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Cutrona C, Marchet F, Costanzo M, De Bartolo MI, Leodori G, Ferrazzano G, Conte A, Fabbrini G, Berardelli A, Belvisi D. Exploring the Central Mechanisms of Botulinum Toxin in Parkinson's Disease: A Systematic Review from Animal Models to Human Evidence. Toxins (Basel) 2023; 16:9. [PMID: 38251226 PMCID: PMC10818853 DOI: 10.3390/toxins16010009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/14/2023] [Accepted: 12/19/2023] [Indexed: 01/23/2024] Open
Abstract
Botulinum toxin (BoNT) is an effective and safe therapy for the symptomatic treatment of several neurological disturbances. An important line of research has provided numerous pieces of evidence about the mechanisms of action of BoNT in the central nervous system, especially in the context of dystonia and spasticity. However, only a few studies focused on the possible central effects of BoNT in Parkinson's disease (PD). We performed a systematic review to describe and discuss the evidence from studies focused on possible central effects of BoNT in PD animal models and PD patients. To this aim, a literature search in PubMed and SCOPUS was performed in May 2023. The records were screened according to title and abstract by two independent reviewers and relevant articles were selected for full-text review. Most of the papers highlighted by our review report that the intrastriatal administration of BoNT, through local anticholinergic action and the remodulation of striatal compensatory mechanisms secondary to dopaminergic denervation, induces an improvement in motor and non-motor symptoms in the absence of neuronal loss in animal models of PD. In human subjects, the data are scarce: a single neurophysiological study in tremulous PD patients found that the change in tremor severity after peripheral BoNT administration was associated with improved sensory-motor integration and intracortical inhibition measures. Further clinical, neurophysiological, and neuroimaging studies are necessary to clarify the possible central effects of BoNT in PD.
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Affiliation(s)
- Carolina Cutrona
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
| | - Francesco Marchet
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
| | - Matteo Costanzo
- Department of Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy;
| | - Maria Ilenia De Bartolo
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Giorgio Leodori
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Gina Ferrazzano
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
| | - Antonella Conte
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Giovanni Fabbrini
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Daniele Belvisi
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell’Università 30, 00185 Rome, Italy; (C.C.); (F.M.); (M.I.D.B.); (G.L.); (G.F.); (A.C.); (G.F.); (A.B.)
- IRCSS Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
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Belvisi D, Leodori G, Costanzo M, Conte A, Berardelli A. How does botulinum toxin really work? INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 169:441-479. [PMID: 37482400 DOI: 10.1016/bs.irn.2023.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Over the past 30 years, Botulinum toxin (BoNT) has emerged as an effective and safe therapeutic tool for a number of neurological conditions, including dystonia. To date, the exact mechanism of action of BoNT in dystonia is not fully understood. Although it is well known that BoNT mainly acts on the neuromuscular junction, a growing body of evidence suggests that the therapeutic effect of BoNT in dystonia may also depend on its ability to modulate peripheral sensory feedback from muscle spindles. Animal models also suggest a retrograde and anterograde BoNT transportation from the site of injection to central nervous system structures. In humans, however, BoNT central effects seem to depend on the modulation of afferent input rather than on BoNT transportation. In this chapter, we aimed to report and discuss research evidence providing information on the possible mechanisms of action of BoNT in relation to treatment of dystonia.
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Affiliation(s)
- Daniele Belvisi
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | - Giorgio Leodori
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | | | - Antonella Conte
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy.
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Riboldi GM, Frucht SJ. Is essential tremor a family of diseases or a syndrome? A family of diseases. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2022; 163:7-29. [PMID: 35750371 DOI: 10.1016/bs.irn.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
It is now well-established that essential tremor (ET) can manifest with different clinical presentations and progressions (i.e., upper limb tremor, head tremor, voice tremor, lower limb tremor, task- or position-specific tremor, or a combination of those). Common traits and overlaps are identifiable across these different subtypes of ET, including a slow rate of progression, a response to alcohol and a positive family history. At the same time, each of these manifestations are associated with specific demographic, clinical and treatment-response characteristics suggesting a family of diseases rather than a spectrum of a syndrome. Here we summarize the most important clinical, demographic, neuropathological and imagingfeatures of ET and of its subtypes to support ET as a family of identifiable conditions. This classification has relevance for counseling of patients with regard to disease progression and treatment response, as well as for the design of therapeutic clinical trials.
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Affiliation(s)
- Giulietta M Riboldi
- The Marlene and Paolo Fresco Institute for Parkinson's and Movement Disorders, New York University Langone Health, New York, NY, United States
| | - Steven J Frucht
- The Marlene and Paolo Fresco Institute for Parkinson's and Movement Disorders, New York University Langone Health, New York, NY, United States.
