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Uglem M, Omland PM, Stjern M, Gravdahl GB, Sand T. Habituation of laser-evoked potentials by migraine phase: a blinded longitudinal study. J Headache Pain 2017; 18:100. [PMID: 28971336 PMCID: PMC5624861 DOI: 10.1186/s10194-017-0810-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022] Open
Abstract
Background Migraineurs seem to have cyclic variations in cortical excitability in several neurophysiological modalities. Laser-evoked potentials (LEP) are of particular interest in migraine because LEP specifically targets pain pathways, and studies have reported different LEP-changes both between and during headaches. Our primary aim was to explore potential cyclic variations in LEP amplitude and habituation in more detail with a blinded longitudinal study design. Methods We compared N1 and N2P2 amplitudes and habituation between two blocks of laser stimulations to the dorsal hand, obtained from 49 migraineurs with four sessions each. We used migraine diaries to categorize sessions as interictal (> one day from previous and to next attack), preictal (< one day before the attack), ictal or postictal (< one day after the attack). Also, we compared 29 interictal recordings from the first session to 30 controls. Results N1 and N2P2 amplitudes and habituation did not differ between preictal, interictal and postictal phase sessions, except for a post hoc contrast that showed deficient ictal habituation of N1. Habituation is present and similar in migraineurs in the interictal phase and controls. Conclusions Hand-evoked LEP amplitudes and habituation were mainly invariable between migraine phases, but this matter needs further study. Because hand-evoked LEP-habituation was similar in migraineurs and controls, the present findings contradict several previous LEP studies. Pain-evoked cerebral responses are normal and show normal habituation in migraine. Electronic supplementary material The online version of this article (10.1186/s10194-017-0810-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martin Uglem
- Department of Neuromedicine and Movement Science, NTNU, Norwegian University of Science and Technology, Trondheim, Norway. .,NTNU, Faculty of Medicine and Health Sciences, P.B. 8905, N-7491, Trondheim, Norway.
| | - Petter Moe Omland
- Department of Neuromedicine and Movement Science, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim, Norway
| | - Marit Stjern
- Department of Neuromedicine and Movement Science, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim, Norway
| | | | - Trond Sand
- Department of Neuromedicine and Movement Science, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim, Norway
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Lisicki M, D'Ostilio K, Erpicum M, Schoenen J, Magis D. Sunlight irradiance and habituation of visual evoked potentials in migraine: The environment makes its mark. Cephalalgia 2017; 38:1351-1360. [PMID: 28856911 DOI: 10.1177/0333102417730128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Background Migraine is a complex multifactorial disease that arises from the interaction between a genetic predisposition and an enabling environment. Habituation is considered as a fundamental adaptive behaviour of the nervous system that is often impaired in migraine populations. Given that migraineurs are hypersensitive to light, and that light deprivation is able to induce functional changes in the visual cortex recognizable through visual evoked potentials habituation testing, we hypothesized that regional sunlight irradiance levels could influence the results of visual evoked potentials habituation studies performed in different locations worldwide. Methods We searched the literature for visual evoked potentials habituation studies comparing healthy volunteers and episodic migraine patients and correlated their results with levels of local solar radiation. Results After reviewing the literature, 26 studies involving 1291 participants matched our inclusion criteria. Deficient visual evoked potentials habituation in episodic migraine patients was reported in 19 studies. Mean yearly sunlight irradiance was significantly higher in locations of studies reporting deficient habituation. Correlation analyses suggested that visual evoked potentials habituation decreases with increasing sunlight irradiance in migraine without aura patients. Conclusion Results from this hypothesis generating analysis suggest that variations in sunlight irradiance may induce adaptive modifications in visual processing systems that could be reflected in visual evoked potentials habituation, and thus partially account for the difference in results between studies performed in geographically distant centers. Other causal factors such as genetic differences could also play a role, and therefore well-designed prospective trials are warranted.
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Affiliation(s)
- Marco Lisicki
- 1 Headache Research Unit, University Department of Neurology CHR, Citadelle Hospital, Liege, Belgium
| | - Kevin D'Ostilio
- 1 Headache Research Unit, University Department of Neurology CHR, Citadelle Hospital, Liege, Belgium
| | - Michel Erpicum
- 2 Climatology and Topoclimatology Laboratory, Faculty of Sciences, Liège University, Liège, Belgium
| | - Jean Schoenen
- 1 Headache Research Unit, University Department of Neurology CHR, Citadelle Hospital, Liege, Belgium
| | - Delphine Magis
- 1 Headache Research Unit, University Department of Neurology CHR, Citadelle Hospital, Liege, Belgium
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Increased Amplitude of Thalamocortical Low-Frequency Oscillations in Patients with Migraine. J Neurosci 2017; 36:8026-36. [PMID: 27466345 DOI: 10.1523/jneurosci.1038-16.2016] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/16/2016] [Indexed: 01/11/2023] Open
Abstract
UNLABELLED For many years, neurobiological theories have emphasized the importance of neuronal oscillations in the emergence of brain function. At the same time, clinical studies have shown that disturbances or irregularities in brain rhythms may relate to various common neurological conditions, including migraine. Increasing evidence suggests that the CNS plays a fundamental role in the predisposition to develop different forms of headache. Here, we present human imaging data that strongly support the presence of abnormal low-frequency oscillations (LFOs) in thalamocortical networks of patients in the interictal phase of migraine. Our results show that the main source of arrhythmic activity was localized to the higher-order thalamic relays of the medial dorsal nucleus. In addition, spontaneous LFOs in the thalamus were selectively associated with the headache attack frequency, meaning that the varying amplitude of dysrhythmia could predispose patients to recurrent attacks. Rhythmic cortical feedback to the thalamus is a major factor in the amplification of thalamocortical oscillations, making it a strong candidate for influencing neuronal excitability. We further speculate that the intrinsic dynamics of thalamocortical network oscillations are crucial for early sensory processing and therefore could underlie important pathophysiological processes involved in multisensory integration. SIGNIFICANCE STATEMENT In many cases, migraine attacks are thought to begin centrally. A major obstacle to studying intrinsic brain activity has been the identification of the precise anatomical structures and functional networks that are involved in migraine. Here, we present imaging data that strongly support the presence of abnormal low-frequency oscillations in thalamocortical networks of patients in the interictal phase of migraine. This arrhythmic activity was localized to the higher-order thalamic relays of the medial dorsal nucleus and was selectively associated with headache attack frequency. Rhythmic cortical feedback to the thalamus is a major factor in the amplification of thalamocortical oscillations, making it a strong candidate for influencing neuronal excitability and higher-level processes involved in multisensory integration.
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El-Shazly AAEF, Farweez YA, Hamdi MM, El-Sherbiny NE. Pattern Visual Evoked Potential, Pattern Electroretinogram, and Retinal Nerve Fiber Layer Thickness in Patients with Migraine during and after Aura. Curr Eye Res 2017. [PMID: 28636408 DOI: 10.1080/02713683.2017.1319490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
PURPOSE To study pattern visual evoked potential (PVEP), pattern electroretinogram (PERG), and retinal nerve fiber layer (RNFL) thickness in patients with migraine during and after aura. MATERIALS AND METHODS We included 60 eyes of 60 patients with migraine (Group 1) and 30 healthy volunteers (30 eyes) as controls (Group 2). Group 1 was studied twice, during a visual aura (1-a) and in between attacks (1-b). All participants underwent full ophthalmological examination, PVEP, PERG, and optical coherence tomographyOCT imaging of the RNFL thickness for each patient. RESULTS RNFL thickness was found to be thinner in patients during the aura compared to controls. It increased significantly post-aura but remained lower than the controls. Prolonged P100 latency and decreased amplitude were found in patients during aura compared to controls with significant change in between attacks to values comparable to the controls. We found prolonged N95 latency and decreased amplitude in patients during aura compared to controls with significant change post-aura to values comparable to the controls. There was positive correlation between average RNFL thicknesses and VA and spherical equivalent; but it showed negative correlation with duration of migraine, attack duration, and aura duration. Multiple regression analysis showed that the most important determinants of average RNFL thickness in patients of migraine were attack and aura duration (beta = -0.21 and -0.26 and p = 0.03 and 0.04, respectively). CONCLUSION Migraine attacks impose both functional and structural retinal changes. The functional changes are fully reversible after the aura but not the structural ones. So, vigorous prevention of migraine attacks would be protective for retina.
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Affiliation(s)
| | - Yousra Ahmed Farweez
- a Department of Ophthalmology, Faculty of Medicine , Ain Shams University , Cairo , Egypt
| | - Momen Mahmoud Hamdi
- a Department of Ophthalmology, Faculty of Medicine , Ain Shams University , Cairo , Egypt
| | - Noha Ezzat El-Sherbiny
- a Department of Ophthalmology, Faculty of Medicine , Ain Shams University , Cairo , Egypt
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55
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Coppola G, Di Renzo A, Tinelli E, Di Lorenzo C, Scapeccia M, Parisi V, Serrao M, Evangelista M, Ambrosini A, Colonnese C, Schoenen J, Pierelli F. Resting state connectivity between default mode network and insula encodes acute migraine headache. Cephalalgia 2017; 38:846-854. [DOI: 10.1177/0333102417715230] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Background Previous functional MRI studies have revealed that ongoing clinical pain in different chronic pain syndromes is directly correlated to the connectivity strength of the resting default mode network (DMN) with the insula. Here, we investigated seed-based resting state DMN-insula connectivity during acute migraine headaches. Methods Thirteen migraine without aura patients (MI) underwent 3 T MRI scans during the initial six hours of a spontaneous migraine attack, and were compared to a group of 19 healthy volunteers (HV). We evaluated headache intensity with a visual analogue scale and collected seed-based MRI resting state data in the four core regions of the DMN: Medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), and left and right inferior parietal lobules (IPLs), as well as in bilateral insula. Results Compared to HV, MI patients showed stronger functional connectivity between MPFC and PCC, and between MPFC and bilateral insula. During migraine attacks, the strength of MPFC-to-insula connectivity was negatively correlated with pain intensity. Conclusion We show that greater subjective intensity of pain during a migraine attack is associated with proportionally weaker DMN-insula connectivity. This is at variance with other chronic extra-cephalic pain disorders where the opposite was found, and may thus be a hallmark of acute migraine head pain.
