1
|
Marques Paulo AJ, Sato JR, de Faria DD, Balardin J, Borges V, de Azevedo Silva SM, Ballalai Ferraz H, de Carvalho Aguiar P. Task-related brain activity in upper limb dystonia revealed by simultaneous fNIRS and EEG. Clin Neurophysiol 2024; 159:1-12. [PMID: 38232654 DOI: 10.1016/j.clinph.2023.12.008] [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: 03/10/2023] [Revised: 11/21/2023] [Accepted: 12/12/2023] [Indexed: 01/19/2024]
Abstract
OBJECTIVE The aim of this study was to explore differences in brain activity and connectivity using simultaneous electroencephalography and near-infrared spectroscopy in patients with focal dystonia during handwriting and finger-tapping tasks. METHODS Patients with idiopathic right upper limb focal dystonia and controls were assessed by simultaneous near-infrared spectroscopy and electroencephalography during the writing and finger-tapping tasks in terms of the mu-alpha, mu-beta, beta and low gamma power and effective connectivity, as well as relative changes in oxyhemoglobin (oxy-Hb) and deoxyhemoglobin using a channel-wise approach with a mixed-effect model. RESULTS Patients exhibited higher oxy-Hb levels in the right and left motor cortex and supplementary motor area during writing, but lower oxy-Hb levels in the left sensorimotor and bilateral somatosensory area during finger-tapping compared to controls. During writing, patients showed increased low gamma power in the bilateral sensorimotor cortex and less mu-beta and beta attenuation compared to controls. Additionally, patients had reduced connectivity between the supplementary motor area and the left sensorimotor cortex during writing. No differences were observed in terms of effective connectivity in either task. Finally, patients failed to attenuate the mu-alpha, mu-beta, and beta rhythms during the finger-tapping task. CONCLUSIONS Cortical blood flow and EEG spectral power differ between controls and dystonia patients, depending on the task. Writing increased blood flow and altered connectivity in dystonia patients, and it also decreased slow-band attenuation. Finger-tapping decreased blood flow and slow-band attenuation. SIGNIFICANCE Simultaneous fNIRS and EEG may show relevant information regarding brain dynamics in movement disorders patients in unconstrained environments.
Collapse
Affiliation(s)
- Artur José Marques Paulo
- Hospital Israelita Albert Einstein, Instituto de Ensino e Pesquisa, Av. Albert Einstein, 627, São Paulo-SP 05652-900, Brazil
| | - João Ricardo Sato
- Hospital Israelita Albert Einstein, Instituto de Ensino e Pesquisa, Av. Albert Einstein, 627, São Paulo-SP 05652-900, Brazil; Universidade Federal do ABC, Centro de Matemática Computação e Cognição , São Bernardo do Campo-SP , 09606-045, Brazil
| | - Danilo Donizete de Faria
- Universidade Federal de São Paulo, Department of Neurology and Neurosurgery, R. Pedro de Toledo, 650, São Paulo - SP 04039-002, Brazil; Hospital do Servidor Público Estadual, Av. Ibirapuera, 981 - Vila Clementino, São Paulo - SP 04038-034, Brazil
| | - Joana Balardin
- Hospital Israelita Albert Einstein, Instituto de Ensino e Pesquisa, Av. Albert Einstein, 627, São Paulo-SP 05652-900, Brazil
| | - Vanderci Borges
- Universidade Federal de São Paulo, Department of Neurology and Neurosurgery, R. Pedro de Toledo, 650, São Paulo - SP 04039-002, Brazil
| | - Sonia Maria de Azevedo Silva
- Universidade Federal de São Paulo, Department of Neurology and Neurosurgery, R. Pedro de Toledo, 650, São Paulo - SP 04039-002, Brazil; Hospital do Servidor Público Estadual, Av. Ibirapuera, 981 - Vila Clementino, São Paulo - SP 04038-034, Brazil
| | - Henrique Ballalai Ferraz
- Universidade Federal de São Paulo, Department of Neurology and Neurosurgery, R. Pedro de Toledo, 650, São Paulo - SP 04039-002, Brazil
| | - Patrícia de Carvalho Aguiar
- Hospital Israelita Albert Einstein, Instituto de Ensino e Pesquisa, Av. Albert Einstein, 627, São Paulo-SP 05652-900, Brazil; Universidade Federal de São Paulo, Department of Neurology and Neurosurgery, R. Pedro de Toledo, 650, São Paulo - SP 04039-002, Brazil.
| |
Collapse
|
2
|
Funk AT, Hassan AAO, Brüggemann N, Sharma N, Breiter HC, Blood AJ, Waugh JL. In humans, striato-pallido-thalamic projections are largely segregated by their origin in either the striosome-like or matrix-like compartments. Front Neurosci 2023; 17:1178473. [PMID: 37954873 PMCID: PMC10634229 DOI: 10.3389/fnins.2023.1178473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 09/04/2023] [Indexed: 11/14/2023] Open
Abstract
Cortico-striato-thalamo-cortical (CSTC) loops are fundamental organizing units in mammalian brains. CSTCs process limbic, associative, and sensorimotor information in largely separated but interacting networks. CTSC loops pass through paired striatal compartments, striosome (aka patch) and matrix, segregated pools of medium spiny projection neurons with distinct embryologic origins, cortical/subcortical structural connectivity, susceptibility to injury, and roles in behaviors and diseases. Similarly, striatal dopamine modulates activity in striosome and matrix in opposite directions. Routing CSTCs through one compartment may be an anatomical basis for regulating discrete functions. We used differential structural connectivity, identified through probabilistic diffusion tractography, to distinguish the striatal compartments (striosome-like and matrix-like voxels) in living humans. We then mapped compartment-specific projections and quantified structural connectivity between each striatal compartment, the globus pallidus interna (GPi), and 20 thalamic nuclei in 221 healthy adults. We found that striosome-originating and matrix-originating streamlines were segregated within the GPi: striosome-like connectivity was significantly more rostral, ventral, and medial. Striato-pallido-thalamic streamline bundles that were seeded from striosome-like and matrix-like voxels transited spatially distinct portions of the white matter. Matrix-like streamlines were 5.7-fold more likely to reach the GPi, replicating animal tract-tracing studies. Striosome-like connectivity dominated in six thalamic nuclei (anteroventral, central lateral, laterodorsal, lateral posterior, mediodorsal-medial, and medial geniculate). Matrix-like connectivity dominated in seven thalamic nuclei (centromedian, parafascicular, pulvinar-anterior, pulvinar-lateral, ventral lateral-anterior, ventral lateral-posterior, ventral posterolateral). Though we mapped all thalamic nuclei independently, functionally-related nuclei were matched for compartment-level bias. We validated these results with prior thalamostriate tract tracing studies in non-human primates and other species; where reliable data was available, all agreed with our measures of structural connectivity. Matrix-like connectivity was lateralized (left > right hemisphere) in 18 thalamic nuclei, independent of handedness, diffusion protocol, sex, or whether the nucleus was striosome-dominated or matrix-dominated. Compartment-specific biases in striato-pallido-thalamic structural connectivity suggest that routing CSTC loops through striosome-like or matrix-like voxels is a fundamental mechanism for organizing and regulating brain networks. Our MRI-based assessments of striato-thalamic connectivity in humans match and extend the results of prior tract tracing studies in animals. Compartment-level characterization may improve localization of human neuropathologies and improve neurosurgical targeting in the GPi and thalamus.
Collapse
Affiliation(s)
- Adrian T. Funk
- Division of Pediatric Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, United States
| | - Asim A. O. Hassan
- Department of Natural Sciences and Mathematics, University of Texas at Dallas, Richardson, TX, United States
| | - Norbert Brüggemann
- Department of Neurology and Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Nutan Sharma
- Department of Neurology, Massachusetts General Hospital, Harvard University, Boston, MA, United States
| | - Hans C. Breiter
- Laboratory of Neuroimaging and Genetics, Massachusetts General Hospital, Charlestown, MA, United States
- Warren Wright Adolescent Center, Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Anne J. Blood
- Laboratory of Neuroimaging and Genetics, Massachusetts General Hospital, Charlestown, MA, United States
- Department of Psychiatry, Massachusetts General Hospital, Harvard University, Boston, MA, United States
- Mood and Motor Control Laboratory, Massachusetts General Hospital, Charlestown, MA, United States
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States
| | - Jeff L. Waugh
- Division of Pediatric Neurology, Department of Pediatrics, University of Texas Southwestern, Dallas, TX, United States
- Mood and Motor Control Laboratory, Massachusetts General Hospital, Charlestown, MA, United States
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States
| |
Collapse
|
3
|
Maamary J, Peters J, Kyle K, Ruge D, Jonker B, Barnett Y, Tisch S. Evaluation of the efficacy and safety of MRI-guided focused ultrasound (MRgFUS) for focal hand dystonia: study protocol for an open-label non-randomised clinical trial. BMJ Neurol Open 2023; 5:e000522. [PMID: 37900622 PMCID: PMC10603452 DOI: 10.1136/bmjno-2023-000522] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 09/23/2023] [Indexed: 10/31/2023] Open
Abstract
Introduction MRI-guided focused ultrasound (MRgFUS) thalamotomy provides an exciting development in the field of minimally invasive stereotactic neurosurgery. Current treatment options for focal hand dystonia are limited, with potentially more effective invasive stereotactic interventions, such as deep brain stimulation or lesional therapies, rarely used. The advent of minimally invasive brain lesioning provides a potentially safe and effective treatment approach with a recent pilot study establishing MRgFUS Vo-complex thalamotomy as an effective treatment option for focal hand dystonia. In this study, we undertake an open-label clinical trial to further establish MRgFUS Vo-complex thalamotomy as an effective treatment for focal hand dystonia with greater attention paid to potential motor costs associated with this treatment. To elucidate pathophysiology of dystonia and treatment mechanisms, neurophysiological and MRI analysis will be performed longitudinally to explore the hypothesis that neuroplastic and structural changes that may underlie this treatment benefit. Methods and analysis A total of 10 participants will be recruited into this open-label clinical trial. All participants will undergo clinical, kinemetric, neurophysiological and radiological testing at baseline, followed by repeated measures at predesignated time points post MRgFUS Vo-complex thalamotomy. Further, to identify any underlying structural or neurophysiological abnormalities present in individuals with focal hand dystonia, 10 age and gender matched control participants will be recruited to undergo comparative investigation. These results will be compared with the intervention participants both at baseline and at 12 months to assess for normalisation of these abnormalities, if present. Ethics and dissemination This trial was reviewed and approved by the St Vincent's Health Network Sydney Human Research Ethics Committee (2022/ETH00778). Study results will be published in peer-reviewed journals and presented at both national and international conferences. Trial registration number CTRN12622000775718.