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Rare tremors and tremors occurring in other neurological disorders. J Neurol Sci 2022; 435:120200. [DOI: 10.1016/j.jns.2022.120200] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 02/07/2022] [Accepted: 02/17/2022] [Indexed: 12/21/2022]
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Datta A, Batra N, Pandey S. Primary Writing Tremor: Current Concepts. Ann Indian Acad Neurol 2021; 24:319-326. [PMID: 34446992 PMCID: PMC8370167 DOI: 10.4103/aian.aian_1264_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 12/19/2020] [Accepted: 12/30/2020] [Indexed: 11/07/2022] Open
Abstract
Primary Writing Tremor (PWT) is a type of task specific tremor which happens only while writing (Type A PWT) or assuming a writing position of the hand (Type B PWT). There is a considerable overlap of clinical features between PWT and writer's cramp which creates difficulty in diagnosing this condition in the clinic. PWT usually affects the dominant hand and is typically 5-7hz in frequency, worsened by anxiety, temporarily relieved by alcohol and associated with reduced writing speeds. There are a variety of hypotheses about the phenomenology of PWT (regarding whether it is a variant of essential tremor, focal dystonia or an independent entity). Unlike writer's cramp, PWT shows normal reciprocal inhibition of H reflex, does not exhibit excessive EMG activity in proximal muscles, and on fMRI shows underactivation of cingulum and overactivation of primary motor and supplementary areas. There are no randomised controlled trials currently for the treatment of PWT. Treatment modalities available are: medical treatment, botulinum toxin, surgical management (including DBS) as well as adaptive strategies and occupational therapy.
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Affiliation(s)
- Abhigyan Datta
- Maulana Azad Medical College, and Govind Ballabh Pant Postgraduate Institute of Medical Education and Research, New Delhi, India
| | - Nitya Batra
- Maulana Azad Medical College, and Govind Ballabh Pant Postgraduate Institute of Medical Education and Research, New Delhi, India
| | - Sanjay Pandey
- Maulana Azad Medical College, and Govind Ballabh Pant Postgraduate Institute of Medical Education and Research, New Delhi, India
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Hok P, Veverka T, Hluštík P, Nevrlý M, Kaňovský P. The Central Effects of Botulinum Toxin in Dystonia and Spasticity. Toxins (Basel) 2021; 13:155. [PMID: 33671128 PMCID: PMC7922085 DOI: 10.3390/toxins13020155] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/02/2021] [Accepted: 02/11/2021] [Indexed: 12/05/2022] Open
Abstract
In dystonic and spastic movement disorders, however different in their pathophysiological mechanisms, a similar impairment of sensorimotor control with special emphasis on afferentation is assumed. Peripheral intervention on afferent inputs evokes plastic changes within the central sensorimotor system. Intramuscular application of botulinum toxin type A (BoNT-A) is a standard evidence-based treatment for both conditions. Apart from its peripheral action on muscle spindles, a growing body of evidence suggests that BoNT-A effects could also be mediated by changes at the central level including cerebral cortex. We review recent studies employing electrophysiology and neuroimaging to investigate how intramuscular application of BoNT-A influences cortical reorganization. Based on such data, BoNT-A becomes gradually accepted as a promising tool to correct the maladaptive plastic changes within the sensorimotor cortex. In summary, electrophysiology and especially neuroimaging studies with BoNT-A further our understanding of pathophysiology underlying dystonic and spastic movement disorders and may consequently help develop novel treatment strategies based on neural plasticity.
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Affiliation(s)
| | - Tomáš Veverka
- Department of Neurology, Faculty of Medicine and Dentistry, University Hospital Olomouc, Palacký University Olomouc, 779 00 Olomouc, Czech Republic; (P.H.); (P.H.); (M.N.); (P.K.)
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Central Effects of Botulinum Neurotoxin-Evidence from Human Studies. Toxins (Basel) 2019; 11:toxins11010021. [PMID: 30621330 PMCID: PMC6356587 DOI: 10.3390/toxins11010021] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 12/25/2018] [Accepted: 12/31/2018] [Indexed: 11/24/2022] Open
Abstract
For more than three decades, Botulinum neurotoxin (BoNT) has been used to treat a variety of clinical conditions such as spastic or dystonic disorders by inducing a temporary paralysis of the injected muscle as the desired clinical effect. BoNT is known to primarily act at the neuromuscular junction resulting in a biochemical denervation of the treated muscle. However, recent evidence suggests that BoNT’s pharmacological properties may not only be limited to local muscular denervation at the injection site but may also include additional central effects. In this review, we report and discuss the current evidence for BoNT’s central effects based on clinical observations, neurophysiological investigations and neuroimaging studies in humans. Collectively, these data strongly point to indirect mechanisms via changes to sensory afferents that may be primarily responsible for the marked plastic effects of BoNT on the central nervous system. Importantly, BoNT-related central effects and consecutive modulation and/or reorganization of the brain may not solely be considered “side-effects” but rather an additional therapeutic impact responsible for a number of clinical observations that cannot be explained by merely peripheral actions.