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Affiliation(s)
- Gianluca Coppola
- G.B. Bietti Foundation IRCCS, Research Unit of Neurophysiology of Vision and Neurophthalmology, Rome, Italy
| | - Antonio Di Renzo
- G.B. Bietti Foundation IRCCS, Research Unit of Neurophysiology of Vision and Neurophthalmology, Rome, Italy
| | - Emanuele Tinelli
- “Sapienza” University of Rome, Department of Neurology and Psychiatry, Neuroradiology section, Rome, Italy
| | | | - Marco Scapeccia
- “Sapienza” University of Rome, Department of Neurology and Psychiatry, Neuroradiology section, Rome, Italy
| | - Vincenzo Parisi
- G.B. Bietti Foundation IRCCS, Research Unit of Neurophysiology of Vision and Neurophthalmology, Rome, Italy
| | - Mariano Serrao
- “Sapienza” University of Rome Polo Pontino, Department of Medico-surgical Sciences and Biotechnologies, Latina, Italy
| | - Maurizio Evangelista
- Università Cattolica del Sacro Cuore/CIC, Istituto di Anestesiologia, Rianimazione e Terapia del Dolore, Rome, Italy
| | | | - Claudio Colonnese
- “Sapienza” University of Rome, Department of Neurology and Psychiatry, Neuroradiology section, Rome, Italy
- IRCCS Neuromed, Pozzilli (IS), Italy
| | - Jean Schoenen
- Headache Research Unit, Department of Neurology-CHR Citadelle, University of Liège, Belgium
| | - Francesco Pierelli
- “Sapienza” University of Rome Polo Pontino, Department of Medico-surgical Sciences and Biotechnologies, Latina, Italy
- IRCCS Neuromed, Pozzilli (IS), Italy
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Ince F, Erdogan-Bakar E, Unal-Cevik I. Preventive drugs restore visual evoked habituation and attention in migraineurs. Acta Neurol Belg 2017; 117:523-530. [PMID: 28150096 DOI: 10.1007/s13760-017-0749-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/17/2017] [Indexed: 01/03/2023]
Abstract
Visual system pathway dysfunction has been postulated in migraineurs. We wanted to investigate if any difference exists interictally in visual attention and visual evoked habituation of frequently attacked migraineurs compared to the healthy control group. The effects of 3-month prophylactic migraine treatment on these parameters were also assessed. The migraineurs at headache-free interval (n = 52) and age, sex-matched healthy controls (n = 35) were compared by habituation response to 10 blocks of repetitive pattern-reversal visual stimuli (each block consisted 100 responses). The amplitude changes of 5th and 10th blocks were further compared with that of block 1 to assess the response of habituation (i.e., decrease) or potentiation (i.e., increase). The level of sustained visual attention was assessed by Cancellation test. Migraineurs were randomized to three different preventive treatments: propranolol 40 mg tid, flunarizine 5 mg bid, or topiramate 50 mg bid. After 3 months of preventive treatment, migraineurs data were compared with their baseline values. The groups did not differ by sex and age. In electrophysiological studies, the habituation ability observed in the healthy group was not observed in migraineurs. However, it was restored 3 months after preventive treatment. In migraineurs, compared to their baseline values, the distorted visual attention parameters also improved after treatment. All drugs were effective. The loss of habituation ability and low visual attention performance in migraineurs can be restored by migraine preventive treatment. This electrophysiological study accompanied by neuropsychological test may aid an objective and quantitative assessment tool for understanding migraine pathophysiology.
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Affiliation(s)
- Ferda Ince
- Department of Neurology, Ozel Ilke Yasam Medical Center, Dortyol, Turkey
| | - Emel Erdogan-Bakar
- Department of Psychology, Faculty of Science and Letter, Ufuk University, Ankara, Turkey
| | - Isin Unal-Cevik
- Department of Neurology, Faculty of Medicine, Pain Unit, Hacettepe University, Sıhhiye, 06100, Ankara, Turkey.
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McDiarmid TA, Bernardos AC, Rankin CH. Habituation is altered in neuropsychiatric disorders-A comprehensive review with recommendations for experimental design and analysis. Neurosci Biobehav Rev 2017; 80:286-305. [PMID: 28579490 DOI: 10.1016/j.neubiorev.2017.05.028] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 05/29/2017] [Indexed: 02/03/2023]
Abstract
Abnormalities in the simplest form of learning, habituation, have been reported in a variety of neuropsychiatric disorders as etiologically diverse as Autism Spectrum Disorder, Fragile X syndrome, Schizophrenia, Parkinson's Disease, Huntington's Disease, Attention Deficit Hyperactivity Disorder, Tourette's Syndrome, and Migraine. Here we provide the first comprehensive review of what is known about alterations in this form of non-associative learning in each disorder. Across several disorders, abnormal habituation is predictive of symptom severity, highlighting the clinical significance of habituation and its importance to normal cognitive function. Abnormal habituation is discussed within the greater framework of learning theory and how it may relate to disease phenotype either as a cause, symptom, or therapy. Important considerations for the design and interpretation of habituation experiments are outlined with the hope that these will aid both clinicians and basic researchers investigating how this simple form of learning is altered in disease.
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Affiliation(s)
- Troy A McDiarmid
- Graduate Program in Neuroscience, University of British Columbia, 2215 Wesbrook Mall, Vancouver, British Columbia, V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Rm F221, 2211 Wesbrook Mall, Vancouver, British Columbia, V6T 2B5, Canada
| | - Aram C Bernardos
- Graduate Program in Neuroscience, University of British Columbia, 2215 Wesbrook Mall, Vancouver, British Columbia, V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Rm F221, 2211 Wesbrook Mall, Vancouver, British Columbia, V6T 2B5, Canada
| | - Catharine H Rankin
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, V6T 1Z4, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Rm F221, 2211 Wesbrook Mall, Vancouver, British Columbia, V6T 2B5, Canada.
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Cortese F, Coppola G, Di Lenola D, Serrao M, Di Lorenzo C, Parisi V, Pierelli F. Excitability of the motor cortex in patients with migraine changes with the time elapsed from the last attack. J Headache Pain 2017; 18:2. [PMID: 28063106 PMCID: PMC5218956 DOI: 10.1186/s10194-016-0712-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 12/09/2016] [Indexed: 12/03/2022] Open
Abstract
Background Motor-evoked potentials (MEPs) produced by single-pulse transcranial magnetic stimulation (TMS) of the motor cortex can be an objective measure of cortical excitability. Previously, MEP thresholds were found to be normal, increased, or even reduced in patients with migraine. In the present study, we determined whether the level of cortical excitability changes with the time interval from the last migraine attack, thereby accounting for the inconsistencies in previous reports. Methods Twenty-six patients with untreated migraine without aura (MO) underwent a MEP study between attacks. Their data were then compared to the MEP data collected from a group of 24 healthy volunteers (HVs). During the experiment, the TMS figure-of-eight coil was positioned over the left motor area. After identifying the resting motor threshold (RMT), we delivered 10 single TMS pulses (rate: 0.1 Hz, intensity: 120% of the RMT) and averaged the resulting MEP amplitudes. Results The mean RMTs and MEP amplitudes were not significantly different between the MO and HV groups. In patients with MO, the RMTs were negatively correlated with the number of days elapsed since the last migraine attack (rho = -0.404, p = 0.04). Conclusion Our results suggest that the threshold for evoking MEPs is influenced by the proximity of an attack; specifically, the threshold is lower when a long time interval has passed after an attack, and is higher (within the range of normative values) when measured close to an attack. These dynamic RMT variations resemble those we reported previously for visual and somatosensory evoked potentials and may represent time-dependent plastic changes in brain excitability in relation to the migraine cycle.
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Affiliation(s)
- Francesca Cortese
- Department of Medico-Surgical Sciences and Biotechnologies, 'Sapienza' University of Rome Polo Pontino, Corso della Repubblica 79, 04100, Latina, Italy.
| | - Gianluca Coppola
- G. B. Bietti Foundation IRCCS, Research Unit of Neurophysiology of Vision and Neuro-Ophthalmology, Rome, Italy
| | - Davide Di Lenola
- Department of Medico-Surgical Sciences and Biotechnologies, 'Sapienza' University of Rome Polo Pontino, Corso della Repubblica 79, 04100, Latina, Italy
| | - Mariano Serrao
- Department of Medico-Surgical Sciences and Biotechnologies, 'Sapienza' University of Rome Polo Pontino, Corso della Repubblica 79, 04100, Latina, Italy
| | | | - Vincenzo Parisi
- G. B. Bietti Foundation IRCCS, Research Unit of Neurophysiology of Vision and Neuro-Ophthalmology, Rome, Italy
| | - Francesco Pierelli
- Department of Medico-Surgical Sciences and Biotechnologies, 'Sapienza' University of Rome Polo Pontino, Corso della Repubblica 79, 04100, Latina, Italy.,INM Neuromed IRCCS, Pozzilli, (IS), Italy
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Alice in Wonderland Syndrome: A Clinical and Pathophysiological Review. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8243145. [PMID: 28116304 PMCID: PMC5223006 DOI: 10.1155/2016/8243145] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 11/20/2016] [Indexed: 01/09/2023]
Abstract
Alice in Wonderland Syndrome (AIWS) is a perceptual disorder, principally involving visual and somesthetic integration, firstly reported by Todd, on the literary suggestion of the strange experiences described by Lewis Carroll in Alice in Wonderland books. Symptoms may comprise among others aschematia and dysmetropsia. This syndrome has many different etiologies; however EBV infection is the most common cause in children, while migraine affects more commonly adults. Many data support a strict relationship between migraine and AIWS, which could be considered in many patients as an aura or a migraine equivalent, particularly in children. Nevertheless, AIWS seems to have anatomical correlates. According to neuroimaging, temporoparietal-occipital carrefour (TPO-C) is a key region for developing many of AIWS symptoms. The final part of this review aims to find the relationship between AIWS symptoms, presenting a pathophysiological model. In brief, AIWS symptoms depend on an alteration of TPO-C where visual-spatial and somatosensory information are integrated. Alterations in these brain regions may cause the cooccurrence of dysmetropsia and disorders of body schema. In our opinion, the association of other symptoms reported in literature could vary depending on different etiologies and the lack of clear diagnostic criteria.