Collapse
Affiliation(s)
- Joel Maamary
- Department of Neurology, St Vincent's Health Australia Ltd, Sydney, New South Wales, Australia
- School of Clinical Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - James Peters
- Department of Neurology, St Vincent's Health Australia Ltd, Sydney, New South Wales, Australia
- School of Clinical Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Kain Kyle
- Brain and Mind Centre, The University of Sydney, Sydney, New South Wales, Australia
| | - Diane Ruge
- Laboratoire de Recherche en Neurosciences Cliniques, Montpellier, France
| | - Benjamin Jonker
- Department of Neurosurgery, St Vincent's Health Australia Ltd, Sydney, New South Wales, Australia
| | - Yael Barnett
- Department of Radiology, St Vincent's Health Australia Ltd, Sydney, New South Wales, Australia
| | - Stephen Tisch
- Department of Neurology, St Vincent's Health Australia Ltd, Sydney, New South Wales, Australia
| |
Collapse
|
4
|
Kuster JK, Levenstein JM, Waugh J, Multhaupt-Buell TJ, Lee MJ, Kim BW, Pagnacco G, Makhlouf ML, Sudarsky LR, Breiter HC, Sharma N, Blood AJ. Sustained activation in basal ganglia and cerebellum after repetitive movement in a non-task-specific dystonia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.19.533030. [PMID: 36993354 PMCID: PMC10055227 DOI: 10.1101/2023.03.19.533030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
We previously observed sustained fMRI BOLD signal in the basal ganglia in focal hand dystonia patients after a repetitive finger tapping task. Since this was observed in a task-specific dystonia, for which excessive task repetition may play a role in pathogenesis, in the current study we asked if this effect would be observed in a focal dystonia (cervical dystonia [CD]) that is not considered task-specific or thought to result from overuse. We evaluated fMRI BOLD signal time courses before, during, and after the finger tapping task in CD patients. We observed patient/control differences in post-tapping BOLD signal in left putamen and left cerebellum during the non-dominant (left) hand tapping condition, reflecting abnormally sustained BOLD signal in CD. BOLD signals in left putamen and cerebellum were also abnormally elevated in CD during tapping itself and escalated as tapping was repeated. There were no cerebellar differences in the previously studied FHD cohort, either during or after tapping. We conclude that some elements of pathogenesis and/or pathophysiology associated with motor task execution/repetition may not be limited to task-specific dystonias, but there may be regional differences in these effects across dystonias, associated with different types of motor control programs.
Collapse
|
5
|
Blood AJ. De-anthropomorphizing brain mapping: How a “component” perspective unbounded by behavioral categories may reconcile localization vs. circuit-based models of brain function. Front Syst Neurosci 2022; 16:946715. [PMID: 35965999 PMCID: PMC9363603 DOI: 10.3389/fnsys.2022.946715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/30/2022] [Indexed: 12/03/2022] Open
|
6
|
Di Pietro M, Russo M, Dono F, Carrarini C, Thomas A, Di Stefano V, Telese R, Bonanni L, Sensi SL, Onofrj M, Franciotti R. A Critical Review of Alien Limb-Related Phenomena and Implications for Functional Magnetic Resonance Imaging Studies. Front Neurol 2021; 12:661130. [PMID: 34566830 PMCID: PMC8458742 DOI: 10.3389/fneur.2021.661130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 07/06/2021] [Indexed: 11/27/2022] Open
Abstract
Consensus criteria on corticobasal degeneration (CBD) include alien limb (AL) phenomena. However, the gist of the behavioral features of AL is still “a matter of debate.” CBD-related AL has so far included the description of involuntary movements, frontal release phenomena (frontal AL), or asomatognosia (posterior or “real” AL). In this context, the most frequent symptoms are language and praxis deficits and cortical sensory misperception. However, asomatognosia requires, by definition, intact perception and cognition. Thus, to make a proper diagnosis of AL in the context of CBD, cognitive and language dysfunctions must be carefully verified and objectively assessed. We reviewed the current literature on AL in CBD and now propose that the generic use of the term AL should be avoided. This catchall AL term should instead be deconstructed. We propose that the term AL is appropriate to describe clinical features associated with specific brain lesions. More discrete sets of regionally bound clinical signs that depend on dysfunctions of specific brain areas need to be assessed and presented when posing the diagnosis. Thus, in our opinion, the AL term should be employed in association with precise descriptions of the accompanying involuntary movements, sensory misperceptions, agnosia-asomatognosia contents, and the presence of utilization behavior. The review also offers an overview of functional magnetic resonance imaging-based studies evaluating AL-related phenomena. In addition, we provide a complementary set of video clips depicting CBD-related involuntary movements that should not mistakenly be interpreted as signs of AL.
Collapse
Affiliation(s)
- Martina Di Pietro
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Mirella Russo
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Fedele Dono
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Claudia Carrarini
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Astrid Thomas
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Vincenzo Di Stefano
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Department of Biomedicine, Neuroscience and Advanced Diagnostic (BiND), University of Palermo, Palermo, Italy
| | - Roberta Telese
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,IRCCS C. Mondino Foundation, Pavia, Italy
| | - Laura Bonanni
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Stefano L Sensi
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Marco Onofrj
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy.,YDA Foundation, Institute of Immune Therapy and Advanced Biological Treatment, Pescara, Italy
| | - Raffaella Franciotti
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy
| |
Collapse
|
7
|
Kita K, Furuya S, Osu R, Sakamoto T, Hanakawa T. Aberrant Cerebello-Cortical Connectivity in Pianists With Focal Task-Specific Dystonia. Cereb Cortex 2021; 31:4853-4863. [PMID: 34013319 DOI: 10.1093/cercor/bhab127] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Musician's dystonia is a type of focal task-specific dystonia (FTSD) characterized by abnormal muscle hypercontraction and loss of fine motor control specifically during instrument playing. Although the neuropathophysiology of musician's dystonia remains unclear, it has been suggested that maladaptive functional abnormalities in subcortical and cortical regions may be involved. Here, we hypothesized that aberrant effective connectivity between the cerebellum (subcortical) and motor/somatosensory cortex may underlie the neuropathophysiology of musician's dystonia. Using functional magnetic resonance imaging, we measured the brain activity of 30 pianists with or without FTSD as they played a magnetic resonance imaging-compatible piano-like keyboard, which elicited dystonic symptoms in many but not all pianists with FTSD. Pianists with FTSD showed greater activation of the right cerebellum during the task than healthy pianists. Furthermore, patients who reported dystonic symptoms during the task demonstrated greater cerebellar activation than those who did not, establishing a link between cerebellar activity and overt dystonic symptoms. Using multivoxel pattern analysis, moreover, we found that dystonic and healthy pianists differed in the task-related effective connectivity between the right cerebellum and left premotor/somatosensory cortex. The present study indicates that abnormal cerebellar activity and cerebello-cortical connectivity may underlie the pathophysiology of FTSD in musicians.
Collapse
Affiliation(s)
- Kahori Kita
- Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan.,Center for Frontier Medical Engineering, Chiba University, Chiba 263-8522, Japan.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Shinichi Furuya
- Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan.,Musical Skill and Injury Center, Sophia University, Tokyo 102-8554, Japan.,Sony Computer Science Laboratories Inc., Tokyo 141-0022, Japan
| | - Rieko Osu
- Faculty of Human Sciences, Waseda University, Saitama 359-1192, Japan
| | - Takashi Sakamoto
- Department of Neurology, National Center of Neurology and Psychiatry Hospital, Tokyo 187-8551, Japan
| | - Takashi Hanakawa
- Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan.,Integrated Neuroanatomy and Neuroimaging, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| |
Collapse
|
8
|
Berman BD, Groth CL, Shelton E, Sillau SH, Sutton B, Legget KT, Tregellas JR. Hemodynamic responses are abnormal in isolated cervical dystonia. J Neurosci Res 2020; 98:692-703. [PMID: 31692015 PMCID: PMC7015799 DOI: 10.1002/jnr.24547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 10/10/2019] [Accepted: 10/10/2019] [Indexed: 01/04/2023]
Abstract
Neuroimaging studies using functional magnetic resonance imaging (fMRI), which measures brain activity by detecting the changes in blood oxygenation levels, are advancing our understanding of the pathophysiology of dystonia. Neurobiological disturbances in dystonia, however, may affect neurovascular coupling and impact the interpretability of fMRI studies. We evaluated here whether the hemodynamic response patterns during a behaviorally matched motor task are altered in isolated cervical dystonia (CD). Twenty-five CD patients and 25 healthy controls (HCs) underwent fMRI scanning during a paced finger tapping task (nondystonic task in patients). Imaging data were analyzed using a constrained principal component analysis-a statistical method that combines regression analysis and principal component analysis and enables the extraction of task-related functional networks and determination of the spatial and temporal hemodynamic response patterns associated with the task performance. Data from three patients and two controls were removed due to excessive movement. No significant differences in demographics or motor performance were observed. Three task-associated functional brain networks were identified. During task performance, reduced hemodynamic responses were seen in a sensorimotor network and in a network that included key nodes of the default mode, executive control and visual networks. During rest, reductions in hemodynamic responses were seen in the cognitive/visual network. Lower hemodynamic responses within the primary sensorimotor network in patients were correlated with the increased dystonia severity. Pathophysiological disturbances in isolated CD, such as alterations in inhibitory signaling and dopaminergic neurotransmission, may impact neurovascular coupling. Not accounting for hemodynamic response differences in fMRI studies of dystonia could lead to inaccurate results and interpretations.
Collapse
Affiliation(s)
- Brian D. Berman
- Department of Neurology, University of Colorado School of Medicine, Aurora, CO
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO
- Neurology Section, Denver VA Medical Center, Aurora, CO, USA
| | - Christopher L. Groth
- Department of Neurology, University of Colorado School of Medicine, Aurora, CO
- Department of Neurology, University of Iowa Hospitals and Clinics, Iowa City, IA
| | - Erica Shelton
- Department of Neurology, University of Colorado School of Medicine, Aurora, CO
| | - Stefan H. Sillau
- Department of Neurology, University of Colorado School of Medicine, Aurora, CO
| | - Brianne Sutton
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO
| | - Kristina T. Legget
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO
| | - Jason R. Tregellas
- Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO
- Research Service, Denver VA Medical Center, Aurora, CO USA
| |
Collapse
|
9
|
The neurobiological basis for novel experimental therapeutics in dystonia. Neurobiol Dis 2019; 130:104526. [PMID: 31279827 DOI: 10.1016/j.nbd.2019.104526] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 06/13/2019] [Accepted: 07/03/2019] [Indexed: 12/17/2022] Open
Abstract
Dystonia is a movement disorder characterized by involuntary muscle contractions, twisting movements, and abnormal postures that may affect one or multiple body regions. Dystonia is the third most common movement disorder after Parkinson's disease and essential tremor. Despite its relative frequency, small molecule therapeutics for dystonia are limited. Development of new therapeutics is further hampered by the heterogeneity of both clinical symptoms and etiologies in dystonia. Recent advances in both animal and cell-based models have helped clarify divergent etiologies in dystonia and have facilitated the identification of new therapeutic targets. Advances in medicinal chemistry have also made available novel compounds for testing in biochemical, physiological, and behavioral models of dystonia. Here, we briefly review motor circuit anatomy and the anatomical and functional abnormalities in dystonia. We then discuss recently identified therapeutic targets in dystonia based on recent preclinical animal studies and clinical trials investigating novel therapeutics.