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Vives-Rodriguez A, Kim CY, Louis ED. Primary Writing Tremor. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2018; 8:586. [PMID: 30402337 PMCID: PMC6214817 DOI: 10.7916/d8t740zz] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 07/30/2018] [Indexed: 12/01/2022]
Abstract
Background Primary writing tremor (PWT) is a rare condition; tremor occurs primarily while writing rather than during other tasks. Phenomenology Shown We illustrate the phenomenology of PWT and point out associated subtle dystonic posturing on neurological examination. Educational Value PWT is a tremor disorder that shares clinical features with both dystonia and essential tremor.
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Affiliation(s)
- Ana Vives-Rodriguez
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Christine Y Kim
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Elan D Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA.,Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA.,Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA
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Jhunjhunwala K, George L, Kotikalapudi R, Gupta PK, Lenka A, Stezin A, Naduthota RM, Yadav R, Gupta AK, Saini J, Pal PK. A preliminary study of the neuroanatomical correlates of primary writing tremor: role of cerebellum. Neuroradiology 2016; 58:827-36. [PMID: 27216204 DOI: 10.1007/s00234-016-1700-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/11/2016] [Indexed: 12/16/2022]
Abstract
INTRODUCTION To explore the neuroanatomical correlates of primary writing tremor (PWT) and the role of cerebellum, using advanced structural neuroimaging. Till date, there are no studies exploring the gray and white matter changes using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) in PWT. METHODS Ten male patients with PWT were evaluated clinically and with magnetic resonance imaging. VBM and DTI images of patients were compared with that of 10 healthy male subjects. Spatially unbiased infra-tentorial template (SUIT) analysis was done to investigate the alterations of cerebellar gray matter. Region-of-interest analysis was performed on regions observed to be significantly different on DTI analysis. RESULTS The mean duration of illness and mean age of the patients were 3.5 ± 1.9 and 51.7 ± 8.6 years, respectively. On VBM analysis, the cluster of gray matter atrophy was found in bilateral cerebellar areas of culmen and left declive, right superior and medial frontal gyrus, bilateral middle frontal gyrus, bilateral anterior cingulate gyrus, and bilateral parahippocampal gyrus. DTI showed significantly reduced fractional anisotrophy of the anterior thalamic radiation, cingulum, and inferior fronto-occipital fasciculus in PWT patients compared to controls. The axial diffusivity, mean diffusivity, and radial diffusivity maps did not reveal any significant differences. On SUIT analysis, significant atrophy was found in right uvula and semilunar lobule in patients with PWT compared to controls. CONCLUSIONS Our study found that patients with PWT had predominant gray matter atrophy in parts of cerebellum and frontal lobe along with white matter changes of the cingulum and frontal lobe connections.
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Affiliation(s)
- Ketan Jhunjhunwala
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India.,Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Lija George
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India
| | - Raviteja Kotikalapudi
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India
| | - Pradeep Kumar Gupta
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India
| | - Abhishek Lenka
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India.,Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Albert Stezin
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India.,Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Rajini M Naduthota
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India
| | - Ravi Yadav
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India
| | - Arun Kumar Gupta
- Departments of Neuroimaging and Interventional Radiology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Jitender Saini
- Departments of Neuroimaging and Interventional Radiology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health & Neurosciences, Hosur Road, Bangalore, 560029, Karnataka, India.
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Ward S, Bryant AL, Pietrosimone B, Bennell KL, Clark R, Pearce AJ. Cortical motor representation of the rectus femoris does not differ between the left and right hemisphere. J Electromyogr Kinesiol 2016; 28:46-52. [PMID: 26999234 DOI: 10.1016/j.jelekin.2016.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 02/16/2016] [Accepted: 03/07/2016] [Indexed: 11/25/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) involves non-invasive magnetic stimulation of the brain, and can be used to explore the corticomotor excitability and motor representations of skeletal muscles. However there is a lack of motor mapping studies in the lower limb and few conducted in healthy cohorts. The cortical motor representations of muscles can vary between individuals in terms of center position and area despite having a general localized region within the motor cortex. It is important to characterize the normal range for these variables in healthy cohorts to be able to evaluate changes in clinical populations. TMS was used in this cross-sectional study to assess the active motor threshold (AMT) and cortical representation area for rectus femoris in 15 healthy individuals (11M/4F 27.3±5.9years). No differences were found between hemispheres (Left vs. Right P=0.130) for AMT. In terms of y-axis center position no differences were found between hemispheres (Left vs. Right P=0.539), or for the x-axis center position (Left vs. Right P=0.076). Similarly, no differences in calculated area of the motor representation were found (Left vs. Right P=0.699) indicating symmetry between hemispheres.
