. A long tradition of neurophysiologic studies in anaesthetized spinal animals indicate that touch can gate nociceptive input at spinal level. In contrast, recent studies in awake humans have suggested that supraspinal mechanisms can be sufficient to drive touch-induced analgesia. To investigate this issue, we evaluated the modulation exerted by touch on established electrophysiologic markers of nociceptive function at both subcortical and cortical levels in humans. Aδ and C skin nociceptors were selectively activated by high-power laser pulses. As markers of subcortical and cortical function, we recorded the laser blink reflex, which is generated by brainstem circuits before the arrival of nociceptive signals at the cortex, and laser-evoked potentials, which reflect neural activity of a wide array of cortical areas. If subcortical nociceptive responses are inhibited by concomitant touch, supraspinal mechanisms alone are unlikely to be sufficient to drive touch-induced analgesia. Touch induced a clear analgesic effect, suppressed the laser blink reflex, and inhibited both Aδ-fibre and C-fibre laser-evoked potentials. Thus, we conclude that touch-induced analgesia is likely to be mediated by a subcortical gating of the ascending nociceptive input, which in turn results in a modulation of cortical responses. Hence, supraspinal mechanisms alone are not sufficient to mediate touch-induced analgesia.
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Nociceptive Local Field Potentials Recorded from the Human Insula Are Not Specific for Nociception. PLoS Biol 2016; 14:e1002345. [PMID: 26734726 PMCID: PMC4703221 DOI: 10.1371/journal.pbio.1002345] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 12/03/2015] [Indexed: 11/25/2022] Open
Abstract
The insula, particularly its posterior portion, is often regarded as a primary cortex for pain. However, this interpretation is largely based on reverse inference, and a specific involvement of the insula in pain has never been demonstrated. Taking advantage of the high spatiotemporal resolution of direct intracerebral recordings, we investigated whether the human insula exhibits local field potentials (LFPs) specific for pain. Forty-seven insular sites were investigated. Participants received brief stimuli belonging to four different modalities (nociceptive, vibrotactile, auditory, and visual). Both nociceptive stimuli and non-nociceptive vibrotactile, auditory, and visual stimuli elicited consistent LFPs in the posterior and anterior insula, with matching spatial distributions. Furthermore, a blind source separation procedure showed that nociceptive LFPs are largely explained by multimodal neural activity also contributing to non-nociceptive LFPs. By revealing that LFPs elicited by nociceptive stimuli reflect activity unrelated to nociception and pain, our results confute the widespread assumption that these brain responses are a signature for pain perception and its modulation. Local field potentials elicited in the human insular cortex by painful stimuli reflect cortical activity that is unrelated to pain perception and so cannot be used as an objective measure of pain. A widely accepted notion is that the insula, especially its posterior portion, plays a specific role in the perception of pain. This has led a number of researchers to consider activity recorded from this so-called “ouch zone” as an objective correlate of pain perception. We provide compelling evidence to the contrary. Using direct intracerebral recordings, we demonstrate that painful and nonpainful stimuli elicit very similar responses throughout the human insula. This observation argues against the notion that these responses reflect the brain activity through which pain emerges from nociception in the human brain. These findings have implications for basic theories, as well as for the development of diagnostic tests and the identification of therapeutic targets for the treatment of chronic pain. They question the use of these insular responses to assess the effects of pharmacological treatment or to assess pain in patients unable to communicate. Furthermore, they have legal implications, as they contradict the proposal that these responses could be used to determine unequivocally whether plaintiffs are truly experiencing the pain for which they are seeking redress. Finally, they undermine the rationale for neurosurgical procedures aiming at alleviating pain by targeting the posterior insula.
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Not an Aspirin: No Evidence for Acute Anti-Nociception to Laser-Evoked Pain After Motor Cortex rTMS in Healthy Humans. Brain Stimul 2016; 9:48-57. [DOI: 10.1016/j.brs.2015.08.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 08/18/2015] [Accepted: 08/28/2015] [Indexed: 02/06/2023] Open
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Testani E, Le Pera D, Del Percio C, Miliucci R, Brancucci A, Pazzaglia C, De Armas L, Babiloni C, Rossini PM, Valeriani M. Cortical inhibition of laser pain and laser-evoked potentials by non-nociceptive somatosensory input. Eur J Neurosci 2015; 42:2407-14. [DOI: 10.1111/ejn.13035] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 06/05/2015] [Accepted: 07/23/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Elisa Testani
- Department of Neurosciences; Catholic University; Rome Italy
| | - Domenica Le Pera
- Department of Neurology; IRCSS S. Raffaele Pisana, Tosinvest-Sanità; Rome Italy
| | | | - Roberto Miliucci
- Neurology Unit; Ospedale Pediatrico Bambino Gesú; IRCCS; Piazza Sant'Onofrio 4 Rome 00165 Italy
| | - Alfredo Brancucci
- Department of Psychological Sciences, Humanities and the Territory; ‘G. d'Annunzio’ University of Chieti and Pescara; Chieti Italy
| | - Costanza Pazzaglia
- Department of Neurology; Don Carlo Gnocchi Onlus Foundation; Milan Italy
| | - Liala De Armas
- Department of Neurology; IRCSS S. Raffaele Pisana, Tosinvest-Sanità; Rome Italy
| | - Claudio Babiloni
- EEG Lab; IRCSS S. Raffaele Pisana, Tosinvest-Sanità; Rome Italy
- Department of Physiology and Pharmacology; University of Rome ‘La Sapienza’; Rome Italy
| | | | - Massimiliano Valeriani
- Neurology Unit; Ospedale Pediatrico Bambino Gesú; IRCCS; Piazza Sant'Onofrio 4 Rome 00165 Italy
- Center for Sensory-Motor Interaction; Aalborg University; Aalborg Denmark
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Kim JH, Chien JH, Liu CC, Lenz FA. Painful cutaneous laser stimuli induce event-related gamma-band activity in the lateral thalamus of humans. J Neurophysiol 2015; 113:1564-73. [PMID: 25505116 PMCID: PMC4346717 DOI: 10.1152/jn.00778.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 12/09/2014] [Indexed: 11/22/2022] Open
Abstract
Although the thalamus is an important module in "pain networks," there are few studies of the effect of experimental pain upon thalamic oscillations. We have now examined the hypothesis that, during a series of painful cutaneous laser stimuli, thalamic signals will show stimulus-related gamma-band spectral activity, which is modulated by attention to vs. distraction from the painful stimulus. When the series of laser stimuli was presented, attention was focused by counting the laser stimuli (count laser task), while distraction was produced by counting backward (count back plus laser task). We have studied the effect of a cutaneous laser on thalamic local field potentials and EEG activity during awake procedures (deep brain stimulation implants) for the treatment of essential tremor. At different delays after the stimulus, three low gamma- (30-50 Hz) and two high gamma-band (70-90 Hz) activations were observed during the two tasks. Greater high-gamma activation was found during the count laser task for the earlier window, while greater high-gamma activation was found during the count back plus laser task for the later window. Thalamic signals were coherent with EEG signals in the beta band, which indicated significant synchrony. Thalamic cross-frequency coupling analysis indicated that the phase of the lower frequency activity (theta to beta) modulated the amplitude of the higher frequency activity (low and high gamma) more strongly during the count laser task than during the count back plus laser task. This modulation might result in multiplexed signals each encoding a different aspect of pain.