Collapse
|
10
|
Desrochers P, Brunfeldt A, Sidiropoulos C, Kagerer F. Sensorimotor Control in Dystonia. Brain Sci 2019; 9:brainsci9040079. [PMID: 30979073 PMCID: PMC6523253 DOI: 10.3390/brainsci9040079] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/03/2019] [Accepted: 04/08/2019] [Indexed: 12/24/2022] Open
Abstract
This is an overview of the sensorimotor impairments in dystonia, a syndrome characterized by sustained or intermittent aberrant movement patterns leading to abnormal movements and/or postures with or without a tremulous component. Dystonia can affect the entire body or specific body regions and results from a plethora of etiologies, including subtle changes in gray and white matter in several brain regions. Research over the last 25 years addressing topics of sensorimotor control has shown functional sensorimotor impairments related to sensorimotor integration, timing, oculomotor and head control, as well as upper and lower limb control. In the context of efforts to update the classification of dystonia, sensorimotor research is highly relevant for a better understanding of the underlying pathology, and potential mechanisms contributing to global and regional dysfunction within the central nervous system. This overview of relevant research regarding sensorimotor control in humans with idiopathic dystonia attempts to frame the dysfunction with respect to what is known regarding motor control in patients and healthy individuals. We also highlight promising avenues for the future study of neuromotor control that may help to further elucidate dystonia etiology, pathology, and functional characteristics.
Collapse
Affiliation(s)
- Phillip Desrochers
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
| | - Alexander Brunfeldt
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
| | - Christos Sidiropoulos
- Dept. of Neurology and Ophthalmology, Michigan State University, East Lansing, MI 48824, USA.
| | - Florian Kagerer
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
| |
Collapse
|
11
|
Brodoehl S, Wagner F, Prell T, Klingner C, Witte OW, Günther A. Cause or effect: Altered brain and network activity in cervical dystonia is partially normalized by botulinum toxin treatment. NEUROIMAGE-CLINICAL 2019; 22:101792. [PMID: 30928809 PMCID: PMC6444302 DOI: 10.1016/j.nicl.2019.101792] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 03/14/2019] [Accepted: 03/24/2019] [Indexed: 01/17/2023]
Abstract
Background Idiopathic cervical dystonia (CD) is a chronic movement disorder characterized by impressive clinical symptoms and the lack of clear pathological findings in clinical diagnostics and imaging. At present, the injection of botulinum toxin (BNT) in dystonic muscles is an effective therapy to control motor symptoms and pain in CD. Objectives We hypothesized that, although it is locally injected to dystonic muscles, BNT application leads to changes in brain and network activity towards normal brain function. Methods Using 3 T functional MR imaging along with advanced analysis techniques (functional connectivity, Granger causality, and regional homogeneity), we aimed to characterize brain activity in CD (17 CD patients vs. 17 controls) and to uncover the effects of BNT treatment (at 6 months). Results In CD, we observed an increased information flow within the basal ganglia, the thalamus, and the sensorimotor cortex. In parallel, some of these structures became less responsive to regulating inputs. Furthermore, our results suggested an altered somatosensory integration. Following BNT administration, we noted a shift towards normal brain function in the CD patients, especially within the motor cortex, the somatosensory cortex, and the basal ganglia. Conclusion The changes in brain function and network activity in CD can be interpreted as related to the underlying cause, the effort to compensate or a mixture of both. Although BNT is applied in the last stage of the cortico-neuromuscular pathway, brain patterns are shifted towards those of healthy controls. we characterized brain activity in CD and the effects of BNT using 3T fMR imaging and network analysis techniques following treatment with botulinum toxin (BNT), abnormal brain activity patterns in primary dystonia are attenuated critical key regions for both the pathophysiology and BNT-induced improvement in cervical dystonia are the BG
Collapse
Affiliation(s)
- Stefan Brodoehl
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany.
| | - Franziska Wagner
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany
| | - Tino Prell
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Center for Healthy Aging, Jena University Hospital, Jena, Germany
| | - Carsten Klingner
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany
| | - O W Witte
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany; Center for Healthy Aging, Jena University Hospital, Jena, Germany
| | - Albrecht Günther
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany
| |
Collapse
|
12
|
Abstract
Even before the success of combined positron emission tomography and computed tomography (PET/CT), the neuroimaging community was conceiving the idea to integrate the positron emission tomography (PET), with very high molecular quantitative data but low spatial resolution, and magnetic resonance imaging (MRI), with high spatial resolution. Several technical limitations have delayed the use of a hybrid scanner in neuroimaging studies, including the full integration of the PET detector ring within the MRI system, the optimization of data acquisition, and the implementation of reliable methods for PET attenuation, motion correction, and joint image reconstruction. To be valid and useful in clinical and research settings, this instrument should be able to simultaneously acquire PET and MRI, and generate quantitative parametric PET images comparable to PET-CT. While post hoc co-registration of combined PET and MRI data acquired separately became the most reliable technique for the generation of "fused" PET-MRI images, only hybrid PET-MRI approach allows merging these measurements naturally and correlating them in a temporal manner. Furthermore, hybrid PET-MRI represents the most accurate tool to investigate in vivo the interplay between molecular and functional aspects of brain pathophysiology. Hybrid PET-MRI technology is still in the early stages in the movement disorders field, due to the limited availability of scanners with integrated optimized methodological models. This technology is ideally suited to investigate interactions between resting-state functional/arterial spin labeling MRI and [18F]FDG PET glucose metabolism in the evaluation of the brain "hubs" particularly vulnerable to neurodegeneration, areas with a high degree of connectivity and associated with an efficient synaptic neurotransmission. In Parkinson's disease, hybrid PET-MRI is also the ideal instrument to deeper explore the relationship between resting-state functional MRI and dopamine release at [11C]raclopride PET challenge, in the identification of early drug-naïve Parkinson's disease patients at higher risk of motor complications and in the evaluation of the efficacy of novel neuroprotective treatment able to restore at the same time the altered resting state and the release of dopamine. In this chapter, we discuss the key methodological aspects of hybrid PET-MRI; the evidence in movement disorders of the key resting-state functional and perfusion MRI; [18F]FDG PET and [11C]raclopride PET challenge studies; the potential advantages of using hybrid PET-MRI to investigate the pathophysiology of movement disorders and neurodegenerative diseases. Future directions of hybrid PET-MRI will be discussed alongside with up-to-date technological innovations on hybrid systems.
Collapse
|
13
|
Allgöwer K, Fürholzer W, Hermsdörfer J. Impaired performance of patients with writer's cramp in complex fine motor tasks. Clin Neurophysiol 2018; 129:2392-2402. [PMID: 30278388 DOI: 10.1016/j.clinph.2018.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 08/17/2018] [Accepted: 09/01/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE Writer's cramp (WC) is a task-specific focal dystonia. WC is characterized by involuntary contractions of muscles of the hand and arm during handwriting, resulting in impaired writing with exaggerated finger forces. The generalization of symptoms to other fine motor tasks is widely discussed. The aim of the study was to determine affected fine motor aspects with an extensive testing battery. METHODS Twelve people with WC and twelve healthy controls were examined. Performance in the Jebsen-Taylor Hand Function Test, Nine-Hole-Peg Test and 2-point discrimination was evaluated. To analyze object manipulation skills, we examined grip forces, temporal measures and other aspects of force control during (1) lifting actions with variations of weight and surface (2) cyclic movements (3) visuomotor tracking (4) fast force changes and (5) grip strength. In addition, correlation between the dependent variables of the fine motor tasks and the handwriting deficits was assessed. RESULTS WC patients had impaired performance in the visuomotor tracking task (root mean square error (RMSE), p = 0.03 and time lag, p = 0.05) and the fast force changes (frequency, p = 0.01). There were no statistically significant group differences in the other tasks. We found a correlation between the RMSE of the tracking task and the time needed to write the test sentence (r = 0.643, p = 0.01). CONCLUSION WC patients revealed abnormalities in complex fine motor performance in tasks with high demands on coordination and visual components, specifically in tracking and fast force changes. SIGNIFICANCE This suggests a deficit in visuomotor integration, coordination and cognitive aspects related to movement processing particularly with respect to low forces. These insights may prove useful in the development of targeted training approaches.
Collapse
Affiliation(s)
- Kathrin Allgöwer
- Technical University of Munich, Department of Sport and Health Sciences, Chair of Human Movement Science, Munich, Germany.
| | | | - Joachim Hermsdörfer
- Technical University of Munich, Department of Sport and Health Sciences, Chair of Human Movement Science, Munich, Germany
| |
Collapse
|
14
|
Kita K, Rokicki J, Furuya S, Sakamoto T, Hanakawa T. Resting-state basal ganglia network codes a motor musical skill and its disruption From dystonia. Mov Disord 2018; 33:1472-1480. [PMID: 30277603 PMCID: PMC6220822 DOI: 10.1002/mds.27448] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 05/01/2018] [Accepted: 05/03/2018] [Indexed: 11/06/2022] Open
Abstract
Background: Musician's dystonia critically impacts professional musicians' careers as they may lose musical skills, which have been acquired through long and intensive training. Yet the pathophysiology of musician's dystonia and its link to the neural mechanisms supporting musical skills is poorly understood. We tested if resting‐state functional connectivity might reflect an aspect of musical skill linked to the pathophysiology of musician's dystonia. We also tested a second hypothesis that the region with altered resting‐state functional connectivity might be correlated with a quantitative measure of musical skills. Methods: We studied 21 patients with musician's dystonia affecting their hands and 34 healthy musicians, using resting‐state functional magnetic resonance imaging and behavioral assessment. We tested between‐group differences of resting‐state functional connectivity throughout the whole brain using independent component analysis. Results: We found abnormal basal ganglia resting‐state functional connectivity in the putamina of patients with musician's dystonia compared with those of healthy musicians (P = 0.035 corrected for multiple comparisons). We also found that the temporal precision of keystrokes was correlated with basal ganglia functional connectivity in the putamina of healthy pianists (r = 0.72, P = 0.0005), but not in pianists with musician's dystonia (r = −0.11, P = 0.64). Conclusions: We show that abnormalities of the putamen exist even at rest in musician's dystonia, whereas putaminal abnormality has previously been reported during a task. Moreover, basal ganglia resting‐state functional connectivity in the putamen represented training levels in healthy musicians, and its disruption was associated with musician's dystonia. This novel finding hints at the pathophysiological mechanisms by which musician's dystonia follows extensive musical training. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Kahori Kita
- Center for Frontier Medical Engineering, Chiba University, Chiba, Japan.,Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Jaroslav Rokicki
- NORMENT, KG Jebsen Centre for Psychosis Research, Department of Psychology, University of Oslo, Oslo, Norway.,Department of Clinical Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Shinichi Furuya
- Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan.,Musical Skill and Injury Center, Sophia University, Tokyo, Japan.,Sony Computer Science Laboratories, Tokyo, Japan
| | - Takashi Sakamoto
- Department of Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Takashi Hanakawa
- Department of Advanced Neuroimaging, Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| |
Collapse
|
15
|
Berndt M, Li Y, Gora-Stahlberg G, Jochim A, Haslinger B. Impaired white matter integrity between premotor cortex and basal ganglia in writer's cramp. Brain Behav 2018; 8:e01111. [PMID: 30239158 PMCID: PMC6192408 DOI: 10.1002/brb3.1111] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 08/03/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Writer's cramp (WC) as a focal hand dystonia is characterized by abnormal postures of the hand during writing. Impaired inhibition and maladaptive plasticity in circuits linking the basal ganglia and sensorimotor cortices have been described. In particular, a dysfunction of lateral premotor cortices has been associated with impaired motor control in WC. We applied diffusion tensor imaging to identify changes in white matter connectivity between premotor regions and important cortical and subcortical structures. METHODS Whole brain white matter tracts were reconstructed in 18 right-handed WC patients and 18 matched controls, using probabilistic fiber tracking. We restricted our analyses to left-hemispheric fibers between the middle frontal gyrus (MFG) and basal ganglia, thalamus, primary motor, and sensory cortex. Diffusion parameters (fractional anisotropy and linear anisotropy) were compared between both groups. RESULTS A significant reduction in fractional anisotropy values was shown for patients (mean ± SD: 0.37 ± 0.02) vs. controls (0.39 ± 0.03) regarding fibers between the left-sided MFG and the putamen (p < 0.05). The same applied for linear anisotropy values in this connection (p < 0.05). CONCLUSIONS Our results suggest an impaired structural connectivity between the left-hemispheric MFG and putamen with a loss of equally aligned fibers in WC patients. This could reflect a structural basis for functional findings interpreted as altered inhibition and plasticity, both within the premotor cortex and the basal ganglia, that at last lead to the clinical symptoms of WC.