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Ambrosini A, Kisialiou A, Coppola G, Finos L, Magis D, Pierelli F, Schoenen J. Visual and auditory cortical evoked potentials in interictal episodic migraine: An audit on 624 patients from three centres. Cephalalgia 2016; 37:1126-1134. [DOI: 10.1177/0333102416665224] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Many studies report a habituation deficit of visual evoked potentials (VEP) and/or increased intensity dependence of auditory evoked cortical potentials (IDAP) in episodic migraine patients between attacks. These findings have a pathophysiological interest, but their diagnostic utility is not known. Aims To perform an audit on a large database of interictal VEP and IDAP recordings in episodic migraine patients and evaluate their diagnostic accuracy. Methods We pooled data for VEP habituation and IDAP measured in 624 episodic migraineurs (EM) and 360 healthy volunteers (HV) from three centers. Thresholds were calculated by Receiver Operating Curve analysis and used to calculate sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-) and the accuracy of each test, using ICHD diagnostic criteria as the gold standard. Results In EM, VEP habituation was significantly lower than in HV, and IDAP slopes were significantly steeper. VEP (five blocks of 50 responses), VEP (six blocks of 100 responses) and IDAP had respectively 61.0%, 61.4% and 45.7% sensitivity, and 77.9%, 77.9% and 87.2% specificity. Their positive (LR+) and negative (LR-) likelihood ratios were respectively 2.760, 2.778, 3.570 and 0.500, 0.495, 0.623, with diagnostic accuracies of 65.3%, 69.0% and 54.3%. In combined VEP + IDAP recordings, an abnormality of at least one test had 83.4% sensitivity, 66.7% specificity, 2.504 LR+, 0.249 LR− and 81.1% accuracy. Conclusions In this large database, VEP habituation is significantly reduced and IDAP increased in episodic migraine patients between attacks. Taken alone, neither VEP nor IDAP has sufficient diagnostic accuracy. However, when both tests are performed in the same patient, an abnormality of at least one of them is highly predictive of interictal episodic migraine.
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Affiliation(s)
| | - Aliaksei Kisialiou
- Clinical and Molecular Epidemiology Unit, IRCCS San Raffaele Pisana, Rome, Italy
| | - Gianluca Coppola
- Department of Neurophysiology of Vision and Neurophthalmology, GB Bietti Foundation IRCCS, Rome, Italy
| | - Livio Finos
- Department of Developmental Psychology and Socialization, University of Padua, Italy
| | | | - Francesco Pierelli
- Headache Unit, IRCCS Neuromed, Pozzilli, IS, Italy
- Sapienza University of Rome Polo Pontino, Department of Medico-Surgical Sciences and Biotechnologies, Latina, Italy
| | - Jean Schoenen
- Headache Research Unit, University Dept of Neurology, Citadelle Hospital, Liège, Belgium
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Li F, Xiang J, Wu T, Zhu D, Shi J. Abnormal resting-state brain activity in headache-free migraine patients: A magnetoencephalography study. Clin Neurophysiol 2016; 127:2855-2861. [PMID: 27417062 DOI: 10.1016/j.clinph.2016.05.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/02/2016] [Accepted: 05/19/2016] [Indexed: 01/17/2023]
Abstract
OBJECTIVE The aim of this study is to quantitatively assess the resting-state brain activity in migraine patients during the headache-free phase with magnetoencephalography (MEG). METHODS A total of 25 migraine patients during the headache-free phase and 25 gender- and age-matched control patients were studied with a whole-head MEG system at eyes-closed resting-state. MEG data were analyzed in multifrequency range of 4-200Hz. RESULTS In a regional cortex analysis, the spectral power of gamma oscillations in left frontal and left temporal regions was significantly increased in migraine patients as compared to controls (all p<0.001), but no significant difference was found between the two groups for the global channels. Analyses of source location showed that there were significant differences in the distribution of gamma oscillation between migraine subjects and controls (p<0.025). CONCLUSIONS Migraine patients in resting-state had altered brain activities in spectral power value and source distribution that can be detected and analyzed by MEG. SIGNIFICANCE Abnormal brain activities in the left frontal and temporal regions may be involved in pain modulation and processing of migraine. These findings provide new insights into the possible mechanisms of migraine attacks.
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Affiliation(s)
- Feng Li
- Department of Neurology, Nanjing Brain Hospital, Nanjing Medical University, Jiangsu, People's Republic of China
| | - Jing Xiang
- Department of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Ting Wu
- The MEG Center, Nanjing Brain Hospital, Nanjing, Jiangsu, People's Republic of China
| | - Donglin Zhu
- Department of Neurology, Nanjing Brain Hospital, Nanjing Medical University, Jiangsu, People's Republic of China
| | - Jingping Shi
- Department of Neurology, Nanjing Brain Hospital, Nanjing Medical University, Jiangsu, People's Republic of China; Department of Neurology, School of Medicine, Nanjing University, No. 22 Hankou Road, Nanjing 210093, People's Republic of China.
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Omland PM, Uglem M, Hagen K, Linde M, Tronvik E, Sand T. Visual evoked potentials in migraine: Is the “neurophysiological hallmark” concept still valid? Clin Neurophysiol 2016; 127:810-816. [DOI: 10.1016/j.clinph.2014.12.035] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Revised: 12/15/2014] [Accepted: 12/28/2014] [Indexed: 01/03/2023]
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63
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Borkum JM. Migraine Triggers and Oxidative Stress: A Narrative Review and Synthesis. Headache 2015; 56:12-35. [PMID: 26639834 DOI: 10.1111/head.12725] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND Blau theorized that migraine triggers are exposures that in higher amounts would damage the brain. The recent discovery that the TRPA1 ion channel transduces oxidative stress and triggers neurogenic inflammation suggests that oxidative stress may be the common denominator underlying migraine triggers. OBJECTIVE The aim of this review is to present and discuss the available literature on the capacity of common migraine triggers to generate oxidative stress in the brain. METHODS A Medline search was conducted crossing the terms "oxidative stress" and "brain" with "alcohol," "dehydration," "water deprivation," "monosodium glutamate," "aspartame," "tyramine," "phenylethylamine," "dietary nitrates," "nitrosamines," "noise," "weather," "air pollutants," "hypoglycemia," "hypoxia," "infection," "estrogen," "circadian," "sleep deprivation," "information processing," "psychosocial stress," or "nitroglycerin and tolerance." "Flavonoids" was crossed with "prooxidant." The reference lists of the resulting articles were examined for further relevant studies. The focus was on empirical studies, in vitro and of animals, of individual triggers, indicating whether and/or by what mechanism they can generate oxidative stress. RESULTS In all cases except pericranial pain, common migraine triggers are capable of generating oxidative stress. Depending on the trigger, mechanisms include a high rate of energy production by the mitochondria, toxicity or altered membrane properties of the mitochondria, calcium overload and excitotoxicity, neuroinflammation and activation of microglia, and activation of neuronal nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. For some triggers, oxidants also arise as a byproduct of monoamine oxidase or cytochrome P450 processing, or from uncoupling of nitric oxide synthase. CONCLUSIONS Oxidative stress is a plausible unifying principle behind the types of migraine triggers encountered in clinical practice. The possible implications for prevention and for understanding the nature of the migraine attack are discussed.
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Affiliation(s)
- Jonathan M Borkum
- Department of Psychology, University of Maine, Orono, ME, USA.,Health Psych Maine, Waterville, ME, USA
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Coppola G, Bracaglia M, Di Lenola D, Di Lorenzo C, Serrao M, Parisi V, Di Renzo A, Martelli F, Fadda A, Schoenen J, Pierelli F. Visual evoked potentials in subgroups of migraine with aura patients. J Headache Pain 2015; 16:92. [PMID: 26527348 PMCID: PMC4630240 DOI: 10.1186/s10194-015-0577-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 09/15/2015] [Indexed: 01/06/2023] Open
Abstract
Background Patients suffering from migraine with aura can have either pure visual auras or complex auras with sensory disturbances and dysphasia, or both. Few studies have searched for possible pathophysiological differences between these two subgroups of patients. Methods Methods - Forty-seven migraine with aura patients were subdivided in a subgroup with exclusively visual auras (MA, N = 27) and another with complex neurological auras (MA+, N = 20). We recorded pattern-reversal visual evoked potentials (VEP: 15 min of arc cheques, 3.1 reversal per second, 600 sweeps) and measured amplitude and habituation (slope of the linear regression line of amplitude changes from the 1st to 6th block of 100 sweeps) for the N1-P1 and P1-N2 components in patients and, for comparison, in 30 healthy volunteers (HV) of similar age and gender distribution. Results VEP N1-P1 habituation, i.e. amplitude decrement between 1st and 6th block, which was obvious in most HV (mean slope −0.50), was deficient in both MA (slope +0.01, p = 0.0001) and MA+ (−0.0049, p = 0.001) patients. However, VEP N1-P1 amplitudes across blocks were normal in MA patients, while they were significantly greater in MA+ patients than in HVs. Conclusions Our findings suggest that in migraine with aura patients different aura phenotypes may be underpinned by different pathophysiological mechanisms. Pre-activation cortical excitability could be higher in patients with complex neurological auras than in those having pure visual auras or in healthy volunteers.
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Affiliation(s)
- Gianluca Coppola
- G.B. Bietti Foundation-IRCCS, Department of Neurophysiology of Vision and Neurophthalmology, Via Livenza 3, 00198, Rome, Italy.
| | - Martina Bracaglia
- Department of Medical and Surgical Sciences and Biotechnologies, "Sapienza" University of Rome Polo Pontino, Latina, Italy
| | - Davide Di Lenola
- Department of Medical and Surgical Sciences and Biotechnologies, "Sapienza" University of Rome Polo Pontino, Latina, Italy
| | | | - Mariano Serrao
- Department of Medical and Surgical Sciences and Biotechnologies, "Sapienza" University of Rome Polo Pontino, Latina, Italy
| | - Vincenzo Parisi
- G.B. Bietti Foundation-IRCCS, Department of Neurophysiology of Vision and Neurophthalmology, Via Livenza 3, 00198, Rome, Italy
| | - Antonio Di Renzo
- G.B. Bietti Foundation-IRCCS, Department of Neurophysiology of Vision and Neurophthalmology, Via Livenza 3, 00198, Rome, Italy
| | - Francesco Martelli
- Istituto Superiore di Sanità, Dipartimento Tecnologie e Salute, Rome, Italy
| | - Antonello Fadda
- Istituto Superiore di Sanità, Dipartimento Tecnologie e Salute, Rome, Italy
| | - Jean Schoenen
- Headache Research Unit, Department of Neurology-CHR Citadelle, University of Liège, Liège, Belgium
| | - Francesco Pierelli
- Department of Medical and Surgical Sciences and Biotechnologies, "Sapienza" University of Rome Polo Pontino, Latina, Italy.,IRCCS-Neuromed, Pozzilli, IS, Italy
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Coppola G, Bracaglia M, Di Lenola D, Iacovelli E, Di Lorenzo C, Serrao M, Evangelista M, Parisi V, Schoenen J, Pierelli F. Lateral inhibition in the somatosensory cortex during and between migraine without aura attacks: Correlations with thalamocortical activity and clinical features. Cephalalgia 2015; 36:568-78. [DOI: 10.1177/0333102415610873] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 08/09/2015] [Indexed: 12/23/2022]
Abstract
Background We studied lateral inhibition in the somatosensory cortex of migraineurs during and between attacks, and searched for correlations with thalamocortical activity and clinical features. Participants and methods Somatosensory evoked potentials (SSEP) were obtained by electrical stimulation of the right median (M) or ulnar (U) nerves at the wrist or by simultaneous stimulation of both nerves (MU) in 41 migraine without aura patients, 24 between (MO), 17 during attacks, and in 17 healthy volunteers (HVs). We determined the percentage of lateral inhibition of the N20–P25 component by using the formula [(100)–MU/(M + U)*100]. We also studied high-frequency oscillations (HFOs) reflecting thalamocortical activation. Results In migraine, both lateral inhibition (MO 27.9% vs HVs 40.2%; p = 0.009) and thalamocortical activity (MO 0.5 vs HVs 0.7; p = 0.02) were reduced between attacks, but not during. In MO patients, the percentage of lateral inhibition negatively correlated with days elapsed since the last migraine attack ( r = −0.510, p = 0.01), monthly attack duration ( r = −0.469, p = 0.02) and severity ( r = −0.443, p = 0.03), but positively with thalamocortical activity ( r = −0.463, p = 0.02). Conclusions We hypothesize that abnormal migraine cycle-dependent dynamics of connectivity between subcortical and cortical excitation/inhibition networks may contribute to clinical features of MO and recurrence of attacks.