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Affiliation(s)
- J H Kim
- Department of Neurosurgery, Korea University, Guro Hospital, Seoul, South Korea
| | - J H Chien
- Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland; and
| | - C C Liu
- Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland; and
| | - F A Lenz
- Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland; and
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Garcia-Larrea L, Peyron R. Pain matrices and neuropathic pain matrices: A review. Pain 2013; 154 Suppl 1:S29-S43. [PMID: 24021862 DOI: 10.1016/j.pain.2013.09.001] [Citation(s) in RCA: 305] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 08/19/2013] [Accepted: 09/02/2013] [Indexed: 01/18/2023]
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20
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Bastuji H, Mazza S, Perchet C, Frot M, Mauguière F, Magnin M, Garcia-Larrea L. Filtering the reality: functional dissociation of lateral and medial pain systems during sleep in humans. Hum Brain Mapp 2012; 33:2638-49. [PMID: 21922606 PMCID: PMC6869894 DOI: 10.1002/hbm.21390] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 05/17/2011] [Accepted: 05/31/2011] [Indexed: 11/11/2022] Open
Abstract
Behavioral reactions to sensory stimuli during sleep are scarce despite preservation of sizeable cortical responses. To further understand such dissociation, we recorded intracortical field potentials to painful laser pulses in humans during waking and all-night sleep. Recordings were obtained from the three cortical structures receiving 95% of the spinothalamic cortical input in primates, namely the parietal operculum, posterior insula, and mid-anterior cingulate cortex. The dynamics of responses during sleep differed among cortical sites. In sleep Stage 2, evoked potential amplitudes were similarly attenuated relative to waking in all three cortical regions. During paradoxical, or rapid eye movements (REM), sleep, opercular and insular potentials remained stable in comparison with Stage 2, whereas the responses from mid-anterior cingulate abated drastically, and decreasing below background noise in half of the subjects. Thus, while the lateral operculo-insular system subserving sensory analysis of somatic stimuli remained active during paradoxical-REM sleep, mid-anterior cingulate processes related to orienting and avoidance behavior were suppressed. Dissociation between sensory and orienting-motor networks might explain why nociceptive stimuli can be either neglected or incorporated into dreams without awakening the subject.
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Affiliation(s)
- Hélène Bastuji
- Central Integration of Pain Lab-Lyon Neuroscience Research Center, INSERM, U1028, CNRS, UMR5292, Bron, F-69677, France.
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21
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Garcia-Larrea L. The posterior insular-opercular region and the search of a primary cortex for pain. Neurophysiol Clin 2012; 42:299-313. [DOI: 10.1016/j.neucli.2012.06.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 06/01/2012] [Accepted: 06/10/2012] [Indexed: 01/15/2023] Open
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22
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Garcia-Larrea L. Insights gained into pain processing from patients with focal brain lesions. Neurosci Lett 2012; 520:188-91. [DOI: 10.1016/j.neulet.2012.05.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/01/2012] [Accepted: 05/02/2012] [Indexed: 10/28/2022]
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23
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Hauck M, Bischoff P, Schmidt G, Zimmermann R, Lorenz J, Morrow TJ, Bromm B. Clonidine effects on pain evoked SII activity in humans. Eur J Pain 2012; 10:757-65. [PMID: 16439173 DOI: 10.1016/j.ejpain.2005.12.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Revised: 12/09/2005] [Accepted: 12/13/2005] [Indexed: 11/23/2022]
Abstract
We investigated pain evoked activity in the human secondary sensory cortex (SII) following clonidine administration in six healthy volunteers using multi-channel magnetoencephalography (MEG). Pain was elicited by electrical shocks applied intracutaneously to the fingertip. Subjects rated pain intensity and perceptions of tiredness and passiveness by numerical ranking scales. Each subject underwent two investigations, one week apart from each other, with clonidine doses of 1.5 or 3.0microg/kg, administered intravenously in a random order and double-blinded. We applied a total number of seven blocks, each consisting of 60 painful stimuli, with one adaptation block, one pre-medication block, four post-medication blocks and one recovery block at the end of the session. MEG data were analysed by dipole reconstruction using CURRY(R) (Neuroscan, Hamburg) software package. Cortical activity in the contralateral SII cortex appeared with peak latencies of 118.5+/-10ms. This activity was significantly reduced by clonidine, in parallel with a reduction of pain intensity and enhancement of subjective tiredness and passiveness. There was, however, no significant correlation between MEG and subjective effects. Although both clonidine doses had similar effects, the higher dose induced longer changes. Results indicate that intravenous clonidine is able to relieve pain, but the exact mechanism of clonidine at the level of the SII cortex remains unclear. It is possible that clonidine interacts with the brainstem ascending system regulating vigilance and arousal which would explain the observed decrement of pain induced activity in SII. An additional more specific analgesic action at spinal level cannot be excluded.
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Affiliation(s)
- Michael Hauck
- Institute of Physiology and Pathophysiology, University of Hamburg, Martinistrasse 52, D-20246 Hamburg, Germany
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24
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Liu CC, Ohara S, Franaszczuk PJ, Crone NE, Lenz FA. Attention to painful cutaneous laser stimuli evokes directed functional interactions between human sensory and modulatory pain-related cortical areas. Pain 2011; 152:2781-2791. [PMID: 22033363 PMCID: PMC3433227 DOI: 10.1016/j.pain.2011.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 08/25/2011] [Accepted: 09/01/2011] [Indexed: 12/30/2022]
Abstract
The human 'pain network' includes cortical areas that are activated during the response to painful stimuli (termed category 1) or during psychological processes that modulate pain, for example, distraction (termed category 2). These categories include parts of the parasylvian (PS), medial frontal (MF), and paracentral cortex (S1&M1). Here we test the hypothesis that causal interactions both within and between category 1 and category 2 modules occur during attention to a painful stimulus. Event-related causality (ERC) was calculated from local field potentials recorded directly from these cortical areas during the response to a painful cutaneous laser stimulus in patients being monitored for epilepsy. The number of electrodes involved in pairs with significant ERC in category 1 was greater for pre-stimulus vs post-stimulus and for attention vs distraction. This is consistent with our prior evidence that the category 1 'pain network' changes rapidly with time intervals and tasks. In contrast, the interaction between categories was often unchanged or stable across intervals and tasks, particularly in MF. The proportion of contacts involved in interactions with PS was greater during distraction vs attention while activation was less, which suggests that distraction involves an inhibitory process in PS. Functional interactions between categories were overwhelmingly in the direction from category 2>1, particularly for contacts in MF which often had a driver role. These results demonstrate that MF is densely interconnected throughout the 'pain network' so that stimulation of MF might be used to disrupt the 'pain network' as a therapy for pain.