Collapse
Affiliation(s)
- Maria Berndt
- Department of Neurology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany.,Department of Neuroradiology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany
| | - Yong Li
- Department of Neurology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany
| | - Gina Gora-Stahlberg
- Department of Neurology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany
| | - Angela Jochim
- Department of Neurology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany
| | - Bernhard Haslinger
- Department of Neurology, Klinikum rechts der Isar, Technische Universität Muenchen, Muenchen, Germany
| |
Collapse
|
16
|
Abstract
Dystonia can be seen in a number of different phenotypes that may arise from different etiologies. The pathophysiological substrate of dystonia is related to three lines of research. The first postulate a loss of inhibition which may account for the excess of movement and for the overflow phenomena. A second abnormality is sensory dysfunction which is related to the mild sensory complaints in patients with focal dystonias and may be responsible for some of the motor dysfunction. Finally, there are strong pieces of evidence from animal and human studies suggesting that alterations of synaptic plasticity characterized by a disruption of homeostatic plasticity, with a prevailing facilitation of synaptic potentiation may play a pivotal role in primary dystonia. These working hypotheses have been generalized in all form of dystonia. On the other hand, several pieces of evidence now suggest that the pathophysiology may be slightly different in the different types of dystonia. Therefore, in the present review, we would like to discuss the neural mechanisms underlying the different forms of dystonia to disentangle the different weight and role of environmental and predisposing factors.
Collapse
Affiliation(s)
- Angelo Quartarone
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy.,IRCCS Centro Neurolesi "Bonino Pulejo", Messina, Italy
| | - Diane Ruge
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Technical University Dortmund, Dortmund, Germany
| |
Collapse
|
17
|
Jhunjhunwala K, Kotikalapudi R, Lenka A, Thennarassu K, Yadav R, Saini J, Pal PK. Abnormalities of Eye-Hand Coordination in Patients with Writer's Cramp: Possible Role of the Cerebellum. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2017; 7:499. [PMID: 29109905 PMCID: PMC5666016 DOI: 10.7916/d8z89qw7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/20/2017] [Indexed: 12/01/2022]
Abstract
Background Writer's cramp (WC) is one of the commonly observed focal dystonias. The pathophysiology of WC has not been fully understood. The role of the cerebellum has been increasingly recognized in the pathogenesis of dystonia. As the cerebellum is crucial for maintaining accurate eye-hand coordination (EHC), its role in the pathogenesis of WC can be investigated by studying the EHC in patients with WC. Methods Fifteen patients with WC (women:men, 3:12) and 15 age- and gender-matched controls performed oculomotor and EHC tasks. A visually guided stimulus (VGS) task was first performed with eye-only condition (EOC) and then with EHC. Results A significant interaction between the groups (controls and patients) and tasks (EOC and EHC) with age as a covariate confirmed that the two groups reacted differently to the tasks in saccadic latency (F(1,27) = 4.8; p = 0.039) and average saccade acceleration (F(1,27) = 10.6; p = 0.003). The curvature index of acceleration of the hand was significantly more in patients compared to controls (patients vs. controls, 2.4±0.4 vs. 1.8±0.2, p = 0.01). While performing the EHC task, there was a significant correlation of the Writer's Cramp Rating Score with the average saccadic speed (-0.61, p = 0.016), peak saccadic deceleration (0.59, p = 0.019) and average saccadic acceleration (-0.63, p = 0.012). Discussion Saccadic acceleration and latency are abnormal while performing EHC tasks in patients with WC. Our study gives further insights into the possible role of the cerebellum in the pathogenesis of WC.
Collapse
Affiliation(s)
- Ketan Jhunjhunwala
- Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India.,Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Raviteja Kotikalapudi
- Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Abhishek Lenka
- Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India.,Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Kandavel Thennarassu
- Department of Biostatistics, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Ravi Yadav
- Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Jitender Saini
- Department of Neuroimaging & Interventional Radiology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, Karnataka, India
| |
Collapse
|
18
|
Langbour N, Michel V, Dilharreguy B, Guehl D, Allard M, Burbaud P. The Cortical Processing of Sensorimotor Sequences is Disrupted in Writer's Cramp. Cereb Cortex 2017; 27:2544-2559. [PMID: 27114174 DOI: 10.1093/cercor/bhw108] [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] [Indexed: 11/13/2022] Open
Abstract
Evidence for pre-existing abnormalities in the sensory and motor systems has been previously reported in writer's cramp (WC). However, the processing of somatosensory information during motor planning has received little attention. We hypothesized that sensorimotor integration processes might be impaired partly due to a disruption in the parieto-premotor network. To test this assumption, we designed 2 nonwriting motor tasks in which subjects had to perform a 4-finger motor sequence either on the basis of sensory stimuli previously memorized (SM task) or freely generated (SG task). Brain activity was measured by combining event-related functional magnetic resonance imaging and coherency electroencephalography in 15 WC patients and 15 normal controls. The bold signal was decreased in patients in both tasks during sensory stimulation but not during movement execution. However, the EEG study showed that coherency was decreased in patients compared with controls, during the delay of the SM task and during the execution of the SG task, on both the whole network and for specific couples of electrodes. Overall, these results demonstrate an endophenotypic impairment in the synchronization of cortical areas within the parieto-premotor network during somatosensory processing and motor planning in WC patients.
Collapse
Affiliation(s)
- N Langbour
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
| | - V Michel
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,Service de Neurophysiologie Clinique, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France
| | - B Dilharreguy
- Université de Bordeaux, INCIA, UMR 5287, F-33400 Talence, France.,CNRS, INCIA, UMR 5287, F-33400 Talence, France
| | - D Guehl
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,Service de Neurophysiologie Clinique, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France
| | - M Allard
- Université de Bordeaux, INCIA, UMR 5287, F-33400 Talence, France.,CNRS, INCIA, UMR 5287, F-33400 Talence, France.,Service de Médecine Nucléaire, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France
| | - P Burbaud
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.,Service de Neurophysiologie Clinique, Centre Hospitalier Universitaire de Bordeaux, 33076 Bordeaux, France
| |
Collapse
|
19
|
Focal task specific dystonia: a review and update. J Neurol 2016; 264:1536-1541. [PMID: 28039522 PMCID: PMC5502053 DOI: 10.1007/s00415-016-8373-z] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 11/15/2022]
Abstract
In this review, we summarize recent advances in understanding the etiology, risk factors and pathophysiology of focal task specific dystonia (FTSD), movement disorders characterized by abnormal motor activation during the performance of specific, repetitive actions. We focus on two common FTSD, musician’s dystonia and writer’s cramp. FTSD may pose a threat to the patient’s livelihood, and improved therapeutic treatments are needed.
Collapse
|
20
|
Furuya S, Hanakawa T. The curse of motor expertise: Use-dependent focal dystonia as a manifestation of maladaptive changes in body representation. Neurosci Res 2015; 104:112-9. [PMID: 26689332 DOI: 10.1016/j.neures.2015.12.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/27/2015] [Accepted: 12/01/2015] [Indexed: 01/20/2023]
Abstract
Focal task-specific dystonia (FTSD) impairs not only motor dexterity, but also somatosensory perception involved in well-trained behavioral tasks. Occupations that carry a risk of developing FTSD include musician, writer, painter, surgeon, and golfer, which are characterized by repetitive and precise motor actions over a prolonged period. Behavioral studies have uncovered various undesirable effects of FTSD on sensorimotor functions, such as a loss of independent movement control, unintended muscular co-activation, awkward limb posture, and impairment of fine discrimination of tactile and proprioceptive sensations. Studies using neuroimaging and noninvasive brain stimulation techniques have related such sensorimotor malfunctions to maladaptive neuroplastic changes in the sensorimotor system, including the primary motor and somatosensory areas, premotor area, cerebellum, and basal ganglia. In this review, we summarize recent empirical findings regarding phenomenological and pathophysiological abnormalities associated with the development of FTSD. We particularly focused on maladaptive alterations of body representations underlying the degradation of fine motor control and somatosensory perception in FTSD patients.
Collapse
Affiliation(s)
- Shinichi Furuya
- Musical Skill and Injury Center (MuSIC), Sophia University, Japan; Integrative Brain Imaging Center (IBIC), National Center of Neurology and Psychiatry, Japan.
| | - Takashi Hanakawa
- Musical Skill and Injury Center (MuSIC), Sophia University, Japan; Integrative Brain Imaging Center (IBIC), National Center of Neurology and Psychiatry, Japan.
| |
Collapse
|
21
|
Gallea C, Balas M, Bertasi E, Valabregue R, García-Lorenzo D, Coynel D, Bonnet C, Grabli D, Pélégrini-Issac M, Doyon J, Benali H, Roze E, Vidailhet M, Lehericy S. Increased cortico-striatal connectivity during motor practice contributes to the consolidation of motor memory in writer's cramp patients. NEUROIMAGE-CLINICAL 2015; 8:180-92. [PMID: 26106542 PMCID: PMC4473821 DOI: 10.1016/j.nicl.2015.04.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 01/19/2023]
Abstract
Sensorimotor representations of movements are created in the sensorimotor network through repeated practice to support successful and effortless performance. Writer's cramp (WC) is a disorder acquired through extensive practice of finger movements, and it is likely associated with the abnormal acquisition of sensorimotor representations. We investigated (i) the activation and connectivity changes in the brain network supporting the acquisition of sensorimotor representations of finger sequences in patients with WC and (ii) the link between these changes and consolidation of motor performance 24 h after the initial practice. Twenty-two patients with WC and 22 age-matched healthy volunteers practiced a complex sequence with the right (pathological) hand during functional MRI recording. Speed and accuracy were measured immediately before and after practice (day 1) and 24 h after practice (day 2). The two groups reached equivalent motor performance on day 1 and day 2. During motor practice, patients with WC had (i) reduced hippocampal activation and hippocampal-striatal functional connectivity; and (ii) overactivation of premotor-striatal areas, whose connectivity correlated with motor performance after consolidation. These results suggest that patients with WC use alternative networks to reach equiperformance in the acquisition of new motor memories.