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Affiliation(s)
- Gianluca Coppola
- G.B. Bietti Foundation-IRCCS, Department of Neurophysiology of Vision and Neurophthalmology, Rome, Italy
| | - Martina Bracaglia
- “Sapienza” University of Rome Polo Pontino Department of Medical and Surgical Sciences and Biotechnologies, Italy
| | - Davide Di Lenola
- “Sapienza” University of Rome Polo Pontino Department of Medical and Surgical Sciences and Biotechnologies, Italy
| | - Elisa Iacovelli
- “Sapienza” University of Rome Polo Pontino Department of Medical and Surgical Sciences and Biotechnologies, Italy
| | | | - Mariano Serrao
- “Sapienza” University of Rome Polo Pontino Department of Medical and Surgical Sciences and Biotechnologies, Italy
| | - Maurizio Evangelista
- Istituto di Anestesiologia, Rianimazione e Terapia del Dolore, Università Cattolica del Sacro Cuore/CIC, Italy
| | - Vincenzo Parisi
- G.B. Bietti Foundation-IRCCS, Department of Neurophysiology of Vision and Neurophthalmology, Rome, Italy
| | - Jean Schoenen
- Headache Research Unit, Department of Neurology-CHR Citadelle, University of Liège, Belgium
| | - Francesco Pierelli
- “Sapienza” University of Rome Polo Pontino Department of Medical and Surgical Sciences and Biotechnologies, Italy
- INM Neuromed IRCCS, Italy
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Demarquay G, Mauguière F. Central Nervous System Underpinnings of Sensory Hypersensitivity in Migraine: Insights from Neuroimaging and Electrophysiological Studies. Headache 2015; 56:1418-1438. [PMID: 26350583 DOI: 10.1111/head.12651] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2015] [Indexed: 01/03/2023]
Abstract
Whereas considerable data have been generated about the pathophysiology of pain processing during migraine attacks, relatively little is known about the neural basis of sensory hypersensitivity. In migraine, the term "hypersensitivity" encompasses different and probably distinct pathophysiological aspects of sensory sensitivity. During attacks, many patients have enhanced sensitivity to visual, auditory and/or olfactory stimuli, which can enhance headache while interictally, migraineurs often report abnormal sensitivity to environmental stimuli that can cause nonpainful discomfort. In addition, sensorial stimuli can influence and trigger the onset of migraine attacks. The pathophysiological mechanisms and the origin of such sensitivity (individual predisposition to develop migraine disease or consequence of repeated migraine attacks) are ill understood. Functional neuroimaging and electrophysiological studies allow for noninvasive measures of neuronal responses to external stimuli and have contributed to our understanding of mechanisms underlying sensory hypersensitivity in migraine. The purpose of this review is to present pivotal neuroimaging and neurophysiological studies that explored the basal state of brain responsiveness to sensory stimuli in migraineurs, the alterations in habituation and attention to sensory inputs, the fluctuations of responsiveness to sensory stimuli before and during migraine attacks, and the relations between sensory hypersensitivity and clinical sensory complaints.
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Affiliation(s)
- Geneviève Demarquay
- Department of Neurology, Croix-Rousse Hospital, Hospices Civils de Lyon, Lyon, France and Lyon Neuroscience Research Center (CRNL), Brain Dynamics and Cognition Team (Dycog), INSERM U1028, CNRS UMR5292, Lyon, France.
| | - François Mauguière
- Neurological Hospital Pierre Wertheimer: Functional Neurology and Epilepsy Department, Hospices Civils de Lyon and Claude Bernard Lyon1 University, Lyon, France, and Lyon Neuroscience Research Center (CRNL), Neuropain team, INSERM U1028, CNRS UMR5292, Lyon, France
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Ambrosini A, Iezzi E, Perrotta A, Kisialiou A, Nardella A, Berardelli A, Pierelli F, Schoenen J. Correlation between habituation of visual-evoked potentials and magnetophosphene thresholds in migraine: A case-control study. Cephalalgia 2015; 36:258-64. [DOI: 10.1177/0333102415590241] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 04/25/2015] [Indexed: 01/03/2023]
Abstract
Introduction In migraine most studies report an interictal deficit of habituation of visual-evoked potentials (VEP-hab) and reduced thresholds for phosphene induction (PT) by transcranial magnetic stimulation (TMS). We searched for a possible correlation between VEP-hab and PT in migraine patients and healthy controls to test whether they reflect the same pathophysiological abnormality. Methods We assessed PT and VEP-hab measured as the percentage change of N1/P1 amplitude over six blocks of 100 responses in 15 healthy volunteers (HV) and in 13 episodic migraineurs without aura (MO) between attacks. Results were compared using Mann-Whitney U test. Interrelationships were examined using Spearman's correlation. Results In MO patients VEP-hab was reduced compared to HV ( p = 0.001), while PT were not significantly different between HV and MO. There was no correlation between PT and VEP-hab in either group of participants. Conclusions We confirm that in interictal migraine VEP habituation is deficient, but magnetophosphene threshold normal. VEP-hab and PT were not correlated with each other in healthy controls or in migraineurs. This finding suggests that they index different facets of cortical excitability in migraine, i.e. a punctual normal measure of the cortical activation threshold for PT and a dynamic response pattern to repeated stimuli for VEP habituation.
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Affiliation(s)
| | - Ennio Iezzi
- IRCCS Neuromed, Clinical Neurophysiology Unit, Italy
| | | | - Aliaksei Kisialiou
- IRCCS San Raffaele Pisana, Unit of Clinical and Molecular Epidemiology, Italy
| | | | - Alfredo Berardelli
- IRCCS Neuromed, Clinical Neurophysiology Unit, Italy
- Sapienza University of Rome, Department of Neurology and Psychiatry, Italy
| | - Francesco Pierelli
- IRCCS Neuromed, Headache Unit, Italy
- Sapienza University of Rome, Department of Medical-Surgical Sciences and Biotechnologies, Italy
| | - Jean Schoenen
- University of Liège – CHR Citadelle, University Dept. of Neurology, Headache Research Unit, Belgium
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Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society. Acta Neurol Belg 2015; 115:1-17. [PMID: 24968722 DOI: 10.1007/s13760-014-0313-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 05/13/2014] [Indexed: 12/24/2022]
Abstract
Chronic migraine (CM) is a disabling neurological condition affecting 0.5-2 % of the population. In the current third edition of the International Classification of Headache Disorders, medication overuse is no longer an exclusion criterion and CM is diagnosed in patients suffering from at least 15 headache days per month of which at least eight are related to migraine. CM is difficult to treat, and preventive treatment options are limited. We provide a pathogenetic model for CM, integrating the latest findings from neurophysiological and neuroimaging studies. On behalf of the Belgian Headache Society, we present a management algorithm for CM based on the international literature and adapted to the Belgian situation. Pharmacological treatment options are discussed, and recent data on transcranial and invasive neuromodulation studies in CM are reviewed. An integrated multimodal treatment programme may be beneficial to refractory patients, but at present, this approach is only supported by a limited number of observational studies and quite variable between centres.
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Abstract
Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly used in neurology. Transcutaneous supraorbital nerve stimulation is effective in episodic migraine prevention, whereas vagus nerve stimulation provides interesting results in acute migraine therapy. Transcranial stimulation techniques gave variable, and sometimes contradictory, results. The visual cortex is the target of choice in migraine: studies in migraine prevention and aura acute treatment are encouraging. These noninvasive therapies appear safe with a low rate of side effects. Available studies of invasive occipital nerve stimulation in chronic migraine gave modest results; but invasive occipital nerve stimulation offers a new hope to highly disabled patients who failed to respond to any other treatment. In the future, neuromodulation will probably take an increasing place in migraine treatment, as add-on therapy or alternative to medications, especially because of its attractive safety profile.
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Affiliation(s)
- Delphine Magis
- Headache Research Unit, University Department of Neurology CHR Citadelle, Boulevard du 12ème de Ligne 1, 4000 Liège, Belgium
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Cosentino G, Fierro B, Brighina F. From different neurophysiological methods to conflicting pathophysiological views in migraine: A critical review of literature. Clin Neurophysiol 2014; 125:1721-30. [DOI: 10.1016/j.clinph.2014.05.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 04/17/2014] [Accepted: 05/05/2014] [Indexed: 01/15/2023]
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Abstract
Migraine is a very prevalent disease with great individual disability and socioeconomic burden. Despite intensive research effort in recent years, the etiopathogenesis of the disease remains to be elucidated. Recently, much importance has been given to mechanisms underlying the cortical excitability that has been suggested to be dysfunctional in migraine. In recent years, noninvasive brain stimulation techniques based on magnetic fields (transcranial magnetic stimulation, TMS) and on direct electrical currents (transcranial direct current stimulation, tDCS) have been shown to be safe and effective tools to explore the issue of cortical excitability, activation, and plasticity in migraine. Moreover, TMS, repetitive TMS (rTMS), and tDCS, thanks to their ability to interfere with and/or modulate cortical activity inducing plastic, persistent effects, have been also explored as potential therapeutic approaches, opening an interesting perspective for noninvasive neurostimulation for both symptomatic and preventive treatment of migraine and other types of headache. In this chapter we critically review evidence regarding the role of noninvasive brain stimulation in the pathophysiology and treatment of migraine, delineating the advantages and limits of these techniques together with potential development and future application.