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Affiliation(s)
- Chang-Chia Liu
- Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland, USA Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA
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Chen LM, Dillenburger BC, Wang F, Tang CH. Differential fMRI activation to noxious heat and tactile stimuli in parasylvian areas of new world monkeys. Pain 2011; 153:158-169. [PMID: 22115923 DOI: 10.1016/j.pain.2011.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 09/06/2011] [Accepted: 10/04/2011] [Indexed: 10/15/2022]
Abstract
Emerging evidence supports an important role of posterior parasylvian areas in both pain and touch processing. Whether there are separate or shared networks for these sensations remains controversial. The present study compared spatial patterns of brain activation in response to unilateral nociceptive heat (47.5°C) or innocuous tactile stimulation (8-Hz vibration) to digits through high-resolution functional magnetic resonance imaging (fMRI) in squirrel monkeys. In addition, the temporal profile of heat-stimulus-evoked fMRI Blood Oxygenation Level Dependent (BOLD) signal changes was characterized. By examining high-resolution fMRI and histological measures at both the individual and the group levels, we found that both nociceptive heat and tactile stimuli elicited activation in bilateral secondary somatosensory and ventral parietal areas (S2/PV) and in ipsilateral ventral somatosensory areas (VS) and retroinsula (Ri). Bilateral posterior insular cortex (pIns) and area 7b responded preferentially to nociceptive heat stimulation. Single voxels within each activation cluster showed robust BOLD signal changes during each block of nociceptive stimulation. Across animals (n=11), nociceptive response magnitudes of contralateral VS and pIns and ipsilateral Ri were significantly greater than corresponding areas in the opposite hemisphere. In sum, both distinct and shared areas in regions surrounding the posterior sylvian fissure were activated in response to nociceptive and tactile inputs in nonhuman primates.
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Affiliation(s)
- Li Min Chen
- Department of Radiology and Radiological Science, Vanderbilt University, Nashville, TN, USA Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA
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26
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Valentini E, Hu L, Chakrabarti B, Hu Y, Aglioti SM, Iannetti GD. The primary somatosensory cortex largely contributes to the early part of the cortical response elicited by nociceptive stimuli. Neuroimage 2011; 59:1571-81. [PMID: 21906686 DOI: 10.1016/j.neuroimage.2011.08.069] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 08/18/2011] [Accepted: 08/21/2011] [Indexed: 10/17/2022] Open
Abstract
Research on the cortical sources of nociceptive laser-evoked brain potentials (LEPs) began almost two decades ago (Tarkka and Treede, 1993). Whereas there is a large consensus on the sources of the late part of the LEP waveform (N2 and P2 waves), the relative contribution of the primary somatosensory cortex (S1) to the early part of the LEP waveform (N1 wave) is still debated. To address this issue we recorded LEPs elicited by the stimulation of four limbs in a large population (n=35). Early LEP generators were estimated both at single-subject and group level, using three different approaches: distributed source analysis, dipolar source modeling, and probabilistic independent component analysis (ICA). We show that the scalp distribution of the earliest LEP response to hand stimulation was maximal over the central-parietal electrodes contralateral to the stimulated side, while that of the earliest LEP response to foot stimulation was maximal over the central-parietal midline electrodes. Crucially, all three approaches indicated hand and foot S1 areas as generators of the earliest LEP response. Altogether, these findings indicate that the earliest part of the scalp response elicited by a selective nociceptive stimulus is largely explained by activity in the contralateral S1, with negligible contribution from the secondary somatosensory cortex (S2).
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Affiliation(s)
- E Valentini
- Department of Neuroscience, Physiology and Pharmacology, University College London, UK
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27
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Baumgärtner U, Vogel H, Ohara S, Treede RD, Lenz F. Dipole source analyses of laser evoked potentials obtained from subdural grid recordings from primary somatic sensory cortex. J Neurophysiol 2011; 106:722-30. [PMID: 21593389 DOI: 10.1152/jn.00135.2011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The cortical potentials evoked by cutaneous application of a laser stimulus (laser evoked potentials, LEP) often include potentials in the primary somatic sensory cortex (S1), which may be located within the subdivisions of S1 including Brodmann areas 3A, 3B, 1, and 2. The precise location of the LEP generator may clarify the pattern of activation of human S1 by painful stimuli. We now test the hypothesis that the generators of the LEP are located in human Brodmann area 1 or 3A within S1. Local field potential (LFP) source analysis of the LEP was obtained from subdural grids over sensorimotor cortex in two patients undergoing epilepsy surgery. The relationship of LEP dipoles was compared with dipoles for somatic sensory potentials evoked by median nerve stimulation (SEP) and recorded in area 3B (see Baumgärtner U, Vogel H, Ohara S, Treede RD, Lenz FA. J Neurophysiol 104: 3029-3041, 2010). Both patients had an early radial dipole in S1. The LEP dipole was located medial, anterior, and deep to the SEP dipole, which suggests a nociceptive dipole in area 3A. One patient had a later tangential dipole with positivity posterior, which is opposite to the orientation of the SEP dipole in area 3B. The reversal of orientations between modalities is consistent with the cortical surface negative orientation resulting from superficial termination of thalamocortical neurons that receive inputs from the spinothalamic tract. Therefore, the present results suggest that the LEP may result in a radial dipole consistent with a generator in area 3A and a putative later tangential generator in area 3B.
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Affiliation(s)
- Ulf Baumgärtner
- Center for Biomedicine and Medical Technology Mannheim (CBTM), Ruprecht-Karls-University Heidelberg, Mannheim, Germany
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28
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Liu CC, Ohara S, Franaszczuk PJ, Lenz FA. Attention to painful cutaneous laser stimuli evokes directed functional connectivity between activity recorded directly from human pain-related cortical structures. Pain 2011; 152:664-675. [PMID: 21255929 PMCID: PMC3043083 DOI: 10.1016/j.pain.2010.12.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 12/10/2010] [Accepted: 12/10/2010] [Indexed: 01/14/2023]
Abstract
Our previous studies show that attention to painful cutaneous laser stimuli is associated with functional connectivity between human primary somatosensory cortex (SI), parasylvian cortex (PS), and medial frontal cortex (MF), which may constitute a pain network. However, the direction of functional connections within this network is unknown. We now test the hypothesis that activity recorded from the SI has a driver role, and a causal influence, with respect to activity recorded from PS and MF during attention to a laser. Local field potentials (LFP) were recorded from subdural grid electrodes implanted for the treatment of epilepsy. We estimated causal influences by using the Granger causality (GRC), which was computed while subjects performed either an attention task (counting laser stimuli) or a distraction task (reading for comprehension). Before the laser stimuli, directed attention to the painful stimulus (counting) consistently increased the number of GRC pairs both within the SI cortex and from SI upon PS (SI>PS). After the laser stimulus, attention to a painful stimulus increased the number of GRC pairs from SI>PS, and SI>MF, and within the SI area. LFP at some electrode sites (critical sites) exerted GRC influences upon signals at multiple widespread electrodes, both in other cortical areas and within the area where the critical site was located. Critical sites may bind these areas together into a pain network, and disruption of that network by stimulation at critical sites might be used to treat pain. Electrical activity recorded from the somatosensory cortex drives activity recorded elsewhere in the pain network and may bind the network together; disruption of that network by stimulation at critical sites might be used to treat pain.