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Affiliation(s)
- Sarah Ward
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia.
| | - Adam L Bryant
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
| | - Brian Pietrosimone
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, NC, United States
| | - Kim L Bennell
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
| | - Ross Clark
- School of Exercise Science, Australian Catholic University, VIC, Australia
| | - Alan J Pearce
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
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Schreglmann SR, Baumann CR, Waldvogel D. Mirror Writing Tremor: Dystonic Clues…. Mov Disord Clin Pract 2015; 2:316-317. [PMID: 30363557 DOI: 10.1002/mdc3.12182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 03/05/2015] [Accepted: 03/11/2015] [Indexed: 11/06/2022] Open
Affiliation(s)
- Sebastian R Schreglmann
- Department of Neurology University Hospital Zurich Zurich Switzerland.,Department of Neurology Kantonsspital St. Gallen St. Gallen Switzerland
| | | | - Daniel Waldvogel
- Department of Neurology University Hospital Zurich Zurich Switzerland
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Lee A, Furuya S, Altenmüller E. Epidemiology and treatment of 23 musicians with task specific tremor. JOURNAL OF CLINICAL MOVEMENT DISORDERS 2014; 1:5. [PMID: 26788331 PMCID: PMC4677731 DOI: 10.1186/2054-7072-1-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/03/2014] [Indexed: 11/22/2022]
Abstract
BACKGROUND Task specific tremors in musicians have been mainly described as primary bowing tremor in string instrumentalists in relatively small sample sizes. Our aim was to describe epidemiology, risk factors, phenomenology and treatment options of this disorder in 23 musicians of different instruments. METHODS We included 23 professional musicians (4 female, 19 male; mean age 51.5 ± 11.4 years) with a TSTM. During anamnesis, clinical examination, by mail or via telephone patients were asked for epidemiological, phenomenological information, risk factors and treatments. We then compared our findings to primary writing tremor, the most common task specific tremor. RESULTS Age at onset of the TST was 44.6 ± 13.6 years and tremor appeared 35.1 ± 13.5 years after beginning to play the instrument. The majority of patients were string instrumentalists, followed by woodwind instrumentalists. Other instrumentalists were a guitarist, pianist and percussionist respectively. In contrast to primary writing tremor, we also found proximal muscles of the upper extremity involved in tremor. A positive family history was found in Prior trauma was more common than in primary writing tremor. Treatment with a positive effect on tremor were in order of efficacy: Botulinumtoxin, Primidone, Propranolol, Trihexyphenidyl. No patient had undergone deep brain stimulation. CONCLUSION Task specific tremor in musicians is a heterogeneous disorder with a male gender predominance that shares many commonalities with PWT. The onset age as well as the time between starting to play the instrument and tremor onset has a wide range. Because previous trauma and overuse appear to be risk factors, preventive measures against playing related injuries are necessary. There appears to be a genetic predisposition for TST. No single beneficial medication exists and treatment of patients remains highly individual. It should be discussed, whether deep brain stimulation should be offered not only to patients that do not respond to any other medication but early in the course of the disease.