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Granziera C, Daducci A, Romascano D, Roche A, Helms G, Krueger G, Hadjikhani N. Structural abnormalities in the thalamus of migraineurs with aura: a multiparametric study at 3 T. Hum Brain Mapp 2014; 35:1461-8. [PMID: 23450507 PMCID: PMC6869319 DOI: 10.1002/hbm.22266] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 11/27/2012] [Accepted: 01/03/2013] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND OBJECTIVES The thalamus exerts a pivotal role in pain processing and cortical excitability control, and migraine is characterized by repeated pain attacks and abnormal cortical habituation to excitatory stimuli. This work aimed at studying the microstructure of the thalamus in migraine patients using an innovative multiparametric approach at high-field magnetic resonance imaging (MRI). DESIGN We examined 37 migraineurs (22 without aura, MWoA, and 15 with aura, MWA) as well as 20 healthy controls (HC) in a 3-T MRI equipped with a 32-channel coil. We acquired whole-brain T1 relaxation maps and computed magnetization transfer ratio (MTR), generalized fractional anisotropy, and T2* maps to probe microstructural and connectivity integrity and to assess iron deposition. We also correlated the obtained parametric values with the average monthly frequency of migraine attacks and disease duration. RESULTS T1 relaxation time was significantly shorter in the thalamus of MWA patients compared with MWoA (P < 0.001) and HC (P ≤ 0.01); in addition, MTR was higher and T2* relaxation time was shorter in MWA than in MWoA patients (P < 0.05, respectively). These data reveal broad microstructural alterations in the thalamus of MWA patients compared with MWoA and HC, suggesting increased iron deposition and myelin content/cellularity. However, MWA and MWoA patients did not show any differences in the thalamic nucleus involved in pain processing in migraine. CONCLUSIONS There are broad microstructural alterations in the thalamus of MWA patients that may underlie abnormal cortical excitability control leading to cortical spreading depression and visual aura.
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Affiliation(s)
- Cristina Granziera
- GRHAD, BMI, SV, EPFL, Lausanne, Switzerland; Laboratoire de Recherche en Neuroimagerie and Neuroimmunology Unit, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Advanced Clinical Imaging Technology Group, Siemens-CIBM, EPFL, Lausanne, Switzerland
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Arakaki X, Galbraith G, Pikov V, Fonteh AN, Harrington MG. Altered brainstem auditory evoked potentials in a rat central sensitization model are similar to those in migraine. Brain Res 2014; 1563:110-21. [PMID: 24680742 DOI: 10.1016/j.brainres.2014.03.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/26/2014] [Accepted: 03/20/2014] [Indexed: 01/04/2023]
Abstract
Migraine symptoms often include auditory discomfort. Nitroglycerin (NTG)-triggered central sensitization (CS) provides a rodent model of migraine, but auditory brainstem pathways have not yet been studied in this example. Our objective was to examine brainstem auditory evoked potentials (BAEPs) in rat CS as a measure of possible auditory abnormalities. We used four subdermal electrodes to record horizontal (h) and vertical (v) dipole channel BAEPs before and after injection of NTG or saline. We measured the peak latencies (PLs), interpeak latencies (IPLs), and amplitudes for detectable waveforms evoked by 8, 16, or 32 kHz auditory stimulation. At 8 kHz stimulation, vertical channel positive PLs of waves 4, 5, and 6 (vP4, vP5, and vP6), and related IPLs from earlier negative or positive peaks (vN1-vP4, vN1-vP5, vN1-vP6; vP3-vP4, vP3-vP6) increased significantly 2h after NTG injection compared to the saline group. However, BAEP peak amplitudes at all frequencies, PLs and IPLs from the horizontal channel at all frequencies, and the vertical channel stimulated at 16 and 32 kHz showed no significant/consistent change. For the first time in the rat CS model, we show that BAEP PLs and IPLs ranging from putative bilateral medial superior olivary nuclei (P4) to the more rostral structures such as the medial geniculate body (P6) were prolonged 2h after NTG administration. These BAEP alterations could reflect changes in neurotransmitters and/or hypoperfusion in the midbrain. The similarity of our results with previous human studies further validates the rodent CS model for future migraine research.
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Affiliation(s)
- Xianghong Arakaki
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 North El Molino Avenue, Pasadena, CA 91101, USA.
| | - Gary Galbraith
- Mental Retardation Research Center, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, USA
| | - Victor Pikov
- Neural Engineering Program, Huntington Medical Research Institutes, 734 Fair mount Avenue, Pasadena, CA 91101, USA
| | - Alfred N Fonteh
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 North El Molino Avenue, Pasadena, CA 91101, USA
| | - Michael G Harrington
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 North El Molino Avenue, Pasadena, CA 91101, USA.
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de Tommaso M, Ambrosini A, Brighina F, Coppola G, Perrotta A, Pierelli F, Sandrini G, Valeriani M, Marinazzo D, Stramaglia S, Schoenen J. Altered processing of sensory stimuli in patients with migraine. Nat Rev Neurol 2014; 10:144-55. [PMID: 24535465 DOI: 10.1038/nrneurol.2014.14] [Citation(s) in RCA: 212] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Migraine is a cyclic disorder, in which functional and morphological brain changes fluctuate over time, culminating periodically in an attack. In the migrainous brain, temporal processing of external stimuli and sequential recruitment of neuronal networks are often dysfunctional. These changes reflect complex CNS dysfunction patterns. Assessment of multimodal evoked potentials and nociceptive reflex responses can reveal altered patterns of the brain's electrophysiological activity, thereby aiding our understanding of the pathophysiology of migraine. In this Review, we summarize the most important findings on temporal processing of evoked and reflex responses in migraine. Considering these data, we propose that thalamocortical dysrhythmia may be responsible for the altered synchronicity in migraine. To test this hypothesis in future research, electrophysiological recordings should be combined with neuroimaging studies so that the temporal patterns of sensory processing in patients with migraine can be correlated with the accompanying anatomical and functional changes.
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Affiliation(s)
| | - Anna Ambrosini
- Headache Clinic, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, Via Atinense 18, Pozzilli, 86077 Isernia, Italy
| | | | | | - Armando Perrotta
- Headache Clinic, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, Via Atinense 18, Pozzilli, 86077 Isernia, Italy
| | - Francesco Pierelli
- Headache Clinic, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Neuromed, Via Atinense 18, Pozzilli, 86077 Isernia, Italy
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Omland PM, Uglem M, Engstrøm M, Linde M, Hagen K, Sand T. Modulation of visual evoked potentials by high-frequency repetitive transcranial magnetic stimulation in migraineurs. Clin Neurophysiol 2014; 125:2090-9. [PMID: 24589349 DOI: 10.1016/j.clinph.2014.01.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/14/2013] [Accepted: 01/29/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE High-frequency repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability. We investigated its effect on visual evoked potentials (VEPs) in migraine. METHODS Thirty-two headache-free controls (CO), 25 interictal (MINT) and 7 preictal migraineurs (MPRE) remained after exclusions. VEPs to 8' and 65' checks were averaged in six blocks of 100 single responses. VEPs were recorded before, directly after and 25min after 10Hz rTMS. The study was blinded for diagnosis during recording and for diagnosis and block number during analysis. First block amplitudes and habituation (linear amplitude change over blocks) were analysed with repeated measures ANOVA. RESULTS With 65' checks, N70-P100 habituation was reduced in MINT compared to CO after rTMS (p=0.013). With 8' checks, habituation was reduced in MPRE compared to MINT and CO after rTMS (p<0.016). No effects of rTMS on first block amplitudes were found. CONCLUSION RTMS reduced habituation only in migraineurs, indicating increased responsivity to rTMS. The magnocellular visual subsystem may be affected interictally, while the parvocellular system may only be affected preictally. SIGNIFICANCE Migraineurs may have increased responsiveness to rTMS because of a cortical dysfunction that changes before a migraine attack.
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Affiliation(s)
- Petter M Omland
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.
| | - Martin Uglem
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway
| | - Morten Engstrøm
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway; St. Olavs Hospital, Department of Neurology and Clinical Neurophysiology, Trondheim, Norway
| | - Mattias Linde
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway; St. Olavs Hospital, Department of Neurology and Clinical Neurophysiology, Trondheim, Norway
| | - Knut Hagen
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway; St. Olavs Hospital, Department of Neurology and Clinical Neurophysiology, Trondheim, Norway
| | - Trond Sand
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway; St. Olavs Hospital, Department of Neurology and Clinical Neurophysiology, Trondheim, Norway
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Magis D, Vigano A, Sava S, d'Elia TS, Schoenen J, Coppola G. Pearls and pitfalls: electrophysiology for primary headaches. Cephalalgia 2014; 33:526-39. [PMID: 23671250 DOI: 10.1177/0333102413477739] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Primary headaches are functional neurological diseases characterized by a dynamic cyclic pattern over time (ictal/pre-/interictal). Electrophysiological recordings can non-invasively assess the activity of an underlying nervous structure or measure its response to various stimuli, and are therefore particularly appropriate for the study of primary headaches. Their interest, however, is chiefly pathophysiological, as interindividual, and to some extent intraindividual, variations preclude their use as diagnostic tools. AIM OF THE WORK This article will review the most important findings of electrophysiological studies in primary headache pathophysiology, especially migraine on which numerous studies have been published. RESULTS In migraine, the most reproducible hallmark is the interictal lack of neuronal habituation to the repetition of various types of sensory stimulations. The mechanism subtending this phenomenon remains uncertain, but it could be the consequence of a thalamocortical dysrythmia that results in a reduced cortical preactivation level. In tension-type headache as well as in cluster headache, there seems to be an impairment of central pain-controlling mechanisms but the studies are scarce and their outcomes are contradictory. The discrepancies between studies might be as a result of methodological differences as well as patients' dissimilarities, which are also discussed. CONCLUSIONS AND PERSPECTIVES Electrophysiology is complementary to functional neuroimaging and will undoubtedly remain an important tool in headache research. One of its upcoming applications is to help select neurostimulation techniques and protocols that correct best the functional abnormalities detectable in certain headache disorders.
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Affiliation(s)
- Delphine Magis
- Headache Research Unit, University Department of Neurology, CHR Citadelle, Liege 4000, Belgium.
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Tedeschi G, Russo A, Tessitore A. Relevance of functional neuroimaging studies for understanding migraine mechanisms. Expert Rev Neurother 2013; 13:275-85. [PMID: 23448217 DOI: 10.1586/ern.13.20] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Advances in imaging have provided further insights into the complex migraine pathophysiology. Functional neuroimaging by means of PET and functional MRI studies have addressed crucial migraine-related issues, improving our understanding of the circuitry that may be involved in the generation, maintenance and recurrence of pain symptoms in migraine. In the last few years, a growing body of imaging literature has also explored pathophysiology of associated migraine symptoms. Of great interest will be the use of advanced imaging techniques to elucidate neural correlates of migraine prodromal, in order to identify clinical subgroups of migrainous subjects. However, the interpretation of the biological significance of these various functional changes could remain incomplete without a combination of expanding genomic information about neurochemical pathways and genetic polymorphisms linked to specific migraine subtypes. Hopefully, a more detailed picture of the migraine neurobiology will emerge from future neuroimaging studies, which may eventually lead to better and more rational treatments.