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Affiliation(s)
- C-C Liu
- Department of Neurosurgery, Johns Hopkins University, Baltimore, MD, USA Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
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Stephani C, Fernandez-Baca Vaca G, Maciunas R, Koubeissi M, Lüders HO. Functional neuroanatomy of the insular lobe. Brain Struct Funct 2010; 216:137-49. [PMID: 21153903 PMCID: PMC3097350 DOI: 10.1007/s00429-010-0296-3] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Accepted: 11/25/2010] [Indexed: 12/20/2022]
Abstract
The insula is the fifth lobe of the brain and it is the least known. Hidden under the temporal, frontal and parietal opercula, as well as under dense arterial and venous vessels, its accessibility is particularly restricted. Functional data on this region in humans, therefore, are scarce and the existing evidence makes conclusions on its functional and somatotopic organization difficult. 5 patients with intractable epilepsy underwent an invasive presurgical evaluation with implantation of diagnostic invasive-depth electrodes, including insular electrodes that were inserted using a mesiocaudodorsal to laterorostroventral approach. Altogether 113 contacts were found to be in the insula and were stimulated with alternating currents during preoperative monitoring. Different viscerosensitive and somatosensory phenomena were elicited by stimulation of these electrodes. A relatively high density of electrode contacts enabled us to delineate several functionally distinct areas within the insula. We found somatosensory symptoms to be restricted to the posterior insula and a subgroup of warmth or painful sensations in the dorsal posterior insula. Viscerosensory symptoms were elicited by more anterior electrode contacts with a subgroup of gustatory symptoms occurring after stimulation of electrode contacts in the central part of the insula. The anterior insula did not show reproducible responses to stimulation. In line with previous studies, we found evidence for somato- and viscerosensory cortex in the insula. In addition, our results suggest that there is a predominantly posterior and central distribution of these functions in the insular lobe.
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Affiliation(s)
- C Stephani
- The Neurological Institute, Department of Neurology, University Hospitals Case Medical Center, 11100 Euclid Avenue, Cleveland, OH 44106, USA.
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Garcia-Larrea L, Perchet C, Creac'h C, Convers P, Peyron R, Laurent B, Mauguière F, Magnin M. Operculo-insular pain (parasylvian pain): a distinct central pain syndrome. Brain 2010; 133:2528-39. [PMID: 20724291 DOI: 10.1093/brain/awq220] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Central pain with dissociated thermoalgesic sensory loss is common in spinal and brainstem syndromes but not in cortical lesions. Out of a series of 270 patients investigated because of somatosensory abnormalities, we identified five subjects presenting with central pain and pure thermoalgesic sensory loss contralateral to cortical stroke. All of the patients had involvement of the posterior insula and inner parietal operculum. Lemniscal sensory modalities (position sense, graphaestesia, stereognosis) and somatosensory evoked potentials to non-noxious inputs were always preserved, while thermal and pain sensations were profoundly altered, and laser-evoked potentials to thermo-nocoiceptive stimuli were always abnormal. Central pain resulting from posterior parasylvian lesions appears to be a distinct entity that can be identified unambiguously on the basis of clinical, radiological and electrophysiological data. It presents with predominant or isolated deficits for pain and temperature sensations, and is paradoxically closer to pain syndromes from brainstem lesions affecting selectively the spinothalamic pathways than to those caused by focal lesions of the posterior thalamus. The term 'pseudo-thalamic' is therefore inappropriate to describe it, and we propose parasylvian or operculo-insular pain as appropriate labels. Parasylvian pain may be extremely difficult to treat; the magnitude of pain-temperature sensory disturbances may be prognostic for its development, hence the importance of early sensory assessment with quantitative methods.
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Affiliation(s)
- Luis Garcia-Larrea
- Central Integration of Pain Unit, U879 INSERM & University Claude Bernard, Lyon 1, Neurological Hospital, Lyon, France.
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Veldhuijzen DS, Greenspan JD, Kim JH, Lenz FA. Altered pain and thermal sensation in subjects with isolated parietal and insular cortical lesions. Eur J Pain 2010; 14:535.e1-11. [PMID: 19939715 PMCID: PMC2872197 DOI: 10.1016/j.ejpain.2009.10.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Revised: 09/04/2009] [Accepted: 10/02/2009] [Indexed: 11/21/2022]
Abstract
Studies of sensory function following cortical lesions have often included lesions which multiple cortical, white matter, and thalamic structures. We now test the hypothesis that lesions anatomically constrained to particular insular and parietal structures and their subjacent white matter are associated with different patterns of sensory loss. Sensory loss was measured by quantitative sensory testing (QST), and evaluated statistically within patients relative to normal values. All seven subjects with insular and/or parietal lesions demonstrated thermal hypoesthesia, although the etiology of the lesions was heterogeneous. Cold and heat hypoalgesia were only found in the subject with the most extensive parietal and insular lesion, which occurred in utero. Cold allodynia occurred clinically and by thresholds in two subjects with isolated ischemic lesions of the posterior insular/retroinsular cortex, and by thresholds in two subjects with a lesion of parietal cortex with little or no insular involvement. Central pain occurred in the two subjects with clinical allodynia secondary to isolated lesions of the posterior insular/retroinsular cortex, which spared the anterior and posterior parietal cortex. These results suggest that nonpainful cold and heat sensations are jointly mediated by parietal and insular cortical structures so that lesions anywhere in this system may diminish sensitivity. In contrast, thermal pain is more robust requiring larger cortical lesions of these same structures to produce hypoalgesia. In addition, cold allodynia can result from restricted lesions that also produce thermal hypoesthesia, but not from all such lesions.