Collapse
Key Words
- BA, Brodmann area
- CD, consolidation dependent
- CV-RT, coefficient of variation for reaction time
- DT1, dual task 1
- DT2, dual task 2
- FA, fractional anisotropy
- FHD, focal hand dystonia
- Focal dystonia
- HV, healthy volunteers
- Hippocampus
- LD, longitudinal diffusivity
- MRI
- Motor cortex
- PD, practice dependent
- PMd, dorsal premotor cortex
- PMv, ventral premotor cortex
- PPI, psychophysiological interaction
- RD, radial diffusivity
- Striatum
- WC, writer's cramp
Collapse
Affiliation(s)
- C Gallea
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Centre de Neuroimagerie de Recherche, CENIR, Institut du Cerveau et de la Moelle épinière - ICM, Paris, France
| | - M Balas
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Centre de Neuroimagerie de Recherche, CENIR, Institut du Cerveau et de la Moelle épinière - ICM, Paris, France ; Laboratoire d'Imagerie NeuroFonctionnelle, Université Pierre et Marie Curie (UPMC Univ Paris 6), Inserm U678, Paris, France
| | - E Bertasi
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Centre de Neuroimagerie de Recherche, CENIR, Institut du Cerveau et de la Moelle épinière - ICM, Paris, France
| | - R Valabregue
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France
| | - D García-Lorenzo
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France
| | - D Coynel
- Laboratoire d'Imagerie NeuroFonctionnelle, Université Pierre et Marie Curie (UPMC Univ Paris 6), Inserm U678, Paris, France
| | - C Bonnet
- Fédération de Neurologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France ; Centre d'Investigation Clinique, Groupe Hospitalier Pitié-Salpêtrière, Paris, France ; Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - D Grabli
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Fédération de Neurologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France ; Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - M Pélégrini-Issac
- Laboratoire d'Imagerie NeuroFonctionnelle, Université Pierre et Marie Curie (UPMC Univ Paris 6), Inserm U678, Paris, France
| | - J Doyon
- Unité de Neuroimagerie Fonctionnelle et Département de Psychologie, Université de Montréal, Québec, Canada
| | - H Benali
- Laboratoire d'Imagerie NeuroFonctionnelle, Université Pierre et Marie Curie (UPMC Univ Paris 6), Inserm U678, Paris, France
| | - E Roze
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Fédération de Neurologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France ; Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - M Vidailhet
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Fédération de Neurologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France ; Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - S Lehericy
- Université Pierre et Marie Curie (UPMC Univ Paris 6), Institut du Cerveau et de la Moelle épinière - ICM, UMR-S975, Inserm, U975, CNRS, UMR 7225, Paris, France ; Centre de Neuroimagerie de Recherche, CENIR, Institut du Cerveau et de la Moelle épinière - ICM, Paris, France ; Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| |
Collapse
|
22
|
Striatal cholinergic dysfunction as a unifying theme in the pathophysiology of dystonia. Prog Neurobiol 2015; 127-128:91-107. [PMID: 25697043 DOI: 10.1016/j.pneurobio.2015.02.002] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/05/2015] [Accepted: 02/07/2015] [Indexed: 01/06/2023]
Abstract
Dystonia is a movement disorder of both genetic and non-genetic causes, which typically results in twisted posturing due to abnormal muscle contraction. Evidence from dystonia patients and animal models of dystonia indicate a crucial role for the striatal cholinergic system in the pathophysiology of dystonia. In this review, we focus on striatal circuitry and the centrality of the acetylcholine system in the function of the basal ganglia in the control of voluntary movement and ultimately clinical manifestation of movement disorders. We consider the impact of cholinergic interneurons (ChIs) on dopamine-acetylcholine interactions and examine new evidence for impairment of ChIs in dysfunction of the motor systems producing dystonic movements, particularly in animal models. We have observed paradoxical excitation of ChIs in the presence of dopamine D2 receptor agonists and impairment of striatal synaptic plasticity in a mouse model of DYT1 dystonia, which are improved by administration of recently developed M1 receptor antagonists. These findings have been confirmed across multiple animal models of DYT1 dystonia and may represent a common endophenotype by which to investigate dystonia induced by other types of genetic and non-genetic causes and to investigate the potential effectiveness of pharmacotherapeutics and other strategies to improve dystonia.
Collapse
|
23
|
Zeuner KE, Knutzen A, Granert O, Götz J, Wolff S, Jansen O, Dressler D, Hefter H, Hallett M, Deuschl G, van Eimeren T, Witt K. Increased volume and impaired function: the role of the basal ganglia in writer's cramp. Brain Behav 2015; 5:e00301. [PMID: 25642386 PMCID: PMC4309880 DOI: 10.1002/brb3.301] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 11/02/2014] [Accepted: 11/05/2014] [Indexed: 11/09/2022] Open
Abstract
INTRODUCTION The pathophysiology of writer's cramp, a task-specific dystonia, remains unclear. The objective of this study was to investigate the basal ganglia circuit and the cerebellum during a complex motor sequence learning task carried out with the nonaffected hand in writer's cramp patients. METHODS We applied structural and functional imaging in 22 writer's cramp patients and 28 matched controls using 3T MRI. With the asymptomatic left hand all participants learned a complex, sequential, five-element sequence-tapping task as accurately and quickly as possible. Functional imaging was measured during a repeated (15 times), fixed block design with tapping (30 sec) and rest (30 sec). Additionally, gray matter volume of the basal ganglia was analyzed using voxel-based morphometry (VBM). RESULTS While behavior was comparable between groups, after small volume correction the anterior part of the right putamen and the left globus pallidus exhibited reduced blood oxygen level-dependent (BOLD) activity in patients during the sequential finger-tapping task. VBM analysis showed larger gray matter volume bilateral in the posterior part of the putamen and globus pallidus. There were no group differences in the cerebellum. CONCLUSION The results indicate an impairment of anterior basal ganglia loops involved in producing complex sequential movements of the unaffected hand. These findings are in line with previous reports of reduced neuronal activity in the globus pallidus internus. Higher gray matter volume of the putamen and globus pallidus may stem from elevated activity of the direct pathway, which could reflect a compensatory phenomenon or a primary predisposition, that is, endophenotypic trait.
Collapse
Affiliation(s)
| | - Arne Knutzen
- Department of Neurology, Kiel University Kiel, Germany
| | | | - Julia Götz
- Department of Neurology, Kiel University Kiel, Germany
| | - Stephan Wolff
- Department of Neuroradiology, Kiel University Kiel, Germany
| | - Olav Jansen
- Department of Neuroradiology, Kiel University Kiel, Germany
| | - Dirk Dressler
- Movement Disorders Section, Department of Neurology, Hannover Medical School Hannover, Germany
| | - Harald Hefter
- Department of Neurology, University of Düsseldorf Düsseldorf, Germany
| | - Mark Hallett
- Human Motor Control Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health Bethesda, Maryland
| | | | | | - Karsten Witt
- Department of Neurology, Kiel University Kiel, Germany
| |
Collapse
|
24
|
Dresel C, Li Y, Wilzeck V, Castrop F, Zimmer C, Haslinger B. Multiple changes of functional connectivity between sensorimotor areas in focal hand dystonia. J Neurol Neurosurg Psychiatry 2014; 85:1245-52. [PMID: 24706945 DOI: 10.1136/jnnp-2013-307127] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Task-specific focal hand dystonia impairs the control of arm muscles during fine motor skills such as writing (writer's cramp (WC)). Functional imaging found abnormal task-related activation of sensorimotor areas in this disorder, but little is known on their functional connectivity (FC). METHODS Resting-state fMRI and regions of interest (ROI)-voxel cross-correlation analyses were used for systematically analysing the FC between multiple ROIs within the cerebello-basal ganglia-thalamocortical network in 15 patients with right-sided WC and 15 healthy volunteers. RESULTS Patients with WC showed a lower positive FC of several seed ROIs (left lateral premotor cortex, left thalamus, left/right pallidum) to the symptomatic left primary sensorimotor cortex compared with controls. The FC of the left primary motor cortex to prefrontal areas, pre- supplementary motor area and right somatosensory cortex was reduced and correlated with disease severity. Several cerebellar seed ROIs (right dentate nucleus, right crus I and bilateral crus II) revealed a stronger negative FC to primary and secondary sensorimotor areas. CONCLUSIONS An increase of negative cerebello-cortical FC at rest is in line with the hypothesis of a pathogenetic role of the cerebellum in dystonia. The deficit of positive subcortico-cortical FC indicates more generalised changes within the basal ganglia-thalamocortical motor loops beyond primary sensorimotor areas in WC. As patients with WC are asymptomatic during rest, these functional network changes could reflect an underlying abnormality or compensatory neuroplastic changes of network architecture in this disorder.
Collapse
Affiliation(s)
- Christian Dresel
- Department of Neurology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| | - Yong Li
- Department of Neurology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| | - Verena Wilzeck
- Department of Neurology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| | - Florian Castrop
- Department of Neurology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| | - Claus Zimmer
- Department of Neuroradiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| | - Bernhard Haslinger
- Department of Neurology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
| |
Collapse
|
25
|
Perruchoud D, Murray MM, Lefebvre J, Ionta S. Focal dystonia and the Sensory-Motor Integrative Loop for Enacting (SMILE). Front Hum Neurosci 2014; 8:458. [PMID: 24999327 PMCID: PMC4064702 DOI: 10.3389/fnhum.2014.00458] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 06/04/2014] [Indexed: 12/12/2022] Open
Abstract
Performing accurate movements requires preparation, execution, and monitoring mechanisms. The first two are coded by the motor system, the latter by the sensory system. To provide an adaptive neural basis to overt behaviors, motor and sensory information has to be properly integrated in a reciprocal feedback loop. Abnormalities in this sensory-motor loop are involved in movement disorders such as focal dystonia, a hyperkinetic alteration affecting only a specific body part and characterized by sensory and motor deficits in the absence of basic motor impairments. Despite the fundamental impact of sensory-motor integration mechanisms on daily life, the general principles of healthy and pathological anatomic–functional organization of sensory-motor integration remain to be clarified. Based on the available data from experimental psychology, neurophysiology, and neuroimaging, we propose a bio-computational model of sensory-motor integration: the Sensory-Motor Integrative Loop for Enacting (SMILE). Aiming at direct therapeutic implementations and with the final target of implementing novel intervention protocols for motor rehabilitation, our main goal is to provide the information necessary for further validating the SMILE model. By translating neuroscientific hypotheses into empirical investigations and clinically relevant questions, the prediction based on the SMILE model can be further extended to other pathological conditions characterized by impaired sensory-motor integration.