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Affiliation(s)
- André Lee
- Inistitute of Music Physiology and Musicians’ Medicine, Hannover University of Music, Drama and Media, Hannover, Germany
| | - Shinichi Furuya
- Inistitute of Music Physiology and Musicians’ Medicine, Hannover University of Music, Drama and Media, Hannover, Germany
| | - Eckart Altenmüller
- Inistitute of Music Physiology and Musicians’ Medicine, Hannover University of Music, Drama and Media, Hannover, Germany
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Lee A, Schoonderwaldt E, Chadde M, Altenmüller E. Movement induced tremor in musicians and non-musicians reflects adaptive brain plasticity. Front Psychol 2014; 5:824. [PMID: 25120522 PMCID: PMC4114260 DOI: 10.3389/fpsyg.2014.00824] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 07/10/2014] [Indexed: 11/16/2022] Open
Abstract
Evidence exists that motor dexterity is associated with a higher tremor amplitude of physiological tremor. Likewise, lower frequencies are associated with motor control. So far only case reports of a higher amplitude of physiological tremor in musicians exist. Moreover, no study has investigated lower frequencies during a finger movement task in musicians who can be regarded as a model of motor expertise. We developed a model and derived three hypotheses which we investigated in this study: (1) Tremor amplitude is higher in the range of physiological tremor and (2) higher for frequency ranges of dystonic tremor in musicians compared to non-musicians; (3) there is no difference in tremor amplitude at frequencies below 4 Hz. We measured tremor during a finger flexion-extension movement in 19 musicians (age 26.5 ± 8.2 years) and 24 age matched non-musicians (age 26.5 ± 8.7). By using empirical mode decomposition in combination with a Hilbert transform we obtained the instantaneous frequency and amplitude, allowing to compare tremor amplitudes throughout the movement at various frequency ranges. We found a significantly higher tremor amplitude in musicians for physiological tremor and a tendency toward a higher amplitude during most of the movement in the frequency range of 4-8 Hz, which, however, was not significant. No difference was found in the frequency range below 4 Hz for the flexion and for almost the entire extension movement. Our results corroborate findings that the 8-12 Hz oscillatory activity plays a role in motor dexterity. However, our results do not allow for the conclusion that tremor at the frequency range of 4-8 Hz is related to either plasticity induced changes that are beneficial for motor skill development nor to maladaptive changes as, e.g., focal dystonia.
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Affiliation(s)
- André Lee
- Institute for Music Physiology and Musicians’ Medicine, University of Music, Drama and Media HannoverHannover, Germany
| | - Erwin Schoonderwaldt
- Institute for Music Physiology and Musicians’ Medicine, University of Music, Drama and Media HannoverHannover, Germany
| | - Mareike Chadde
- Institute for Music Physiology and Musicians’ Medicine, University of Music, Drama and Media HannoverHannover, Germany
- Hannover Medical UniversityHannover, Germany
| | - Eckart Altenmüller
- Institute for Music Physiology and Musicians’ Medicine, University of Music, Drama and Media HannoverHannover, Germany
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Lee A, Tominaga K, Furuya S, Miyazaki F, Altenmüller E. Electrophysiological characteristics of task-specific tremor in 22 instrumentalists. J Neural Transm (Vienna) 2014; 122:393-401. [PMID: 25056709 DOI: 10.1007/s00702-014-1275-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/14/2014] [Indexed: 11/30/2022]
Abstract
Our aim was to address three characteristics of task-specific tremor in musicians (TSTM): First, we quantified muscular activity of flexor and extensor muscles, of coactivation as well as tremor acceleration. Second, we compared muscular activity between task-dependent and position-dependent tremor. Third, we investigated, whether there is an overflow of muscular activity to muscles adjacent to the affected muscles in TSTM. Tremor acceleration and muscular activity were measured in the affected muscles and the muscles adjacent to the affected muscles in 22 patients aged 51.5 ± 11.4 years with a task-specific tremor. We assessed power of muscular oscillatory activity and calculated the coherence between EMG activity of affected muscles and tremor acceleration as well as between adjacent muscles and tremor acceleration. This was done for task-dependent and position-dependent tremor. We found the highest power and coherence of muscular oscillatory activity in the frequency range of 3-8 Hz for affected and adjacent muscles. No difference was found between task-dependent and position-dependent tremor in neither power nor coherence measures. Our results generalize previous results of a relation between coactivation and tremor among a variety of musicians. Furthermore, we found coherence of adjacent muscles and TSTM. This indicates that overflow exists in TSTM and suggests an association of TST with dystonia.
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Affiliation(s)
- André Lee
- Institute of Music Physiology and Musicians' Medicine, Hannover University of Music, Drama and Media, Hannover, Germany,
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Analysis of dystonic tremor in musicians using empirical mode decomposition. Clin Neurophysiol 2014; 126:147-53. [PMID: 24845599 DOI: 10.1016/j.clinph.2014.04.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/18/2014] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Test the hypotheses that tremor amplitude in musicians with task-specific dystonia is higher at the affected finger (dystonic tremor, DT) or the adjacent finger (tremor associated with dystonia, TAD) than (1) in matched fingers of healthy musicians and non-musicians and (2) within patients in the unaffected and non-adjacent fingers of the affected side within patients. METHODS We measured 21 patients, 21 healthy musicians and 24 non-musicians. Participants exerted a flexion-extension movement. Instantaneous frequency and amplitude values were obtained with empirical mode decomposition and a Hilbert-transform, allowing to compare tremor amplitudes throughout the movement at various frequency ranges. RESULTS We did not find a significant difference in tremor amplitude between patients and controls for either DT or TAD. Neither differed tremor amplitude in the within-patient comparisons. CONCLUSION Both hypotheses were rejected and apparently neither DT nor TAD occur in musician's dystonia of the fingers. SIGNIFICANCE This is the first study assessing DT and TAD in musician's dystonia. Our finding suggests that even though MD is an excellent model for malplasticity due to excessive practice, it does not seem to provide a good model for DT. Rather it seems that musician's dystonia may manifest itself either as dystonic cramping without tremor or as task-specific tremor without overt dystonic cramping.