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Affiliation(s)
- D S Veldhuijzen
- Division of Perioperative Care and Emergency Medicine, Rudolf Magus Institute of Neuroscience, Pain Clinic, University Medical Center Utrecht, Utrecht, Netherlands
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A new Kalman filter approach for the estimation of high-dimensional time-variant multivariate AR models and its application in analysis of laser-evoked brain potentials. Neuroimage 2010; 50:960-9. [DOI: 10.1016/j.neuroimage.2009.12.110] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 12/22/2009] [Accepted: 12/23/2009] [Indexed: 12/24/2022] Open
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Liu CC, Ohara S, Franaszczuk P, Zagzoog N, Gallagher M, Lenz FA. Painful stimuli evoke potentials recorded from the medial temporal lobe in humans. Neuroscience 2009; 165:1402-11. [PMID: 19925853 DOI: 10.1016/j.neuroscience.2009.11.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 11/09/2009] [Accepted: 11/10/2009] [Indexed: 10/20/2022]
Abstract
The role of human medial temporal structures in fear conditioning has led to the suggestion that neurons in these structures might respond to painful stimuli. We have now tested the hypothesis that recordings from these structures will demonstrate potentials related to the selective activation of cutaneous nociceptors by a painful laser stimulus (laser evoked potential, LEP) (Kenton B, Coger R, Crue B, Pinsky J, Friedman Y, Carmon A (1980) Neurosci Lett 17:301-306). Recordings were carried out through electrodes implanted bilaterally in these structures for the investigation of intractable epilepsy. Reproducible LEPs were commonly recorded both bilaterally and unilaterally, while LEPs were recorded at contacts on the left (9/14, P=0.257) as commonly as on the right (5/14), independent of the hand stimulated. Along electrodes traversing the amygdala the majority of LEPs were recorded from dorsal contacts near the central nucleus of the amygdala and the nucleus basalis. Stimulus evoked changes in theta activity were observed at contacts on the right at which isolated early negative LEPs (N2*) responses could be recorded. Contacts at which LEPs could be recorded were as commonly located in medial temporal structures with evidence of seizure activity as on those without. These results demonstrate the presence of pain-related inputs to the medial temporal lobe where they may be involved in associative learning to produce anxiety and disability related to painful stimuli.
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Affiliation(s)
- C C Liu
- Department of Neurosurgery, Meyer 5-181, Johns Hopkins University, Baltimore, MD 21287-7713, USA
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Abstract
OBJECTIVE This study is aimed to explore the frequency characteristics of pain-evoked neuromagnetic responses in the secondary somatosensory (SII) cortices. METHODS Thulium-laser nociceptive stimuli to the left hand dorsum of 10 right-handed healthy adults. The pain stimuli were rated as mild, moderate, and severe levels according to subjects' reports on a 10-point visual analog scale. We analyzed their cortical responses with wavelet-based frequency analyses and equivalent current dipole (ECD) modeling. RESULTS For each pain level, we found an increase of theta (4-8 Hz) and alpha (8-13 Hz) power in bilateral SII areas at 180-210 ms after stimulus onset. The power was larger for the moderate than for the mild pain level (p < 0.05), but there was no statistical power difference of these oscillations between moderate and severe pain stimulus conditions (p = 0.7). Within the SII area, we did not observe particular difference in theta and alpha ECD locations between varying pain level conditions. CONCLUSIONS The 4-13 Hz activities, peaking from 180 to 210 ms, are oscillatory correlates of SII activation in response to nociceptive stimulation, but their power may code the magnitude of pain stimuli only up to moderate level, as rated subjectively. This measure could be potentially used to evaluate SII activation in further pain studies.
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Mouraux A, Iannetti GD. Nociceptive laser-evoked brain potentials do not reflect nociceptive-specific neural activity. J Neurophysiol 2009; 101:3258-69. [PMID: 19339457 DOI: 10.1152/jn.91181.2008] [Citation(s) in RCA: 271] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Brief radiant laser pulses can be used to activate cutaneous Adelta and C nociceptors selectively and elicit a number of transient brain responses [laser-evoked potentials (LEPs)] in the ongoing EEG. LEPs have been used extensively in the past 30 years to gain knowledge about the cortical mechanisms underlying nociception and pain in humans, by assuming that they reflect at least neural activities uniquely or preferentially involved in processing nociceptive input. Here, by applying a novel blind source separation algorithm (probabilistic independent component analysis) to 124-channel event-related potentials elicited by a random sequence of nociceptive and non-nociceptive somatosensory, auditory, and visual stimuli, we provide compelling evidence that this assumption is incorrect: LEPs do not reflect nociceptive-specific neural activity. Indeed, our results indicate that LEPs can be entirely explained by a combination of multimodal neural activities (i.e., activities also elicited by stimuli of other sensory modalities) and somatosensory-specific, but not nociceptive-specific, neural activities (i.e., activities elicited by both nociceptive and non-nociceptive somatosensory stimuli). Regardless of the sensory modality of the eliciting stimulus, the magnitude of multimodal activities correlated with the subjective rating of saliency, suggesting that these multimodal activities are involved in stimulus-triggered mechanisms of arousal or attentional reorientation.
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Affiliation(s)
- A Mouraux
- Department of Clinical Neurology, University of Oxford, OX1 3QX Oxford, United Kingdom
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Valeriani M, Truini A, Le Pera D, Insola A, Galeotti F, Petrachi C, Mazzone P, Cruccu G. Laser evoked potential recording from intracerebral deep electrodes. Clin Neurophysiol 2009; 120:790-5. [PMID: 19303809 DOI: 10.1016/j.clinph.2009.02.162] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 02/06/2009] [Accepted: 02/13/2009] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To investigate whether recording from deep intracerebral (IC) electrodes can disclose laser evoked potential (LEP) components generated under the cerebral cortex. METHODS LEPs were recorded to hand and/or perioral region stimulation from 7 patients suffering from Parkinson's disease, who underwent implant of IC electrodes in the globus pallidum pars interna (GPi), in the subthalamic nucleus (STN) and in the pedunculopontine nucleus (PPN). LEPs were obtained from the IC electrode contacts and from the Cz vertex, referred to the nose. RESULTS The scalp traces showed a triphasic response (P1-N2-P2). The IC electrodes recorded two main components (ICP2 and ICN2), showing the same latencies as the scalp N2 and P2 potentials, respectively. The ICP2-ICN2 complex was sometimes preceded by a ICP1 wave at the same latency of the scalp P1 response. CONCLUSIONS The LEP components recorded from the IC electrodes mirrored the ones picked up from the Cz lead, thus suggesting that they are probably generated by the opposite pole of the same cortical sources producing the scalp responses. SIGNIFICANCE In the IC traces, there was no evidence of earlier potentials possibly generated within the thalamus or of subcortical far-field responses. This means that the nociceptive signal amplification occurring within the cerebral cortex is necessary to produce identifiable LEP components.
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Affiliation(s)
- Massimiliano Valeriani
- Division of Neurology, Ospedale Pediatrico Bambino Gesù, IRCCS, Piazza Sant'Onofrio 4, 00165 Rome, Italy.