Collapse
Affiliation(s)
- David Perruchoud
- Laboratory for Investigative Neurophysiology, Department of Radiology and Department of Clinical Neurosciences, University Hospital Center and University of Lausanne Lausanne, Switzerland
| | - Micah M Murray
- Laboratory for Investigative Neurophysiology, Department of Radiology and Department of Clinical Neurosciences, University Hospital Center and University of Lausanne Lausanne, Switzerland ; The Electroencephalography Brain Mapping Core, Center for Biomedical Imaging Lausanne, Switzerland
| | - Jeremie Lefebvre
- Laboratory for Investigative Neurophysiology, Department of Radiology and Department of Clinical Neurosciences, University Hospital Center and University of Lausanne Lausanne, Switzerland
| | - Silvio Ionta
- Laboratory for Investigative Neurophysiology, Department of Radiology and Department of Clinical Neurosciences, University Hospital Center and University of Lausanne Lausanne, Switzerland
| |
Collapse
|
26
|
Lehéricy S, Tijssen MAJ, Vidailhet M, Kaji R, Meunier S. The anatomical basis of dystonia: current view using neuroimaging. Mov Disord 2014; 28:944-57. [PMID: 23893451 DOI: 10.1002/mds.25527] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 04/06/2013] [Accepted: 05/02/2013] [Indexed: 12/15/2022] Open
Abstract
This review will consider the knowledge that neuroimaging studies have provided to the understanding of the anatomy of dystonia. Major advances have occurred in the use of neuroimaging for dystonia in the past 2 decades. At present, the most developed imaging approaches include whole-brain or region-specific studies of structural or diffusion changes, functional imaging using fMRI or positron emission tomography (PET), and metabolic imaging using fluorodeoxyglucose PET. These techniques have provided evidence that regions other than the basal ganglia are involved in dystonia. In particular, there is increasing evidence that primary dystonia can be viewed as a circuit disorder, involving the basal ganglia-thalamo-cortical and cerebello-thalamo-cortical pathways. This suggests that a better understanding of the dysfunction in each region in the network and their interactions are important topics to address. Current views of interpretation of imaging data as cause or consequence of dystonia, and the postmortem correlates of imaging data are presented. The application of imaging as a tool to monitor therapy and its use as an outcome measure will be discussed. © 2013 Movement Disorder Society.
Collapse
Affiliation(s)
- Stéphane Lehéricy
- Institut du Cerveau et de la Moelle (ICM) epiniere, Centre de NeuroImagerie de Recherche (CENIR), Paris, France.
| | | | | | | | | |
Collapse
|
27
|
Abstract
This chapter focuses on neurodevelopmental diseases that are tightly linked to abnormal function of the striatum and connected structures. We begin with an overview of three representative diseases in which striatal dysfunction plays a key role--Tourette syndrome and obsessive-compulsive disorder, Rett's syndrome, and primary dystonia. These diseases highlight distinct etiologies that disrupt striatal integrity and function during development, and showcase the varied clinical manifestations of striatal dysfunction. We then review striatal organization and function, including evidence for striatal roles in online motor control/action selection, reinforcement learning, habit formation, and action sequencing. A key barrier to progress has been the relative lack of animal models of these diseases, though recently there has been considerable progress. We review these efforts, including their relative merits providing insight into disease pathogenesis, disease symptomatology, and basal ganglia function.
Collapse
|
28
|
Altered striatal and pallidal connectivity in cervical dystonia. Brain Struct Funct 2013; 220:513-23. [PMID: 24259114 DOI: 10.1007/s00429-013-0671-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/31/2013] [Indexed: 12/30/2022]
Abstract
Cervical dystonia is a neurological movement disorder characterized by involuntary, abnormal movements of the head and neck. Injecting the overactive muscles with botulinum toxin is the gold standard treatment, supported by good evidence (Delnooz and van de Warrenburg in Ther Adv Neurol Disord 5:221-240, 2012). Current views on its pathophysiology support a role for the basal ganglia, although there are probably more widespread abnormalities in brain networks in which the basal ganglia are important nodes. Their precise role in cervical dystonia is unknown. We sought to address this issue by examining alterations in the functional connectivity of the basal ganglia. Using resting-state functional MRI and functional parcellations, we investigated functional connectivity in cervical dystonia patients and age- and gender-matched healthy controls. We mapped connectivity voxel-wise across the striatum and the globus pallidus for a set of brain masks, defined from well-known resting-state networks. Scans were repeated before and after botulinum toxin injections to see whether connectivity abnormalities were perhaps restored. We found that in cervical dystonia (1) the right mid-dorsal putamen and right external globus pallidus have reduced connectivity with a network comprising left fronto-parietal regions; and (2) the bilateral anterior putamen shows a trend towards enhanced connectivity with a network comprising sensorimotor areas. We observed that botulinum toxin treatment induces reorganization between a network comprising mainly (pre)frontal areas and (1) the right mid-ventral striatum and (2) the right external globus pallidus. Cervical dystonia patients have altered functional connectivity between the basal ganglia and some cortical regions that are part of specific brain networks that in part are influenced by botulinum toxin treatment. These connectivity abnormalities may be primary as well as secondary, perhaps compensatory, phenomena.
Collapse
|
29
|
Jankowski J, Paus S, Scheef L, Bewersdorff M, Schild HH, Klockgether T, Boecker H. Abnormal movement preparation in task-specific focal hand dystonia. PLoS One 2013; 8:e78234. [PMID: 24167610 PMCID: PMC3805688 DOI: 10.1371/journal.pone.0078234] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 09/10/2013] [Indexed: 11/25/2022] Open
Abstract
Electrophysiological and behavioral studies in primary dystonia suggest abnormalities during movement preparation, but this crucial phase preceding movement onset has not yet been studied specifically with functional magnetic resonance imaging (fMRI). To identify abnormalities in brain activation during movement preparation, we used event-related fMRI to analyze behaviorally unimpaired sequential finger movements in 18 patients with task-specific focal hand dystonia (FHD) and 18 healthy subjects. Patients and controls executed self-initiated or externally cued prelearnt four-digit sequential movements using either right or left hands. In FHD patients, motor performance of the sequential finger task was not associated with task-related dystonic posturing and their activation levels during motor execution were highly comparable with controls. On the other hand reduced activation was observed during movement preparation in the FHD patients in left premotor cortex / precentral gyrus for all conditions, and for self-initiation additionally in supplementary motor area, left mid-insula and anterior putamen, independent of effector side. Findings argue for abnormalities of early stages of motor control in FHD, manifesting during movement preparation. Since deficits map to regions involved in the coding of motor programs, we propose that task-specific dystonia is characterized by abnormalities during recruitment of motor programs: these do not manifest at the behavioral level during simple automated movements, however, errors in motor programs of complex movements established by extensive practice (a core feature of FHD), trigger the inappropriate movement patterns observed in task-specific dystonia.
Collapse
Affiliation(s)
- Jakob Jankowski
- FE Funktionelle Neurobildgebung, Radiologische Universitätsklinik, Universität Bonn, Bonn, Germany
| | - Sebastian Paus
- Neurologische Universitätsklinik, Universität Bonn, Bonn, Germany
| | - Lukas Scheef
- FE Funktionelle Neurobildgebung, Radiologische Universitätsklinik, Universität Bonn, Bonn, Germany
| | - Malte Bewersdorff
- FE Funktionelle Neurobildgebung, Radiologische Universitätsklinik, Universität Bonn, Bonn, Germany
| | - Hans H. Schild
- Radiologische Universitätsklinik, Universität Bonn, Bonn, Germany
| | - Thomas Klockgether
- Neurologische Universitätsklinik, Universität Bonn, Bonn, Germany
- German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Henning Boecker
- FE Funktionelle Neurobildgebung, Radiologische Universitätsklinik, Universität Bonn, Bonn, Germany
- * E-mail:
| |
Collapse
|
30
|
Hinkley LBN, Sekihara K, Owen JP, Westlake KP, Byl NN, Nagarajan SS. Complex-value coherence mapping reveals novel abnormal resting-state functional connectivity networks in task-specific focal hand dystonia. Front Neurol 2013; 4:149. [PMID: 24133480 PMCID: PMC3794296 DOI: 10.3389/fneur.2013.00149] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 09/18/2013] [Indexed: 01/14/2023] Open
Abstract
Resting-state imaging designs are powerful in modeling functional networks in movement disorders because they eliminate task performance related confounds. However, the most common metric for quantifying functional connectivity, i.e., bivariate magnitude coherence (Coh), can sometimes be contaminated by spurious correlations in blood-oxygen level dependent (BOLD) signal due to smoothing and seed blur, thereby limiting the identification of true interactions between neighboring neural populations. Here, we apply a novel functional connectivity metric., i.e., imaginary coherence (ICoh), to BOLD fMRI data in healthy individuals and patients with task-specific focal hand dystonia (tspFHD), in addition to the traditional magnitude Coh metric. We reconstructed resting-state sensorimotor, basal ganglia, and default-mode networks using both Coh and ICoh. We demonstrate that indeed the ICoh metric eliminates spatial blur around seed placement and reflects slightly different networks from Coh. We then identified significant reductions in resting-state connectivity within both the sensorimotor and basal ganglia networks in patients with tspFHD, primarily in the hemisphere contralateral to the affected hand. Collectively, these findings direct our attention to the fact that multiple networks are decoupled in tspFHD that can be unraveled by different functional connectivity metrics, and that this aberrant communication contributes to clinical deficits in the disorder.
Collapse
Affiliation(s)
- Leighton B. N. Hinkley
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Kensuke Sekihara
- Department of Systems Design and Engineering, Tokyo Metropolitan University, Tokyo, Japan
| | - Julia P. Owen
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Kelly P. Westlake
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Nancy N. Byl
- Department of Physical Therapy and Rehabilitation Science, University of California San Francisco, San Francisco, CA, USA
| | - Srikantan S. Nagarajan
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| |
Collapse
|
31
|
Focal task-specific lower extremity dystonia associated with intense repetitive exercise: a case series. Parkinsonism Relat Disord 2013; 19:1033-8. [PMID: 23932354 DOI: 10.1016/j.parkreldis.2013.07.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 06/28/2013] [Accepted: 07/15/2013] [Indexed: 11/22/2022]
Abstract
BACKGROUND Focal task-specific dystonia of the lower extremity associated with intense repetitive exercise has recently been recognized. The clinical course, treatment response and prognosis remain poorly understood. METHODS Individuals with lower extremity task-specific dystonia evaluated at UCSF's Movement Disorders Center (2004-2012) were eligible for this descriptive case study series if he/she had a history of strenuous and prolonged exercise involving the lower extremity and had no abnormal neurological or medical conditions to explain the involuntary movements. Data was gathered from the medical history and a self-report questionnaire. The findings were compared to 14 cases previously reported in the literature. RESULTS Seven cases (4M/3F) were identified with a diverse set of exercise triggers (cycling, hiking, long-distance running, drumming). The mean age of symptom onset was 53.7 ± 6.1 years. The median symptom duration prior to diagnosis was 4 (9.5) years. Several patients underwent unnecessary procedures prior to being appropriately diagnosed. Over a median of 2 (3.5) years, signs and symptoms progressed to impair walking. Seven patients had improvement in gait with treatment (e.g. botulinum toxin injections, benzodiazepines, physical therapy, bracing, body weight supported gait training and/or functional electrical stimulation of the peroneal nerve) and six returned to a reduced intensity exercise routine. CONCLUSIONS Isolated lower extremity dystonia associated with strenuous, repetitive exercise is relatively uncommon, but disabling and challenging to treat. The pathophysiology may be similar to task-specific focal dystonias of the upper limb. Prompt recognition of leg dystonia associated with extreme exercise could minimize unnecessary testing and procedures, and facilitate earlier treatment.