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Pita Lobo P, Quattrocchi G, Jutras MF, Sangla S, Apartis E, Vidailhet M, Grabli D. Primary writing tremor and writer's cramp: two faces of a same coin? Mov Disord 2013; 28:1306-7. [PMID: 23401238 DOI: 10.1002/mds.25340] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 09/09/2012] [Indexed: 11/10/2022] Open
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Kern KU, Kohl M, Seifert U, Schlereth T. Wirkung von Botulinumtoxin Typ B auf Stumpfschwitzen und Stumpfschmerzen. Schmerz 2012; 26:176-84. [DOI: 10.1007/s00482-011-1140-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Writer's cramp is a rare movement disorder of unknown etiology, in which a cramp is elicited primarily or exclusively with writing. We describe a patient with primary writer's cramp that was completely improved by drinking a small amount of alcohol. Although it is unclear how "alcohol" ameliorated the dystonia, this case suggests that alcohol might reverse the pathophysiologic changes in the entire basal ganglia circuit. In addition, we cannot rule out the possibility that the anxiolytic influence of alcohol may contribute to the beneficial effects on dystonia.
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Affiliation(s)
- Sung-Chul Lim
- Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea
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Palomar FJ, Mir P. Neurophysiological changes after intramuscular injection of botulinum toxin. Clin Neurophysiol 2011; 123:54-60. [PMID: 22051548 DOI: 10.1016/j.clinph.2011.05.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Revised: 05/13/2011] [Accepted: 05/14/2011] [Indexed: 11/29/2022]
Abstract
Botulinum toxin (BT) acts peripherally by inhibiting acetylcholine release from the presynaptic neuromuscular terminals and by weakening muscle contraction. Therefore, its clinical benefit is primarily due to its peripheral action. As a result, local injection of BT has become a successful and safe tool in the treatment of several neurological and non-neurological disorders. Studies in animals have also shown that the toxin can be retrogradely transported and even transcytosed to neurons in the central nervous system (CNS). Further human studies have suggested that BT could alter the functional organisation of the CNS indirectly through peripheral mechanisms. BT can interfere with and modify spinal, brainstem and cortical circuits, including cortical excitability and plasticity/organisation by altering spindle afferent inflow directed to spinal motoneurons or to the various cortical areas. It is well demonstrated that the distant CNS effects of BT treatment parallel the peripheral effect, although there is limited evidence as to the cause of this. Therefore, further studies focussed on central changes after BT treatment is needed for a better understanding of these non-peripheral effects of BT.
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Affiliation(s)
- Francisco J Palomar
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
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Abstract
Task-specific tremor is a form of action tremor that occurs only or mainly when a person is performing a specific skilled task. The most frequently encountered form of task-specific tremor is primary writing tremor (PWT). Currently, there is debate about whether PWT is a variant of essential tremor, writer's cramp (dystonia), a separate entity, or in some cases related to essential tremor and in others to dystonia. PWT typically occurs at a frequency of 5-7Hz and has been subdivided into to two types: Type A, task-induced tremor, and type B, positionally sensitive tremor. Temporary suppression of the tremor by alcohol is seen in about one-third of cases. There are no randomized controlled therapeutic studies involving patients with PWT, although anecdotal reports of beneficial responses to propranolol, primidone, anticholinergics, botulinum toxin treatment, and stereotactic surgery have been reported. Reciprocal inhibition of the H-reflex and intracortical excitability are normal in PWT, unlike writer's cramp. Hyperactivity in the cerebellar hemispheres has been demonstrated with positron emission tomography in PWT. Other task-specific tremors have been described but have not been studied in detail.
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Affiliation(s)
- Peter G Bain
- Department of Medicine, Imperial College School of Medicine, Charing Cross Hospital Campus, London, UK.