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Kobayashi K, Winberry J, Liu CC, Treede RD, Lenz FA. A painful cutaneous laser stimulus evokes responses from single neurons in the human thalamic principal somatic sensory nucleus ventral caudal (Vc). J Neurophysiol 2009; 101:2210-7. [PMID: 19244350 DOI: 10.1152/jn.91347.2008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cutaneous application of painful radiant heat laser pulses evokes potentials (laser-evoked potentials) that can be recorded from scalp or intracranial electrodes. We have now tested the hypothesis that the response of thalamic neurons to a cutaneous laser stimulus occurs at latencies predicted by the conduction delay between the periphery and the thalamus. We have carried out recordings from human thalamic neurons in the principal sensory nucleus (ventral caudal) in patients undergoing awake surgery for the treatment of tremor. The results demonstrate that many neurons respond to the laser with early and/or late latency peaks of activity, consistent with conduction of the response to the laser stimulus through pathways from Adelta and C fibers to the thalamus. These peaks were of short duration, perhaps due to the somatotopic- and modality-specific arrangements of afferent pathways to the thalamus. The responses of these thalamic neurons to the laser stimulus sometimes included low-threshold spike (LTS) bursts of action potentials, consistent with previous studies of different painful stimuli. A prior study has demonstrated that spike trains characterized by common LTS bursts such as the intermediate (I) category spontaneously change their category more commonly than do those without LTS bursts (NG: nongrouped category) during changes in the cognitive task. Spike trains of laser-responsive neurons were more common in the I category, whereas those of laser nonresponsive neurons were more common in the NG category. Therefore neuronal spike trains in the I category may mediate shifts in endogenous or cognitive pain-related behavior.
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Affiliation(s)
- K Kobayashi
- Department of Neurosurgery, Johns Hopkins Hospital, Meyer Building 8-181, 600 North Wolfe Street, Baltimore, MD 21287-7713, USA
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Quality discrimination for noxious stimuli in secondary somatosensory cortex: a MEG-study. Eur J Pain 2009; 13:1048.e1-7. [PMID: 19231261 DOI: 10.1016/j.ejpain.2009.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 01/04/2009] [Accepted: 01/18/2009] [Indexed: 11/22/2022]
Abstract
A complex cortical network is believed to encode the multi-dimensionality of the human pain experience. In the present study, we used magnetoencephalography (MEG) to examine whether the cortical processing of noxious stimuli with different psychophysical properties differs in primary (S1) and secondary (S2) somatosensory cortices. Noxious low (condition 1) and high (condition 2) current density stimulations of equal stimulus intensities were applied at the left forearm in 12 subjects in a randomised order. Concomitantly, subjects had to evaluate the corresponding sensory-discriminative and affective-motivational pain dimensions. MEG revealed an increased activation of bilateral secondary somatosensory cortices (S2) during condition 2 compared to condition 1. Higher activations of bilateral S2 were significantly correlated with higher scores for the sensory-discriminative component during condition 2. In contrast, corresponding scores for the affective-motivational pain dimension did not differ between both conditions. Therefore, concerning the sensory dimension of the human pain experience we conclude that the S2 cortex is involved in the encoding of quality discrimination.
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Herrndobler F, Koppert W, Ringler R, Maihöfner C. Modulation der kortikalen Schmerzverarbeitung durch Cyclooxygenase-Hemmung. Schmerz 2008; 23:134-44. [DOI: 10.1007/s00482-008-0732-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Greenspan JD, Coghill RC, Gilron I, Sarlani E, Veldhuijzen D, Lenz FA. Quantitative somatic sensory testing and functional imaging of the response to painful stimuli before and after cingulotomy for obsessive-compulsive disorder (OCD). Eur J Pain 2008; 12:990-9. [PMID: 18328752 PMCID: PMC3338983 DOI: 10.1016/j.ejpain.2008.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2007] [Revised: 12/15/2007] [Accepted: 01/23/2008] [Indexed: 10/22/2022]
Abstract
The middle cingulate cortex (MCC) has been implicated in pain processing by studies of cingulotomy for chronic pain and imaging studies documenting increased MCC blood flow in response to acute pain. The only previous report of quantitative sensory testing following cingulotomy described increased intensity and unpleasantness ratings of painful hot and cold stimuli in a single patient with psychiatric disease. We now report a case in which perception of pain and temperature was assessed before and after cingulotomy for obsessive-compulsive disorder (OCD). Positron emission tomographic (PET) studies of the blood flow response to acute pain were carried out using a single subject design which allowed for statistical evaluation of postoperative blood flow changes in this case. Postoperatively, the patient demonstrated increased intensity and unpleasantness ratings of painful thermal waterbath stimuli. The PET studies demonstrated preoperative contact heat pain-evoked activation of the bilateral MCC/SMA (supplementary motor area) and the left (contralateral) fronto-parietal operculum. Postoperative pain-evoked activation was demonstrated in the right (ipsilateral) parasylvian cortex but not of the MCC/SMA. Prior studies of forebrain lesions, and of cortical synchrony during the application of painful stimuli suggest the presence of functional connectivity between components of the MCC/SMA and the fronto-parietal opercula. Therefore present results suggest that cingulate lesions disinhibit ipsilateral parasylvian cortex and so are independent evidence of functional connectivity between these cortical areas, the defining characteristic of modules in a pain network.
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Affiliation(s)
- Joel D. Greenspan
- Dept. of Biomedical Sciences, School of Dentistry, and Program in Neuroscience, University of Maryland, Baltimore, MD, USA
| | - Robert C. Coghill
- Dept. of Neurobiology & Anatomy, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Ian Gilron
- Departments of Anesthesiology and of Pharmacology & Toxicology Queen’s University, Kingston, Ontario, Canada
| | - Eleni Sarlani
- Dept. of Biomedical Sciences, School of Dentistry, and Program in Neuroscience, University of Maryland, Baltimore, MD, USA
| | - Dieuwke Veldhuijzen
- Dept. of Biomedical Sciences, School of Dentistry, and Program in Neuroscience, University of Maryland, Baltimore, MD, USA
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Greenspan JD, Ohara S, Franaszczuk P, Veldhuijzen DS, Lenz FA. Cold stimuli evoke potentials that can be recorded directly from parasylvian cortex in humans. J Neurophysiol 2008; 100:2282-6. [PMID: 18579655 PMCID: PMC2576208 DOI: 10.1152/jn.90564.2008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 06/20/2008] [Indexed: 11/22/2022] Open
Abstract
Anatomic, imaging, and lesion studies suggest that insular or parietal opercular cortical structures mediate the sensation of nonpainful cold. We have now tested the hypothesis that cold stimuli evoke electrical responses from these cortical structures in humans. We recorded the response to cold stimuli from electrodes implanted directly over parasylvian cortex for the investigation of intractable seizures. The results demonstrate that slow potentials can be evoked consistently over structures adjacent to the sylvian fissure in response to nonpainful cold. The polarity of these cold evoked potentials (EPs) for electrodes above the sylvian fissure is opposite to those below. These results suggest that the generator of cold EPs is close to the sylvian fissure in the parietal operculum or insula.