Collapse
|
32
|
Sivadasan A, Sanjay M, Alexander M, Devasahayam SR, Srinivasa BK. Utility of multi-channel surface electromyography in assessment of focal hand dystonia. Muscle Nerve 2013; 48:415-22. [PMID: 23861190 DOI: 10.1002/mus.23762] [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] [Accepted: 12/13/2012] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Surface electromyography (SEMG) allows objective assessment and guides selection of appropriate treatment in focal hand dystonia (FHD). METHODS Sixteen-channel SEMG obtained during different phases of a writing task was used to study timing, activation patterns, and spread of muscle contractions in FHD compared with normal controls. Customized software was developed to acquire and analyze EMG signals. RESULTS SEMG of FHD subjects (20) showed "early onset" during motor imagery, rapid proximal muscle recruitment, agonist-antagonist co-contraction involving proximal muscle groups, "delayed offset" after stopping writing, higher rectified mean amplitudes, and mirror activity in contralateral limb compared with controls (16). Muscle activation latencies were heterogenous in FHD. CONCLUSIONS Anticipation, delayed relaxation, and mirror EMG activation were noted in FHD. A clear pattern of muscle activation cannot be ascertained. Multi-channel SEMG can aid in objective assessment of temporal-spatial distribution of activity and can refine targeted therapies like chemodenervation and biofeedback.
Collapse
Affiliation(s)
- Ajith Sivadasan
- Department of Neurological Sciences, Christian Medical College, Vellore, India, 632004
| | | | | | | | | |
Collapse
|
33
|
Delnooz CCS, Pasman JW, Beckmann CF, van de Warrenburg BPC. Task-free functional MRI in cervical dystonia reveals multi-network changes that partially normalize with botulinum toxin. PLoS One 2013; 8:e62877. [PMID: 23650536 PMCID: PMC3641096 DOI: 10.1371/journal.pone.0062877] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 03/27/2013] [Indexed: 11/18/2022] Open
Abstract
Cervical dystonia is characterized by involuntary, abnormal movements and postures of the head and neck. Current views on its pathophysiology, such as faulty sensorimotor integration and impaired motor planning, are largely based on studies of focal hand dystonia. Using resting state fMRI, we explored whether cervical dystonia patients have altered functional brain connectivity compared to healthy controls, by investigating 10 resting state networks. Scans were repeated immediately before and some weeks after botulinum toxin injections to see whether connectivity abnormalities were restored. We here show that cervical dystonia patients have reduced connectivity in selected regions of the prefrontal cortex, premotor cortex and superior parietal lobule within a distributed network that comprises the premotor cortex, supplementary motor area, primary sensorimotor cortex, and secondary somatosensory cortex (sensorimotor network). With regard to a network originating from the occipital cortex (primary visual network), selected regions in the prefrontal and premotor cortex, superior parietal lobule, and middle temporal gyrus areas have reduced connectivity. In selected regions of the prefrontal, premotor, primary motor and early visual cortex increased connectivity was found within a network that comprises the prefrontal cortex including the anterior cingulate cortex and parietal cortex (executive control network). Botulinum toxin treatment resulted in a partial restoration of connectivity abnormalities in the sensorimotor and primary visual network. These findings demonstrate the involvement of multiple neural networks in cervical dystonia. The reduced connectivity within the sensorimotor and primary visual networks may provide the neural substrate to expect defective motor planning and disturbed spatial cognition. Increased connectivity within the executive control network suggests excessive attentional control and while this may be a primary trait, perhaps contributing to abnormal motor control, this may alternatively serve a compensatory function in order to reduce the consequences of the motor planning defect inflicted by the other network abnormalities.
Collapse
Affiliation(s)
- Cathérine C S Delnooz
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands
| | | | | | | |
Collapse
|
34
|
Deik AF, O'Riordan S, Luciano MS, Shanker VL, Raymond D, Bressman SB, Saunders-Pullman R. Spatial Discrimination Threshold Abnormalities are not Detected in a Pilot Study of DYT6 Dystonia Mutation Carriers. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2013; 2. [PMID: 23439738 PMCID: PMC3570067 DOI: 10.7916/d8pr7tpc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 05/26/2012] [Indexed: 12/01/2022]
Abstract
Background Spatial discrimination thresholds (SDTs) assess somatosensory integration, and provide a window into better understanding the pathophysiology of dystonia. They are abnormal in some focal dystonias, but normal in DYT1 dystonia. It is unknown whether SDTs are altered in DYT6 gene mutation carriers (C). Methods SDTs were assessed in 17 DYT6 C (including eight manifesting carriers), 15 DYT1 C (including seven manifesting carriers) and 34 controls, using a standardized grating orientation task. Subjects were asked to recognize the orientation of Johnson–Van Boven–Philips (JVP) dome gratings on either index fingertip until 40% or more answers were incorrect. SDTs between indexes were calculated and averaged, with a final SDT assigned to each subject, and tertiles for control SDTs were constructed. Results SDTs of DYT6 C or DYT1 C were comparable to those of controls, and not more likely to be in the worst tertile (p = 0.8 for DYT6 C vs. controls and p = 1.0 for DYT1 C vs. controls). This was independent of gene expression. Discussion DYT6 carriers do not have impaired SDTs with the JVP dome paradigm. The normal SDT pattern thus suggests shared sensory physiologic patterns with DYT1 dystonia.
Collapse
Affiliation(s)
- Andres F Deik
- Department of Neurology, Beth Israel Medical Center, New York, New York, United States of America
| | | | | | | | | | | | | |
Collapse
|
35
|
Hinkley LBN, Dolberg R, Honma S, Findlay A, Byl NN, Nagarajan SS. Aberrant Oscillatory Activity during Simple Movement in Task-Specific Focal Hand Dystonia. Front Neurol 2012; 3:165. [PMID: 23226140 PMCID: PMC3508423 DOI: 10.3389/fneur.2012.00165] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 10/31/2012] [Indexed: 11/29/2022] Open
Abstract
In task-specific focal hand dystonia (tspFHD), the temporal dynamics of cortical activity in the motor system and how these processes are related to impairments in sensory and motor function are poorly understood. Here, we use time-frequency reconstructions of magnetoencephalographic (MEG) data to elaborate the temporal and spatial characteristics of cortical activity during movement. A self-paced finger tapping task during MEG recording was performed by 11 patients with tspFHD and 11 matched healthy controls. In both groups robust changes in beta (12-30 Hz) and high gamma (65-90 Hz) oscillatory activity were identified over sensory and motor cortices during button press. A significant decrease [p < 0.05, 1% False Discovery Rate (FDR) corrected] in high gamma power during movements of the affected hand was identified over ipsilateral sensorimotor cortex in the period prior to (-575 ms) and following (725 ms) button press. Furthermore, an increase (p < 0.05, 1% FDR corrected) in beta power suppression following movement of the affected hand was identified over visual cortex in patients with tspFHD. For movements of the unaffected hand, a significant (p < 0.05, 1% FDR corrected) increase in beta power suppression was identified over secondary somatosensory cortex (S2) in the period following button press in patients with tspFHD. Oscillatory activity within in the tspFHD group was however not correlated with clinical measures. Understanding these aberrant oscillatory dynamics can provide the groundwork for interventions that focus on modulating the timing of this activity.
Collapse
Affiliation(s)
- Leighton B. N. Hinkley
- Department of Radiology and Biomedical Imaging, University of CaliforniaSan Francisco, CA, USA
| | - Rebecca Dolberg
- Department of Physical Therapy and Rehabilitation Science, University of CaliforniaSan Francisco, CA, USA
| | - Susanne Honma
- Department of Radiology and Biomedical Imaging, University of CaliforniaSan Francisco, CA, USA
| | - Anne Findlay
- Department of Radiology and Biomedical Imaging, University of CaliforniaSan Francisco, CA, USA
| | - Nancy N. Byl
- Department of Physical Therapy and Rehabilitation Science, University of CaliforniaSan Francisco, CA, USA
| | - Srikantan S. Nagarajan
- Department of Radiology and Biomedical Imaging, University of CaliforniaSan Francisco, CA, USA
| |
Collapse
|
36
|
de Vries PM, de Jong BM, Bohning DE, Hinson VK, George MS, Leenders KL. Reduced parietal activation in cervical dystonia after parietal TMS interleaved with fMRI. Clin Neurol Neurosurg 2012; 114:914-21. [DOI: 10.1016/j.clineuro.2012.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 02/04/2012] [Accepted: 02/06/2012] [Indexed: 10/28/2022]
|
37
|
Meunier S, Russmann H, Shamim E, Lamy JC, Hallett M. Plasticity of cortical inhibition in dystonia is impaired after motor learning and paired-associative stimulation. Eur J Neurosci 2012; 35:975-86. [PMID: 22429246 DOI: 10.1111/j.1460-9568.2012.08034.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Artificial induction of plasticity by paired associative stimulation (PAS) in healthy volunteers (HV) demonstrates Hebbian-like plasticity in selected inhibitory networks as well as excitatory networks. In a group of 17 patients with focal hand dystonia and a group of 19 HV, we evaluated how PAS and the learning of a simple motor task influence the circuits supporting long-interval intracortical inhibition (LICI, reflecting activity of GABA(B) interneurons) and long-latency afferent inhibition (LAI, reflecting activity of somatosensory inputs to the motor cortex). In HV, PAS and motor learning induced long-term potentiation (LTP)-like plasticity of excitatory networks and a lasting decrease of LAI and LICI in the motor representation of the targeted or trained muscle. The better the motor performance, the larger was the decrease of LAI. Although motor performance in the patient group was similar to that of the control group, LAI did not decrease during the motor learning as it did in the control group. In contrast, LICI was normally modulated. In patients the results after PAS did not match those obtained after motor learning: LAI was paradoxically increased and LICI did not exhibit any change. In the normal situation, decreased excitability in inhibitory circuits after induction of LTP-like plasticity may help to shape the cortical maps according to the new sensorimotor task. In patients, the abnormal or absent modulation of afferent and intracortical long-interval inhibition might indicate maladaptive plasticity that possibly contributes to the difficulty that they have to learn a new sensorimotor task.