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Affiliation(s)
- Gioacchino Tedeschi
- Headache Center, Department of Neurology, Second University of Naples, Naples, Italy.
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79
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Coppola G, Di Lorenzo C, Schoenen J, Pierelli F. Habituation and sensitization in primary headaches. J Headache Pain 2013; 14:65. [PMID: 23899115 PMCID: PMC3733593 DOI: 10.1186/1129-2377-14-65] [Citation(s) in RCA: 163] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 07/21/2013] [Indexed: 11/20/2022] Open
Abstract
The phenomena of habituation and sensitization are considered most useful for studying the neuronal substrates of information processing in the CNS. Both were studied in primary headaches, that are functional disorders of the brain characterized by an abnormal responsivity to any kind of incoming innocuous or painful stimuli and it's cycling pattern over time (interictal, pre-ictal, ictal). The present review summarizes available data on stimulus responsivity in primary headaches obtained with clinical neurophysiology. In migraine, the majority of electrophysiological studies between attacks have shown that, for a number of different sensory modalities, the brain is characterised by a lack of habituation of evoked responses to repeated stimuli. This abnormal processing of the incoming information reaches its maximum a few days before the beginning of an attack, and normalizes during the attack, at a time when sensitization may also manifest itself. An abnormal rhythmic activity between thalamus and cortex, namely thalamocortical dysrhythmia, may be the pathophysiological mechanism subtending abnormal information processing in migraine. In tension-type headache (TTH), only few signs of deficient habituation were observed only in subgroups of patients. By contrast, using grand-average responses indirect evidence for sensitization has been found in chronic TTH with increased nociceptive specific reflexes and evoked potentials. Generalized increased sensitivity to pain (lower thresholds and increased pain rating) and a dysfunction in supraspinal descending pain control systems may contribute to the development and/or maintenance of central sensitization in chronic TTH. Cluster headache patients are characterized during the bout and on the headache side by a pronounced lack of habituation of the brainstem blink reflex and a general sensitization of pain processing. A better insight into the nature of these ictal/interictal electrophysiological dysfunctions in primary headaches paves the way for novel therapeutic targets and may allow a better understanding of the mode of action of available therapies.
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Affiliation(s)
- Gianluca Coppola
- Department of Neurophysiology of Vision and Neurophthalmology, G.B. Bietti Foundation IRCCS, Via Livenza 3, 00198, Rome, Italy
| | | | - Jean Schoenen
- Headache Research Unit, University Department of Neurology & GIGA-Neurosciences, Liège University, Liège, Belgium
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Hadjikhani N, Ward N, Boshyan J, Napadow V, Maeda Y, Truini A, Caramia F, Tinelli E, Mainero C. The missing link: enhanced functional connectivity between amygdala and visceroceptive cortex in migraine. Cephalalgia 2013; 33:1264-8. [PMID: 23720503 DOI: 10.1177/0333102413490344] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Migraine is a neurovascular disorder in which altered functional connectivity between pain-modulating circuits and the limbic system may play a role. Cortical spreading depression (CSD), which underlies migraine aura (MWA), induces C-fos expression in the amygdala. The role of CSD and amygdala connectivity in migraine without aura (MwoA) is less clear and may differentiate migraine from other chronic pain disorders. METHODS Using resting-state functional MRI, we compared functional connectivity between the amygdala and the cortex in MWA and MWoA patients as well as in healthy subjects and in two other chronic pain conditions not associated with CSD: trigeminal neuralgia (TGN) and carpal tunnel syndrome (CTS). RESULTS Amygdala connectivity in both MWA and MWoA was increased to the visceroceptive insula relative to all other groups examined. CONCLUSION The observed increased connectivity within the limbic/viscerosensory network, present only in migraineurs, adds to the evidence of a neurolimbic pain network dysfunction and may reflect repetitive episodes of CSD leading to the development of migraine pain.
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Affiliation(s)
- Nouchine Hadjikhani
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, MA, USA
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Viganò A, D'Elia TS, Sava SL, Auvé M, De Pasqua V, Colosimo A, Di Piero V, Schoenen J, Magis D. Transcranial Direct Current Stimulation (tDCS) of the visual cortex: a proof-of-concept study based on interictal electrophysiological abnormalities in migraine. J Headache Pain 2013; 14:23. [PMID: 23566101 PMCID: PMC3620516 DOI: 10.1186/1129-2377-14-23] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 03/02/2013] [Indexed: 11/14/2022] Open
Abstract
Background Preventive pharmacotherapy for migraine is not satisfactory because of the low efficacy/tolerability ratio of many available drugs. Novel and more efficient preventive strategies are therefore warranted. Abnormal excitability of cortical areas appears to play a pivotal role in migraine pathophysiology. Transcranial direct current stimulation (tDCS) is a non-invasive and safe technique that is able to durably modulate the activity of the underlying cerebral cortex, and is being tested in various medical indications. The results of small open studies using tDCS in migraine prophylaxis are conflicting, possibly because the optimal stimulation settings and the brain targets were not well chosen. We have previously shown that the cerebral cortex, especially the visual cortex, is hyperresponsive in migraine patients between attacks and provided evidence from evoked potential studies that this is due to a decreased cortical preactivation level. If one accepts this concept, anodal tDCS over the visual cortex may have therapeutic potentials in migraine prevention, as it is able to increase neuronal firing. Objective To study the effects of anodal tDCS on visual cortex activity in healthy volunteers (HV) and episodic migraine without aura patients (MoA), and its potentials for migraine prevention. Methods We recorded pattern-reversal visual evoked potentials (VEP) before and after a 15-min session of anodal tDCS over the visual cortex in 11 HV and 13 MoA interictally. Then 10 MoA patients reporting at least 4 attacks/month subsequently participated in a therapeutic study, and received 2 similar sessions of tDCS per week for 8 weeks as migraine preventive therapy. Results In HV as well as in MoA, anodal tDCS transiently increased habituation of the VEP N1P1 component. VEP amplitudes were not modified by tDCS. Preventive treatment with anodal tDCS turned out to be beneficial in MoA: migraine attack frequency, migraine days, attack duration and acute medication intake significantly decreased during the treatment period compared to pre-treatment baseline (all p < 0.05), and this benefit persisted on average 4.8 weeks after the end of tDCS. Conclusions Anodal tDCS over the visual cortex is thus able to increase habituation to repetitive visual stimuli in healthy volunteers and in episodic migraineurs, who on average lack habituation interictally. Moreover, 2 weekly sessions of anodal tDCS had a significant preventive anti- migraine effect, proofing the concept that the low preactivation level of the visual cortex in migraine patients can be corrected by an activating neurostimulation. The therapeutic results indicate that a larger sham-controlled trial using the same tDCS protocol is worthwhile.
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Affiliation(s)
- Alessandro Viganò
- Headache Research Unit, Dept of Neurology, University of Liège, Liege, Belgium
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82
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Coppola G, Parisi V, Di Lorenzo C, Serrao M, Magis D, Schoenen J, Pierelli F. Lateral inhibition in visual cortex of migraine patients between attacks. J Headache Pain 2013; 14:20. [PMID: 23565983 PMCID: PMC3620512 DOI: 10.1186/1129-2377-14-20] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 02/25/2013] [Indexed: 11/18/2022] Open
Abstract
Background The interictal deficit of habituation to repetitive visual stimuli in migraine patients could be due to deficient intracortical inhibition and/or to low cortical pre-activation levels. Which of these abnormalities contributes more to the habituation deficit cannot be determined with the common methods used to record transient visual responses. We investigated lateral inhibition in the visual cortex during the migraine cycle and in healthy subjects by using differential temporal modulations of radial windmill-dartboard (WD) or partial-windmill (PW) visual patterns. Methods Transient (TR-VEP) and steady-state visual-evoked potentials (SS-VEP) were recorded in 65 migraine patients (21 without and 22 with aura between attacks; 22 patients during an attack) and in 21 healthy volunteers (HV). Three stimulations were used in each subject: classic checkerboard pattern (contrast-reversion 3.1Hz), WD and PW (contrast-reversion ~4Hz). For each randomly presented stimulation protocol, 600 sweeps were acquired and off-line partitioned in 6 blocks of 100. Fourier analysis allowed data to extract in SS-VEP the fundamental (1H) and the second harmonic (2H) components that reflect respectively short-(WD) and long- range lateral inhibition (attenuation of 2H in WD compared to PW). Results Compared to HV, migraineurs recorded interictally had significantly less habituation of the N1-P1 TR-VEP component over subsequent blocks and they tended to have a smaller 1st block amplitude. 1H amplitude in the 1st block of WD SS-VEP was significantly greater than in HV and habituated in successive blocks, contrasting with an amplitude increase in HV. Both the interictal TR-VEP and SS-VEP abnormalities normalized during an attack. There was no significant between group difference in the PW 2H amplitude and its attenuation. When data of HV and migraine patients were combined, the habituation slope of WD-VEP 1H was negatively correlated with that of TR-VEP N1-P1 and with number of days since the last migraine attack. Conclusion These results are in favour of a migraine cycle-dependent imbalance between excitation and inhibition in the visual cortex. We hypothesize that an interictal hypoactivity of monaminergic pathways may cause a functional disconnection of the thalamus in migraine leading to an abnormal intracortical short-range lateral inhibition that could contribute to the habituation deficit observed during stimulus repetition.
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Affiliation(s)
- Gianluca Coppola
- Departmen of Neurophysiology of Vision and Neuroophtalmology, G,B, Bietti Foundation IRCCS, Via Livenza 3-00198, Rome, Italy.
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de Tommaso M, Stramaglia S, Marinazzo D, Trotta G, Pellicoro M. Functional and effective connectivity in EEG alpha and beta bands during intermittent flash stimulation in migraine with and without aura. Cephalalgia 2013; 33:938-47. [DOI: 10.1177/0333102413477741] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives: This research was a case-control study to evaluate functional and effective connectivity patterns in ongoing electroencephalography (EEG) under repetitive photic stimulation in the interictal phase of migraine patients with and without aura compared to nonmigraine controls. Methods: EEG was recorded by six scalp electrodes from 19 migraine without aura patients (MO), 19 migraine with aura patients (MA) and 11 healthy subjects (control group (N)). Flash stimuli were presented at 9–27 Hz frequencies. Phase synchronization after Hilbert transform and Granger causality were evaluated filtering the EEG in alpha and beta bands. Results: Phase synchronization increased in alpha band in MO, and decreased in beta band in MA, with respect to controls. The intensity of directed interactions in beta band, revealed by Granger causality, increased in MA compared to both MO patients and controls. Discussion: There were clear differences in ongoing EEG under visual stimulation, which emerged between the two forms of migraine, probably subtended by increased cortical activation in migraine with aura, and compensatory phenomena of reduced connectivity and functional networks segregation, occurring in patients not experiencing aura symptoms. Further investigation may confirm whether the clinical manifestation of aura symptoms is subtended by a peculiar neuronal connectivity pattern.