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Affiliation(s)
- J D Greenspan
- Department of Neurosurgery, Johns Hopkins Hospital, and Department of Biomedical Sciences, University of Maryland Dental School, Meyer Building 8-181, 600 North Wolfe Street, Baltimore, MD 21287-7713, USA
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Boyle Y, El-Deredy W, Montes EM, Bentley DE, Jones AK. Selective modulation of nociceptive processing due to noise distraction. Pain 2008; 138:630-640. [DOI: 10.1016/j.pain.2008.02.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 01/28/2008] [Accepted: 02/20/2008] [Indexed: 01/21/2023]
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Dowman R, Rissacher D, Schuckers S. EEG indices of tonic pain-related activity in the somatosensory cortices. Clin Neurophysiol 2008; 119:1201-12. [PMID: 18337168 PMCID: PMC2676940 DOI: 10.1016/j.clinph.2008.01.019] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Revised: 12/03/2007] [Accepted: 01/25/2008] [Indexed: 01/01/2023]
Abstract
OBJECTIVE To identify EEG features that index pain-related cortical activity, and to identify factors that can mask the pain-related EEG features and/or produce features that can be misinterpreted as pain-specific. METHODS The EEG was recorded during three conditions presented in counterbalanced order: a tonic cold pain condition, and pain anticipation and arithmetic control conditions. The EEG was also recorded while the subjects made a wincing facial expression to estimate the contribution of scalp EMG artifacts to the pain-related EEG features. RESULTS Alpha amplitudes decreased over the contralateral temporal scalp and increased over the posterior scalp during the cold pain condition. There was an increase in gamma band activity during the cold pain condition at most electrode locations that was due to EMG artifacts. CONCLUSIONS The decrease in alpha over the contralateral temporal scalp during cold pain is consistent with pain-related activity in the primary somatosensory cortex and/or the somatosensory association areas located in the parietal operculum and/or insula. This study also identified factors that might mask the pain-related EEG features and/or generate EEG features that could be misinterpreted as being pain-specific. These include (but are not limited to) an increase in alpha generated in the visual cortex that results from attention being drawn towards the pain; the widespread increase in gamma band activity that results from scalp EMG generated by the facial expressions that often accompany pain; and the possibility that non-specific changes in the EEG over time mask the pain-related EEG features when the pain and control conditions are given in the same order across subjects. SIGNIFICANCE This study identified several factors that need to be controlled and/or isolated in order to successfully record EEG features that index pain-related activity in the somatosensory cortices.
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Affiliation(s)
- Robert Dowman
- Department of Psychology, Clarkson University, Potsdam, NY 13699-5825, USA.
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Weiss T, Hesse W, Ungureanu M, Hecht H, Leistritz L, Witte H, Miltner WHR. How Do Brain Areas Communicate During the Processing of Noxious Stimuli? An Analysis of Laser-Evoked Event-Related Potentials Using the Granger Causality Index. J Neurophysiol 2008; 99:2220-31. [DOI: 10.1152/jn.00912.2007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Several imaging techniques have identified different brain areas involved in the processing of noxious stimulation and thus in the constitution of pain. However, only little is known how these brain areas communicate with one another after activation by stimulus processing and which areas directionally affect or modulate the activity of succeeding areas. One measure for the analysis of such interactions is represented by the Granger Causality Index (GCI). In applying time-varying bivariate and partial variants of this concept (tvGCI), the aim of the present study was to investigate the interaction of neural activities between a set of scalp electrodes that best represent the brain electrical neural activity of major cortical areas involved in the processing of noxious laser-heat stimuli and their variation in time. Bivariate and partial tvGCIs were calculated within four different intervals of laser-evoked event-related potentials (LEPs) including a baseline period prior to stimulus application and three intervals immediately following stimulus application, i.e., between 170 and 200 ms (at the N2 component), between 260 and 320 ms (P2 component), and between 320 and 400 ms (P3 component of LEPs). Results show some similarities, but also some striking differences between bivariate and partial tvGCIs. These differences might be explained by the nature of bivariate and partial tvGCIs. However, both tvGCI approaches revealed a directed interaction between medial and lateral electrodes of the centroparietal region. This result was interpreted as a directed interaction between the anterior cingulate cortex and the secondary somatosensory cortex and the insula, structures that are significantly involved in the constitution of pain.
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Ohara S, Crone NE, Weiss N, Kim JH, Lenz FA. Analysis of synchrony demonstrates that the presence of "pain networks" prior to a noxious stimulus can enable the perception of pain in response to that stimulus. Exp Brain Res 2008; 185:353-8. [PMID: 18231782 DOI: 10.1007/s00221-008-1284-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Accepted: 01/14/2008] [Indexed: 10/22/2022]
Abstract
Our previous study has shown that directed attention to a painful stimulus is associated with increased synchrony between electrocorticographic (ECoG) oscillations in pain-related cortical structures. We now test the hypothesis that the synchrony or functional connectivity of this pain network differs between events during which pain is or is not perceived (pain or non-pain events) in response to a noxious cutaneous laser stimulus. ECoG recordings were made through subdural electrodes implanted in a patient for the treatment of epilepsy. The patient was instructed that the stimulus could be painful or non-painful on any given presentation. Synchrony between ECoG signals at different sites was measured during the pre-stimulus interval, and the difference in the number of sites with significant pre-stimulus synchrony was compared between pain and non-pain events. Pre-stimulus synchrony was more common during pain versus non-pain events among electrodes overall, and in the subset of electrodes at which laser-evoked potentials (LEPs) were recorded. This difference between pain and non-pain events was also significant for the subset of electrodes over medial cortex, including anterior cingulate cortex (ACC), but not for subsets of electrodes over the superior and inferior convexity, including primary somatosensory (S1) and parasylvian cortex (PS), respectively. These results suggest that dynamic changes in the functional connectivity between ACC and other cortical regions enable the perception of pain in response to noxious stimuli.