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Hai C, Yu-ping W, Hua W, Ying S. Advances in primary writing tremor. Parkinsonism Relat Disord 2010; 16:561-5. [DOI: 10.1016/j.parkreldis.2010.06.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 06/17/2010] [Accepted: 06/18/2010] [Indexed: 10/19/2022]
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Meunier S, Bleton JP, Mazevet D, Sangla S, Grabli D, Roze E, Vidailhet M. TENS is harmful in primary writing tremor. Clin Neurophysiol 2010; 122:171-5. [PMID: 20634131 DOI: 10.1016/j.clinph.2010.06.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 06/01/2010] [Accepted: 06/04/2010] [Indexed: 11/17/2022]
Abstract
OBJECTIVE It is unclear whether primary writing tremor (PWT) is a tremulous form of dystonia or a tremor per se. Transcutaneous electrical nerve stimulation (TENS) at 50 Hz applied for 2 weeks was reported to improve the writing capabilities of patients with writer's cramp (WC). We explored whether such a beneficial effect can be obtained in patients with a PWT. METHODS In a cross-over, double-blinded randomized study we tested whether 2-week periods of 5, 25 or 50 Hz TENS applied to wrist flexor muscles, improved the score of the Fahn-Tolosa-Marin scale of nine patients with PWT. Excitability of neurons and of various intracortical circuits in the motor cortex were also tested before and after TENS by using transcranial magnetic stimulation. RESULTS TENS at 5 and 25 Hz did not have any effect while TENS at 50 Hz worsened the clinical condition and the cortical excitability. CONCLUSIONS TENS is not a new treatment alternative for PWT. SIGNIFICANCE The beneficial effect in WC and the harmful one in PWT of TENS stresses that the two disorders are likely different nosological entities.
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Affiliation(s)
- S Meunier
- CRICM, INSERM UMR_S 975, CNRS UMR 7225, Paris F-75013, France
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McKenzie AL, Goldman S, Barrango C, Shrime M, Wong T, Byl N. Differences in physical characteristics and response to rehabilitation for patients with hand dystonia: musicians' cramp compared to writers' cramp. J Hand Ther 2009; 22:172-81; quiz 182. [PMID: 19389604 DOI: 10.1016/j.jht.2008.12.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 12/30/2008] [Accepted: 12/30/2008] [Indexed: 02/03/2023]
Abstract
STUDY DESIGN Pre-Post, Mixed Factorial Trial. INTRODUCTION Focal hand dystonia is a challenging movement disorder to rehabilitate in musicians and writers. PURPOSE OF THE STUDY To compare the neuromusculoskeletal characteristics of those with writers' cramp (WC) and musicians' cramp (MC), and evaluate responsiveness to learning-based sensorimotor training. METHODS Twenty-seven individuals (14 musicians, 13 writers) participated in 8 weeks of supervised therapy supplemented with a home program. Between-group differences on measures of musculoskeletal (physical), sensory, and motor performance were evaluated at baseline and post-intervention. RESULTS Subjects with MC had a higher level of functional independence and better range of motion, but less strength in the affected upper limb than those of subjects with WC. Subjects with MC demonstrated greater accuracy on graphesthesia, kinesthesia, and localization at baseline. No between-group differences in motor performance were noted at baseline or post-intervention. Following individually adapted learning-based sensorimotor training, both groups improved in musculoskeletal (physical) parameters, sensory processing, and motor control; however, improvements on certain subtests differed by group. At follow-up, differences in posture, ROM, strength, graphesthesia, and kinesthesia persisted between the groups. CONCLUSIONS Subjects with WC have different physical and performance risk factors compared with those of subjects with MC. Intervention paradigms are efficacious, but variable responses to rehabilitation occur.
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Affiliation(s)
- Alison L McKenzie
- Department of Physical Therapy, Chapman University, One University Drive, Orange, California 92624, USA
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Abstract
Botulinum toxin type A (BoNT-A) acts peripherally by inhibiting acetylcholine release from the presynaptic neuromuscular terminals, thus weakening muscle contraction, and its clinical benefit depends primarily on the toxin's peripheral action. In addition to acting directly at the neuromuscular junction, the toxin alters sensory inputs to the central nervous system, thus indirectly inducing secondary central changes. Some of the long-term clinical benefits of BoNT-A treatment may also reflect plastic changes in motor output after the reorganization of synaptic density.