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Affiliation(s)
- Marina de Tommaso
- Dipartimento di Neuroscienze e Organi di senso, Università degli Studi di Bari Aldo Moro, Italy
| | | | - Daniele Marinazzo
- Faculty of Psychology and Educational Sciences, Department of Data Analysis, Ghent University, Belgium
| | - Gabriele Trotta
- Dipartimento di Fisica, Università degli Studi di Bari Aldo Moro and INFN, Italy
| | - Mario Pellicoro
- Dipartimento di Fisica, Università degli Studi di Bari Aldo Moro and INFN, Italy
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84
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Datta R, Aguirre GK, Hu S, Detre JA, Cucchiara B. Interictal cortical hyperresponsiveness in migraine is directly related to the presence of aura. Cephalalgia 2013; 33:365-74. [PMID: 23359872 DOI: 10.1177/0333102412474503] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The objective of this study was to compare the interictal cortical response to a visual stimulus between migraine with aura (MWA), migraine without aura (MwoA), and control subjects. METHODS In a prospective case-control study, blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) was used to assess the response to a visual stimulus and arterial spin labeled perfusion MR to determine resting cerebral blood flow. A standardized questionnaire was used to assess interictal visual discomfort. RESULTS Seventy-five subjects (25 MWA, 25 MwoA, and 25 controls) were studied. BOLD fMRI response to visual stimulation within primary visual cortex was greater in MWA (3.09 ± 0.15%) compared to MwoA (2.36 ± 0.13%, P = 0.0008) and control subjects (2.47 ± 0.11%, P = 0.002); responses were also greater in the lateral geniculate nuclei in MWA. No difference was found between MwoA and control groups. Whole brain analysis showed that increased activation in MWA was confined to the occipital pole. Regional resting cerebral blood flow did not differ between groups. MWA and MwoA subjects had significantly greater levels of interictal visual discomfort compared to controls ( P = 0.008 and P = 0.005, respectively), but this did not correlate with BOLD response. CONCLUSIONS Despite similar interictal symptoms of visual discomfort, only MWA subjects have cortical hyperresponsiveness to visual stimulus, suggesting a direct connection between cortical hyperresponsiveness and aura itself.
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Omland PM, Nilsen KB, Uglem M, Gravdahl G, Linde M, Hagen K, Sand T. Visual Evoked Potentials in Interictal Migraine: No Confirmation of Abnormal Habituation. Headache 2013; 53:1071-86. [DOI: 10.1111/head.12006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2012] [Indexed: 12/13/2022]
Affiliation(s)
- Petter M. Omland
- Department of Neuroscience; Norwegian University of Science and Technology; Trondheim; Norway
| | - Kristian B. Nilsen
- Department of Neuroscience; Norwegian University of Science and Technology; Trondheim; Norway
| | - Martin Uglem
- Department of Neuroscience; Norwegian University of Science and Technology; Trondheim; Norway
| | - Gøril Gravdahl
- Department of Neuroscience; Norwegian University of Science and Technology; Trondheim; Norway
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Abstract
Many people who suffer from primary headache (ie, headache without an identifiable cause) are resistant or intolerant to available drugs. During the past decade, central and peripheral neurostimulation procedures have been investigated in such individuals--up to now, about 1200 worldwide. Techniques used range from invasive methods such as deep brain stimulation of the posterior hypothalamus, to minimally invasive percutaneous electrode implantation used in occipital nerve stimulation, or non-invasive methods such as transcranial magnetic stimulation. Although some of these procedures have been studied extensively, sham-controlled trials are sparse and the precise mode of action of such stimulation remains largely unknown. Nonetheless, occipital nerve stimulation and deep brain stimulation of the posterior hypothalamus seem to be effective in people with chronic cluster headache, and occipital nerve stimulation is promising in chronic migraine. Trial data for other techniques are scarce, but external and minimally invasive approaches should be privileged in future studies.
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Affiliation(s)
- Delphine Magis
- Headache Research Unit, Department of Neurology, University of Liège, Belgium
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88
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Thabet M, Wilkinson F, Wilson HR, Karanovic O. The locus of flicker adaptation in the migraine visual system: a dichoptic study. Cephalalgia 2012; 33:5-19. [PMID: 23147164 DOI: 10.1177/0333102412462640] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Flickering light has been shown to sensitize the migraine visual system at high stimulus contrast while elevating thresholds at low contrast. The present study employs a dichoptic psychophysical paradigm to ask whether the abnormal adaptation to flicker in migraine occurs before or after the binocular combination of inputs from the two eyes in the visual cortex. METHODS Following adaptation to high contrast flicker presented to one eye only, flicker contrast increment thresholds were measured in each eye separately using dichoptic viewing. RESULTS Modest interocular transfer of adaptation was seen in both migraine and control groups at low contrast. Sensitization at high contrast in migraine relative to control participants was seen in the adapted eye only, and an unanticipated threshold elevation occurred in the non-adapted eye. Migraineurs also showed significantly lower aversion thresholds to full field flicker than control participants, but aversion scores and increment thresholds were not correlated. CONCLUSIONS The results are simulated with a three-stage neural model of adaptation that points to strong adaptation at monocular sites prior to binocular combination, and weaker adaptation at the level of cortical binocular neurons. The sensitization at high contrast in migraine is proposed to result from stronger adaptation of inhibitory neurons, which act as a monocular normalization pool.
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Abstract
PURPOSE OF REVIEW Most pharmacological treatments of primary headache disorders are partially effective and have cumbersome side effects. Therapies with better efficacy and tolerance are needed. Neurostimulation techniques may have this potential. This is an attempt to summarize the latest clinical trial results published in the field. RECENT FINDINGS Hypothalamic deep brain stimulation is effective in drug-resistant chronic cluster headache (drCCH) but not riskless. Recent anatomical MRI studies indicate that the effective stimulation sites are rather widespread. Occipital nerve stimulation (ONS) seems to be effective in up to 76% of drCCH patients and its benefit long-lasting. A minority of patients are able to abandon preventive drugs. Its mechanism of action appears nonspecific. In chronic migraine, randomized controlled trials of ONS showed recently encouraging results, but long-term studies are missing. An ongoing sham-controlled trial suggests sphenopalatine ganglion neurostimulation (SPGS) efficacy in drCCH acute treatment, but possibly also in preventive therapy. Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) modulate cortical excitability and connectivity. TMS could prevent headache when applied over the occipital cortex during the migraine aura. Repetitive TMS and tDCS have provided mixed results in a few small studies and warrant further trials. SUMMARY Neurostimulation therapies inaugurate a new era in headache management and offer a promising alternative to medications. Future studies are necessary to provide evidence-based efficacy data, knowledge on their mode of action and information about their pharmaco-economic advantages.
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Magis D, Boon E, Coppola G, Daron A, Schoenen J. A novel CACNA1A mutation results in episodic ataxia with migrainous features without headache. Cephalalgia 2012; 32:1147-9. [PMID: 22942164 DOI: 10.1177/0333102412459572] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The mechanisms subtending migrainous features, like sensoriphobia, remain poorly understood even though recent works have shed new light on their mechanisms. CASE REPORT A 24-year-old woman consulted the headache clinic because of frequent paroxysmal attacks of strong sensoriphobia, digestive signs, moderate ataxia and a need to lie in the dark, without any headache. The symptoms had begun in infancy and the patient had been treated for hysteria, then for epilepsy. As she had some typical features of episodic ataxia type 2, an analysis of CACNA1A gene was performed and demonstrated a novel c3995 + 1G>A mutation. The same mutation was also discovered in her young son, who had an ataxia of unknown origin. Both remarkably improved under acetazolamide. CONCLUSIONS This observation suggests that paroxysmal sensoriphobia and digestive signs can occur together in bouts in neurological conditions other than migraine, and in the absence of head pain. It raises interesting hypotheses about the central pathways driving these symptoms.
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Affiliation(s)
- Delphine Magis
- Headache Clinic and Research Unit, University Department of Neurology, CHR Citadelle, Belgium.
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Restuccia D, Vollono C, Del Piero I, Martucci L, Zanini S. Somatosensory High Frequency Oscillations reflect clinical fluctuations in migraine. Clin Neurophysiol 2012; 123:2050-6. [PMID: 22554785 DOI: 10.1016/j.clinph.2012.03.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 03/15/2012] [Accepted: 03/16/2012] [Indexed: 12/13/2022]
Abstract
OBJECTIVE It has been demonstrated that the early part of 600 Hz High Frequency Oscillations (HFOs), probably generated in the terminal part of thalamo-cortical somatosensory radiations, are abnormally reduced between attacks in migraineurs. We aimed at verifying whether spontaneous clinical fluctuations in migraine are correlated to HFO changes. METHODS We recorded somatosensory evoked potentials in 28 migraine patients. Clinical fluctuations (number of attacks in the 6 months preceding and following the test) were correlated to the HFOs' amplitudes. Moreover, eight out of 28 patients underwent a longer follow-up, including HFO control and clinical observation during the 12 months following the baseline recording. RESULTS The amplitude of early presynaptic HFOs was significantly correlated to the clinical evolution, since spontaneous worsening was associated with reduced presynaptic HFOs, whereas spontaneous improvement was associated with enhanced presynaptic HFOs (correlation test, p<0.05). No correlation was found between the amplitude of postsynaptic HFOs and clinical fluctuations. Patients undergoing longer follow-up showed substantially unchanged HFOs, accordingly with their stable clinical condition. CONCLUSIONS HFOs' enhancement in spontaneously improved patients can reflect the increased activity of brainstem arousal related structures, which in turn increases the thalamo-cortical drive and the cortical lateral inhibition mediated by GABAergic interneurons. SIGNIFICANCE HFOs' recording could represent a useful tool in the functional assessment of migraine.