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Affiliation(s)
- S Ohara
- Department of Neurosurgery, Johns Hopkins Hospital, Meyer Building 8-181, 600 North Wolfe Street, Baltimore, MD 21287-7713, USA
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Maihöfner C, Ringler R, Herrndobler F, Koppert W. Brain imaging of analgesic and antihyperalgesic effects of cyclooxygenase inhibition in an experimental human pain model: a functional MRI study. Eur J Neurosci 2007; 26:1344-56. [PMID: 17767511 DOI: 10.1111/j.1460-9568.2007.05733.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One of the most distressing symptoms of many neuropathic pain syndromes is the enhanced pain sensation to tactile or thermal stimulation (hyperalgesia). In the present study we used functional magnetic resonance imaging (fMRI) and explored brain activation patterns during acute impact pain and mechanical hyperalgesia in the human ultraviolet (UV)-B model. To investigate pharmacological modulation, we examined potential differential fMRI correlates of analgesic and antihyperalgesic effects of two intravenous cyclooxygenase inhibitors, i.e. parecoxib and acetylsalicylic acid (ASA). Fourteen healthy volunteers participated in this double-blinded, randomized and placebo-controlled crossover study. Tactile stimuli and mechanical impact hyperalgesia were tested at the site of a UV-B irradiation and acute mechanical pain was tested at a site distant from the irradiated skin. These measurements were conducted before and 30 min after a 5-min intravenous infusion of either saline (placebo), parecoxib 40 mg or ASA 1000 mg. Acute mechanical pain and mechanical hyperalgesia led to widespread activations of brain areas known to comprise the human pain matrix. Analgesic effects were found in primary (S1) and secondary (S2) somatosensory cortices, parietal association cortex (PA), insula, anterior parts of the cingulate cortex and prefrontal cortices. These brain areas were also modulated under antihyperalgesic conditions. However, we observed a greater drug-induced modulation of mainly PA and inferior frontal cortex during mechanical hyperalgesia; during acute mechanical pain there was a greater modulation of mainly bilateral S2. Therefore, the results of the present study suggest that there is a difference in the brain areas modulated by analgesia and antihyperalgesia.
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Affiliation(s)
- Christian Maihöfner
- Department of Neurology, Schwabachanlage 6, D91054 Erlangen, University Hospital Erlangen, Germany.
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Ohara S, Anderson WS, Lawson HC, Lee HT, Lenz FA. Endogenous and exogenous modulators of potentials evoked by a painful cutaneous laser (LEPs). ACTA NEUROCHIRURGICA. SUPPLEMENT 2007; 99:77-9. [PMID: 17370769 DOI: 10.1007/978-3-211-35205-2_15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Little is known about the specific functions of the human cortical structures receiving nociceptive input, their relationship to various dimensions of pain, and the modulation of these inputs by attention. We now review studies demonstrating the subdural potentials evoked by a cutaneous laser stimulus which produces a pure pain sensation by selective activation of cutaneous nociceptors (LEPs). These LEPs were localized over human anterior and middle cingulate (A & MCC), somatosensory (S1) and parasylvian (PS) cortices. LEP, lesion and imaging data define pain-related elements within each of these structures: insula and parietal operculum within PS, anterior and middle cingulate cortex, and possibly Brodman's areas 3a, 3b and 1 within SI. LEPs recorded over each of these areas is modulated with laser intensity and evoked pain. Attention to the painful laser produces an increase in the amplitude of LEPs over all three cortical areas and emergence of a late positive potential over ACC alone. These studies provide clear evidence of human cortical structures receiving nociceptive input and the modulation of that input by exogenous (e.g. laser intensity) and endogenous factors (e.g. directed attention).
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Affiliation(s)
- S Ohara
- Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, Maryland 21287-7713, USA
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Dowman R, Darcey T, Barkan H, Thadani V, Roberts D. Human intracranially-recorded cortical responses evoked by painful electrical stimulation of the sural nerve. Neuroimage 2007; 34:743-63. [PMID: 17097306 DOI: 10.1016/j.neuroimage.2006.09.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Revised: 08/02/2006] [Accepted: 09/14/2006] [Indexed: 12/21/2022] Open
Abstract
Intracranial recordings were obtained from 5 epilepsy patients to help identify the generators of the scalp somatosensory evoked potential (SEP) components that appear to be involved in orienting attention towards a potentially threatening, painful sural nerve electrical stimulus. The intracranial recording data support, for the most part, the generators suggested by our scalp SEP studies. The generators of the central negativity at 70-110 ms post-stimulus and the contralateral temporal negativity at 100-180 ms are located in the somatosensory association areas in the medial wall of the parietal cortex and in the parietal operculum and insula, respectively. The negative potential at 130-200 ms recorded from over the fronto-central scalp appears to be generated in the medial prefrontal cortex and primary somatosensory cortex foot area. The intracranial recording data suggest that the positive scalp potential at 280-320 ms, which corresponds to the pain-related P2, has multiple generators, including the anterior cingulate cortex, inferior parietal cortex, and possibly the somatosensory association areas in the medial wall of the parietal cortex. Finally, the positive scalp potential at 320-400 ms has generators in brain areas that others have shown to generate the P3a, including the dorsolateral and medial prefrontal cortices, temporal parietal junction, and the posterior hippocampus, which supports our hypothesis that this potential is a pain-evoked P3a. The putative functional roles of the brain areas generating these components and the response properties of the intracranial peaks recorded from these brain areas are in most cases consistent with the attention- and pain-related properties of their corresponding scalp SEP components. The intracranial recordings also demonstrate that the source configuration underlying the SEP components are often more complex than was suggested from the scalp studies. This complexity implies that the dipole source localization analysis of these components will at best provide only a very crude estimate of source location and activity, and that caution must be used when interpreting a change in the scalp component amplitude.
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Affiliation(s)
- R Dowman
- Department of Psychology, Clarkson University, Potsdam, NY 13699-5825, USA.
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Fisiologia del dolore. Neurologia 2007. [DOI: 10.1016/s1634-7072(07)70549-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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de Tommaso M, Shevel E, Pecoraro C, Sardaro M, Losito L, Lamberti P, Livrea P. Topographic analysis of laser evoked potentials in chronic tension-type headache: Correlations with clinical features. Int J Psychophysiol 2006; 62:38-45. [PMID: 16503063 DOI: 10.1016/j.ijpsycho.2005.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 11/28/2005] [Accepted: 12/09/2005] [Indexed: 11/28/2022]
Abstract
In the present study, we examined clinical and laser-evoked potentials (LEP) features in a group of chronic tension-type headache (CTTH) patients, in order to perform a topographic analysis of Laser evoked potentials (LEPs) and a correlation with clinical features. Eighteen patients suffering from CTTH [Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders 2nd ed. Cephalalgia 2004; 24 Suppl 1, 1-159.] participated in the study. Twelve age- and sex-matched controls were also examined. We performed a basal evaluation of clinical features, Total Tenderness Score (TTS) and a topographic analysis of LEPs obtained by the hand and the pericranial points stimulation in all patients vs healthy subjects. The later LEPs, especially the P2 component, were significantly increased in amplitude in the CTTH group, specially when the pericranial points were stimulated. The P2 wave amplitude was correlated with TTS levels and anxiety scores. The results of this study confirm that pericranial tenderness is a phenomenon initiating a self-sustaining circuit, involving central sensitization at the level of the cortical nociceptive areas devoted to attentional and emotional components of pain.
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Affiliation(s)
- Marina de Tommaso
- Neurological and Psychiatric Sciences Department University of Bari, Bari, Italy.
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