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Affiliation(s)
- G Abbruzzese
- Dipartimento di Neuroscienze, Oftalmologia e Genetica, Universitá di Genova, Italia
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Yoon JH, Yong SW, Yong SW, Lee PH. Dystonic hand tremor in a patient with Wernicke encephalopathy. Parkinsonism Relat Disord 2008; 15:479-81. [PMID: 19038570 DOI: 10.1016/j.parkreldis.2008.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Revised: 10/13/2008] [Accepted: 10/20/2008] [Indexed: 10/21/2022]
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Ragothaman M, Swaminath PV, Pal PK, Muthane UB. Embouchure dystonia and tremor in a professional windpipe “Nadaswaram” player. Mov Disord 2007; 22:2133-5. [PMID: 17712852 DOI: 10.1002/mds.21709] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Labyt E, Houdayer E, Cassim F, Bourriez JL, Derambure P, Devanne H. Motor representation areas in epileptic patients with focal motor seizures: A TMS study. Epilepsy Res 2007; 75:197-205. [PMID: 17628428 DOI: 10.1016/j.eplepsyres.2007.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2007] [Revised: 05/25/2007] [Accepted: 06/04/2007] [Indexed: 11/18/2022]
Abstract
PURPOSE This study used TMS mapping to investigate the motor representation of the abductor pollicis brevis (APB) muscles in a group of patients with focal epilepsy originating in central or pre-central region. METHODS Eight epileptic patients and eight control subjects participated in the study. The coil was moved in 1.5-cm steps along a grid drawn on the subject's skull over the motor cortex of both hemispheres. At each site, six APB motor responses (evoked by TMS at 1.2 times the resting motor threshold) were recorded and averaged. The peak-to-peak amplitude was measured and plotted against the mediolateral and anteroposterior coil positions. The area of each APB muscle representation was measured and the position of the optimal point was calculated. RESULTS The resting motor threshold was increased bilaterally in epileptic patients. The maps were distorted in most patients (but not in control subjects), as evidenced by an off-centre optimal point. Interhemispheric differences in APB map areas were greater in patients than in control subjects. However, whether these increases in map area were on the epileptic side or on healthy side depended on the given subject. CONCLUSIONS The changes in APB representation observed in epileptic patients demonstrate that reorganization occurs within the motor cortex. The heterogeneity of the present results is probably related to different locations of the epileptogenic and/or lesional areas and to a variety of compensatory phenomena that may occur, notably with respect to the disease duration.
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Affiliation(s)
- E Labyt
- Department of Clinical Neurophysiology, EA 2683, R. Salengro Hospital, Lille University Medical Centre, F-59037 Lille, France.
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Trompetto C, Buccolieri A, Bove M, Brichetto G, Avanzino L, Marinelli L, Abbruzzese G. Bilateral impairment of intracortical inhibition in delayed-onset posthemiplegic dystonia: pathophysiological implications. Clin Neurophysiol 2006; 117:1312-8. [PMID: 16678482 DOI: 10.1016/j.clinph.2006.03.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 03/09/2006] [Accepted: 03/17/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To study short interval intracortical inhibition (SICI) in a rare patient with segmental dystonia of the left upper limb due to a vascular lesion in the contralateral putamen without corticospinal tract involvement. METHODS Paired-pulse transcranial magnetic stimulation (TMS) was applied to both hemispheres in a conditioning-test paradigm. Six interstimulus intervals (ISIs) and 4 conditioning stimulation intensities were investigated in two separate sessions. RESULTS Motor evoked potentials upon single-pulse TMS were within the normal range, whereas paired-pulse TMS revealed major changes in cortical excitability, proving that SICI was bilaterally absent. CONCLUSIONS The bilateral impairment of SICI cannot be considered the cause of dystonic contractions, but just a predisposing factor. SIGNIFICANCE The absence of SICI might be regarded as a condition able to promote maladaptive plastic changes triggered by focal lesions in the putamen.
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Affiliation(s)
- Carlo Trompetto
- Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Via de Toni, 5, 16132 Genova, Italy
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Ljubisavljevic M, Kacar A, Milanovic S, Svetel M, Kostic VS. Changes in cortical inhibition during task-specific contractions in primary writing tremor patients. Mov Disord 2006; 21:855-9. [PMID: 16482535 DOI: 10.1002/mds.20807] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Primary writing tremor (PWT) is a rare disease of unknown pathophysiology. We studied changes in silent period (SP) duration, after transcranial magnetic stimulation (TMS), set at 20% above the motor threshold in 6 PWT patients and 7 healthy control subjects. SP duration was tested during a task-specific act, i.e., writing that induced tremor in all patients in the affected hand (Wr); nonspecific voluntary contraction of intensity, matching that developed during writing (VCWr); and during near maximal voluntary contraction (VCNmax). There were no differences in SP duration during Wr and VCWr contraction on the right affected side or between sides in both PWT patients and control subjects, nor between the groups. However, during VCNmax, SP significantly shortened on both sides in PWT patients, whereas there were no changes in control subjects. Although it appears that inhibitory mechanism are not directly involved in the generation of the tremulous activity, the shortening of SP indicates that central inhibitory mechanisms are affected in PWT patients. Therefore, whereas the underlying pathophysiological mechanisms in PWT and writer's cramp may share common features, the results indicate that PWT is not a variant of focal task-specific dystonia but rather a separate nosological entity.
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Affiliation(s)
- Milos Ljubisavljevic
- Laboratory for Neurophysiology, Institute for Medical Research, Belgrade, Serbia.
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