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92
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Omland PM, Nilsen KB, Sand T. Habituation measured by pattern reversal visual evoked potentials depends more on check size than reversal rate. Clin Neurophysiol 2011; 122:1846-53. [PMID: 21414838 DOI: 10.1016/j.clinph.2011.02.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 01/14/2011] [Accepted: 02/13/2011] [Indexed: 10/18/2022]
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Descamps B, Vandemaele P, Reyngoudt H, Deblaere K, Leybaert L, Paemeleire K, Achten E. Absence of haemodynamic refractory effects in patients with migraine without aura – an interictal fMRI study. Cephalalgia 2011; 31:1220-31. [DOI: 10.1177/0333102411415881] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background: In healthy controls, haemodynamic refractory effects are observed with blood-oxygenation-level dependent (BOLD) functional MRI (fMRI): the haemodynamic response function (HRF) to the second stimulus in a pair of stimuli with short interstimulus interval (ISI) shows a decreased amplitude and an increased time-to-peak. We hypothesize that there may be interictal haemodynamic abnormalities in migraineurs. Methods: An event-related fMRI design with paired face stimuli and varying ISIs was used to measure interictal HRFs in the face recognition area of patients with migraine without aura (MwoA) and controls. Net responses to the second stimulus in a pair were calculated and averaged per participant. Several characterizing parameters of the net responses were quantified and examined within each group. Results: Refractory effects were not observed in our patient group. There are no changes in the net responses compared with the reference situation in patients, irrespective of the ISI, whereas in controls all HRF parameters are decreased or delayed for an ISI of 1 second. Conclusion: This is the first fMRI study investigating the haemodynamic refractory effects in MwoA patients. Unlike in controls, these effects are not observed in migraineurs. Although currently unclear, it is tempting to speculate that this observation reflects the neurovascular correlate of lack of habituation measured with evoked potentials in migraineurs.
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Coppola G, Crémers J, Gérard P, Pierelli F, Schoenen J. Effects of light deprivation on visual evoked potentials in migraine without aura. BMC Neurol 2011; 11:91. [PMID: 21794160 PMCID: PMC3158744 DOI: 10.1186/1471-2377-11-91] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 07/27/2011] [Indexed: 11/21/2022] Open
Abstract
Background The mechanisms underlying the interictal habituation deficit of cortical visual evoked potentials (VEP) in migraine are not well understood. Abnormal long-term functional plasticity of the visual cortex may play a role and it can be assessed experimentally by light deprivation (LD). Methods We have compared the effects of LD on VEP in migraine patients without aura between attacks (MO, n = 17) and in healthy volunteers (HV, n = 17). Six sequential blocks of 100 averaged VEP at 3.1 Hz were recorded before and after 1 hour of LD. We measured VEP P100 amplitude of the 1st block of 100 sweeps and its change over 5 sequential blocks of 100 responses. Results In HV, the consequence of LD was a reduction of 1st block VEP amplitude and of the normal habituation pattern. By contrast, in MO patients, the interictal habituation deficit was not significantly modified, although 1st block VEP amplitude, already lower than in HV before LD, further decreased after LD. Conclusions Light deprivation is thought to decrease both excitatory and subsequent inhibitory processes in visual cortex, which is in line with our findings in healthy volunteers. The VEP results in migraine patients suggest that early excitation was adequately suppressed, but not the inhibitory mechanisms occurring during long term stimulation and habituation. Accordingly, deficient intracortical inhibition is unlikely to be a primary factor in migraine pathophysiology and the habituation deficit.
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Affiliation(s)
- Gianluca Coppola
- G.B. Bietti Eye Foundation-IRCCS, Dept of Neurophysiology of Vision and Neuroophtalmology, Rome, Italy.
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Shibata K, Yamane K, Nishimura Y, Kondo H, Otuka K. Spatial frequency differentially affects habituation in migraineurs: a steady-state visual-evoked potential study. Doc Ophthalmol 2011; 123:65-73. [PMID: 21769699 DOI: 10.1007/s10633-011-9281-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 07/04/2011] [Indexed: 11/29/2022]
Abstract
A lack of habituation in visual-evoked potentials (VEPs) is the main abnormality observed in migraineurs. However, no study of steady-state VEPs has yet evaluated pattern-reversal stimuli with respect to habituation behavior or spatial frequency. The aim of this study was to clarify habituation behavior in migraineurs between attacks and to establish characteristics of VEPs in these patients. Steady-state VEPs were sequentially recorded as checkerboard patterns in four consecutive blocks from 12 patients with migraine without aura (MO), 12 patients with migraine with aura (MA), and 12 healthy controls (HC) at four spatial frequencies of 0.5, 1.0, 2.0, and 4.0 cycles per degree (cpd) with a stimulus rate of 7.5 Hz (15 reversal/s). VEP amplitudes were consistently higher in migraineurs. However, habituation was not demonstrated in HCs, and migraineurs did not reveal a clear lack of habituation. MAs exhibited high-amplitude VEPs, depending on spatial frequency. In the MA patients, amplitude differences reached statistical significance at 2.0 cpd. The sequential amplitude changes at 0.5 cpd were significantly different in MAs compared with HCs. Migraine patients exhibited high-amplitude VEPs, which were dependent on spatial frequency, and may be related to altered excitability in pre-cortical and cortical visual processing.
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Affiliation(s)
- Koichi Shibata
- Department of Medicine, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567, Japan.
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Bjørk M, Stovner LJ, Hagen K, Sand T. What initiates a migraine attack? Conclusions from four longitudinal studies of quantitative EEG and steady-state visual-evoked potentials in migraineurs. Acta Neurol Scand 2011:56-63. [PMID: 21711258 DOI: 10.1111/j.1600-0404.2011.01545.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Quantitative electroencephalograpic (QEEG) frequency spectra and steady-state visual-evoked potentials (SSVEP) are indicators of corticothalamic excitability (e.g., arousal). Increased interictal excitability is suggested to be an important element in the migraine pathophysiology. In this paper, we summarize our results from four studies of QEEG and SSVEP recordings in migraineurs interictally and in the days before an attack with the intention to shed light on attack-initiating mechanisms. MATERIAL AND METHODS Thirty-two healthy controls, 33 migraineurs without and eight with aura each had three EEGs with photic stimulation on different days. Using the patient headache diaries, we classified the recordings as interictal, preictal, ictal, or post-ictal retrospectively. Interictal recordings were compared pairwise with attack-related EEGs from the same patient as well as with control EEGs. We also correlated clinical variables with the QEEG and SSVEP data. RESULTS Between attacks, we found increased relative theta activity and attenuated medium-frequency photic responses in migraineurs without aura compared with those in controls. Within 36 h before the attack, slow and asymmetric EEG activity developed. Increased trigger sensitivity and photophobia correlated with higher theta power and depressed photic responses. Attack duration, migraine history duration, and pain intensity were associated with EEG slowing. CONCLUSIONS A general tendency toward EEG slowing and depression of photic responses characterized the migraine group. This pattern was also related to increased severity of symptoms. A change in cortical activity occurred within 36 h before attacks. Our results indicate that thalamocortical hypoexcitability is associated with attack initiation and sensory hypersensitivity in migraine.
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Affiliation(s)
- M Bjørk
- Department of Neuroscience, Norwegian University of Science and Technology, Olav Kyrresgate 9, Trondheim, Norway.
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Ambrosini A, Coppola G, Gérardy PY, Pierelli F, Schoenen J. Intensity dependence of auditory evoked potentials during light interference in migraine. Neurosci Lett 2011; 492:80-3. [DOI: 10.1016/j.neulet.2011.01.060] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 01/21/2011] [Accepted: 01/22/2011] [Indexed: 11/30/2022]
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Moulton EA, Becerra L, Maleki N, Pendse G, Tully S, Hargreaves R, Burstein R, Borsook D. Painful heat reveals hyperexcitability of the temporal pole in interictal and ictal migraine States. Cereb Cortex 2011; 21:435-48. [PMID: 20562317 PMCID: PMC3020583 DOI: 10.1093/cercor/bhq109] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
During migraine attacks, alterations in sensation accompanying headache may manifest as allodynia and enhanced sensitivity to light, sound, and odors. Our objective was to identify physiological changes in cortical regions in migraine patients using painful heat and functional magnetic resonance imaging (fMRI) and the structural basis for such changes using diffusion tensor imaging (DTI). In 11 interictal patients, painful heat threshold + 1°C was applied unilaterally to the forehead during fMRI scanning. Significantly greater activation was identified in the medial temporal lobe in patients relative to healthy subjects, specifically in the anterior temporal pole (TP). In patients, TP showed significantly increased functional connectivity in several brain regions relative to controls, suggesting that TP hyperexcitability may contribute to functional abnormalities in migraine. In 9 healthy subjects, DTI identified white matter connectivity between TP and pulvinar nucleus, which has been related to migraine. In 8 patients, fMRI activation in TP with painful heat was exacerbated during migraine, suggesting that repeated migraines may sensitize TP. This article investigates a nonclassical role of TP in migraineurs. Observed temporal lobe abnormalities may provide a basis for many of the perceptual changes in migraineurs and may serve as a potential interictal biomarker for drug efficacy.
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Affiliation(s)
- E A Moulton
- Pain/Analgesia Imaging Neuroscience Group, Department of Psychiatry, Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478, USA
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Changes in visual-evoked potential habituation induced by hyperventilation in migraine. J Headache Pain 2010; 11:497-503. [PMID: 20625915 PMCID: PMC3476226 DOI: 10.1007/s10194-010-0239-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 06/24/2010] [Indexed: 11/24/2022] Open
Abstract
Hyperventilation is often associated with stress, an established trigger factor for migraine. Between attacks, migraine is associated with a deficit in habituation to visual-evoked potentials (VEP) that worsens just before the attack. Hyperventilation slows electroencephalographic (EEG) activity and decreases the functional response in the occipital cortex during visual stimulation. The neural mechanisms underlying deficient-evoked potential habituation in migraineurs remain unclear. To find out whether hyperventilation alters VEP habituation, we recorded VEPs before and after experimentally induced hyperventilation lasting 3 min in 18 healthy subjects and 18 migraine patients between attacks. We measured VEP P100 amplitudes in six sequential blocks of 100 sweeps and habituation as the change in amplitude over the six blocks. In healthy subjects, hyperventilation decreased VEP amplitude in block 1 and abolished the normal VEP habituation. In migraine patients, hyperventilation further decreased the already low block 1 amplitude and worsened the interictal habituation deficit. Hyperventilation worsens the habituation deficit in migraineurs possibly by increasing dysrhythmia in the brainstem-thalamo-cortical network.
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Walton KD, Dubois M, Llinás RR. Abnormal thalamocortical activity in patients with Complex Regional Pain Syndrome (CRPS) Type I. Pain 2010; 150:41-51. [DOI: 10.1016/j.pain.2010.02.023] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 01/19/2010] [Accepted: 02/12/2010] [Indexed: 11/26/2022]
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