Collapse
Affiliation(s)
- Sabine Meunier
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health, Bethesda, MD, USA
| | | | | | | | | |
Collapse
|
38
|
Zheng Z, Pan P, Wang W, Shang H. Neural network of primary focal dystonia by an anatomic likelihood estimation meta-analysis of gray matter abnormalities. J Neurol Sci 2012; 316:51-5. [PMID: 22349356 DOI: 10.1016/j.jns.2012.01.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 01/21/2012] [Accepted: 01/31/2012] [Indexed: 02/05/2023]
Abstract
BACKGROUND Recent voxel-based morphometry (VBM) studies have found gray matter (GM) abnormalities in primary focal dystonia (PFD) and yielded inconsistent results. AIM Our aim is to investigate consistent GM changes in PFD and to identify whether different subtypes of PFD share a common pathophysiological basis revealed by structural abnormalities. METHODS A systematic search of VBM studies of patients with PFD and healthy control (HC) subjects published in PubMed, Embase, and Medline databases from January 1998 to April 2011 was conducted. We performed a voxel-wise meta-analysis of VBM studies comparing PFD to HC using the anatomic likelihood estimation (ALE) method. RESULTS A total of 9 articles, which reported 11 PFD-HC comparisons including 199 PFD patients and 247 HC subjects, met the inclusion criteria. GM volume (GMV) was found to be greater in the caudate, postcentral cortex (BA2, 3, 40) and primary motor cortex, and smaller in the thalamus and putamen. CONCLUSION Our findings provide evidence for structural abnormalities within the sensorimotor network involved in the pathophysiology of PFD. However, our work could not distinguish whether the brain structural changes are primary or secondary to PFD.
Collapse
Affiliation(s)
- ZhenZhen Zheng
- Department of Neurology, West China Hospital, Sichuan University, 610041, Chengdu, Sichuan, China
| | | | | | | |
Collapse
|
39
|
Thompson VB, Jinnah HA, Hess EJ. Convergent mechanisms in etiologically-diverse dystonias. Expert Opin Ther Targets 2011; 15:1387-403. [PMID: 22136648 DOI: 10.1517/14728222.2011.641533] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Dystonia is a neurological disorder associated with twisting motions and abnormal postures, which compromise normal movements and can be both painful and debilitating. It can affect a single body part (focal), several contiguous regions (segmental), or the entire body (generalized), and can arise as a result of numerous causes, both genetic and acquired. Despite the diversity of causes and manifestations, shared clinical features suggest that common mechanisms of pathogenesis may underlie many dystonias. AREAS COVERED Shared themes in etiologically-diverse dystonias exist at several biological levels. At the cellular level, abnormalities in the dopaminergic system, mitochondrial function and calcium regulation are often present. At the anatomical level, the basal ganglia and the cerebellum are frequently implicated. Global CNS dysfunction, specifically aberrant neuronal plasticity, inhibition and sensorimotor integration, are also observed in a number of dystonias. Using clinical data and data from animal models, this article seeks to highlight shared pathways that may be critical in understanding mechanisms and identifying novel therapeutic strategies in dystonia. EXPERT OPINION Identifying shared features of pathogenesis can provide insight into the biological processes that underlie etiologically diverse dystonias, and can suggest novel targets for therapeutic intervention that may be effective in a broad group of affected individuals.
Collapse
Affiliation(s)
- Valerie B Thompson
- Emory University School of Medicine, Department of Pharmacology, Woodruff Memorial Research Building, Suite 6000, 101 Woodruff Circle, Atlanta, GA 30322, USA
| | | | | |
Collapse
|
40
|
Jin SH, Lin P, Auh S, Hallett M. Abnormal functional connectivity in focal hand dystonia: mutual information analysis in EEG. Mov Disord 2011; 26:1274-81. [PMID: 21506166 PMCID: PMC3119738 DOI: 10.1002/mds.23675] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 12/16/2010] [Accepted: 01/13/2011] [Indexed: 11/06/2022] Open
Abstract
The aim of the present study was to investigate functional connectivity in focal hand dystonia patients to understand the pathophysiology underlying their abnormality in movement. We recorded EEGs from 58 electrodes in 15 focal hand dystonia patients and 15 healthy volunteers during rest and a simple finger-tapping task that did not induce any dystonic symptoms. We investigated mutual information, which provides a quantitative measure of linear and nonlinear coupling, in the alpha, beta, and gamma bands. Mean mutual information of all 58 channels and mean of the channels of interest representative of regional functional connectivity over sensorimotor areas (C3, CP3, C4, CP4, FCz, and Cz) were evaluated. For both groups, we found enhanced mutual information during the task compared with the rest condition, specifically in the beta and gamma bands for mean mutual information of all channels, and in all bands for mean mutual information of channels of interest. Comparing the focal hand dystonia patients with the healthy volunteers for both rest and task, there was reduced mutual information in the beta band for both mean mutual information of all channels and mean mutual information of channels of interest. Regarding the properties of the connectivity in the beta band, we found that the majority of the mutual information differences were from linear connectivity. The abnormal beta-band functional connectivity in focal hand dystonia patients suggests deficient brain connectivity.
Collapse
Affiliation(s)
- Seung-Hyun Jin
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Peter Lin
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Sungyoung Auh
- Clinical Neurosciences Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
41
|
Zoons E, Booij J, Nederveen AJ, Dijk JM, Tijssen MAJ. Structural, functional and molecular imaging of the brain in primary focal dystonia--a review. Neuroimage 2011; 56:1011-20. [PMID: 21349339 DOI: 10.1016/j.neuroimage.2011.02.045] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 02/11/2011] [Accepted: 02/15/2011] [Indexed: 12/31/2022] Open
Abstract
Primary focal dystonias form a group of neurological disorders characterized by involuntary, sustained muscle contractions causing twisting movements and abnormal postures. The estimated incidence is 12-25 per 100,000. The pathophysiology is largely unclear but genetic and environmental influences are suspected. Over the last decade neuroimaging techniques have been applied in patients with focal dystonia. Using structural, functional and molecular imaging techniques, abnormalities have been detected mainly in the sensorimotor cortex, basal ganglia and cerebellum. The shared anatomical localisations in different forms of focal dystonia support the hypothesis of a common causative mechanism. The primary defect in focal dystonia is hypothesised in the motor circuit connecting the cortex, basal ganglia, and cerebellum. Imaging techniques have clearly enhanced current knowledge on the pathophysiology of primary focal dystonia and will continue to do so in the future.
Collapse
Affiliation(s)
- E Zoons
- Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands
| | | | | | | | | |
Collapse
|
42
|
Neychev VK, Gross RE, Lehéricy S, Hess EJ, Jinnah HA. The functional neuroanatomy of dystonia. Neurobiol Dis 2011; 42:185-201. [PMID: 21303695 DOI: 10.1016/j.nbd.2011.01.026] [Citation(s) in RCA: 320] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 01/08/2011] [Accepted: 01/28/2011] [Indexed: 10/18/2022] Open
Abstract
Dystonia is a neurological disorder characterized by involuntary twisting movements and postures. There are many different clinical manifestations, and many different causes. The neuroanatomical substrates for dystonia are only partly understood. Although the traditional view localizes dystonia to basal ganglia circuits, there is increasing recognition that this view is inadequate for accommodating a substantial portion of available clinical and experimental evidence. A model in which several brain regions play a role in a network better accommodates the evidence. This network model accommodates neuropathological and neuroimaging evidence that dystonia may be associated with abnormalities in multiple different brain regions. It also accommodates animal studies showing that dystonic movements arise with manipulations of different brain regions. It is consistent with neurophysiological evidence suggesting defects in neural inhibitory processes, sensorimotor integration, and maladaptive plasticity. Finally, it may explain neurosurgical experience showing that targeting the basal ganglia is effective only for certain subpopulations of dystonia. Most importantly, the network model provides many new and testable hypotheses with direct relevance for new treatment strategies that go beyond the basal ganglia. This article is part of a Special Issue entitled "Advances in dystonia".
Collapse
|
43
|
Abstract
BACKGROUND Impaired cortical inhibiton and maladaptive cortical plasticity are functional hallmarks of sporadic focal dystonias. Whether or not these mechanisms translate to generalized dystonias and whether these features reflect state or trait characteristics are topics of research in hereditary dystonias. METHODS We present a series of studies using a multitracer approach with positron emission tomography (PET) and diffusion tensor MRI (DTI) in the DYT1 and the DYT6 genotype. RESULTS In these hereditary dystonias functional and microstructural abnormalities were found in cortico-striatal-pallido-thalamocortical (CSPTC) and cerebellar-thalamo-cortical circuits. Genotype-specific abnormalities were localized to the basal ganglia, SMA and cerebellum. Functional changes, as potential correlates of maladaptive sensorimotor plasticity were found throughout the sensorimotor system and were more pronounced in affected mutation carriers than in their non-manifesting counterparts. In both genotypes, striatal metabolic abnormalities were paralleled by genotype-specific reductions in D(2) receptor availability. However, these reductions failed to show a clear association with clinical or functional markers of the disease. By contrast, microstructural changes of cerebellar pathways clearly related to penetrance and may thus represent the main intrinsic abnormality underlying cortical downstream effects, such as increased sensorimotor responsivity. CONCLUSIONS These studies are consistent with the view of primary torsion dystonia as a neurodevelopmental circuit disorder involving CSPTC and related cerebellar pathways.
Collapse
Affiliation(s)
- M Carbon
- Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore - Long Island Jewish Health System, Manhasset, NY 11030, USA.
| | | | | |
Collapse
|
44
|
Spraker MB, Prodoehl J, Corcos DM, Comella CL, Vaillancourt DE. Basal ganglia hypoactivity during grip force in drug naïve Parkinson's disease. Hum Brain Mapp 2010; 31:1928-41. [PMID: 20225221 DOI: 10.1002/hbm.20987] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The basal ganglia (BG) are impaired in Parkinson's disease (PD), but it remains unclear which nuclei are impaired during the performance of motor tasks in early-stage PD. Therefore, this study was conducted to determine which nuclei function abnormally, and whether cortical structures are also affected by early-stage PD. The study also determined if cerebellar hyperactivity is found early in the course of PD. Blood oxygenation level dependent activation was compared between 14 early-stage drug-naïve PD patients and 14 controls performing two precision grip force tasks using functional magnetic resonance imaging at 3 T. The grip tasks used in this study were chosen because both tasks are known to provide robust activation in BG nuclei, and the two tasks were similar except that the 2-s task required more switching between contraction and relaxation than the 4-s task. The 4-s task revealed that PD patients were hypoactive relative to controls only in putamen and external globus pallidus, and thalamus. In the 2-s task, PD patients were hypoactive throughout all BG nuclei, thalamus, M1, and supplementary motor area. There were no differences in cerebellar activation between groups during either task. Regions of interest analysis revealed that the hypoactivity observed in PD patients during the 2-s task became more pronounced over time as patients performed the task. This suggests that a motor task that requires switching can accentuate abnormal activity throughout all BG nuclei of early-stage, drug-naive PD, and that the abnormal activity becomes more pronounced with repeated task performance in these patients.
Collapse
Affiliation(s)
- Matthew B Spraker
- Department of Bioengineering, University of Illinois, Chicago, Illinois, USA
| | | | | | | | | |
Collapse
|
45
|
Carbon M, Argyelan M, Habeck C, Ghilardi MF, Fitzpatrick T, Dhawan V, Pourfar M, Bressman SB, Eidelberg D. Increased sensorimotor network activity in DYT1 dystonia: a functional imaging study. ACTA ACUST UNITED AC 2010; 133:690-700. [PMID: 20207699 DOI: 10.1093/brain/awq017] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Neurophysiological studies have provided evidence of primary motor cortex hyperexcitability in primary dystonia, but several functional imaging studies suggest otherwise. To address this issue, we measured sensorimotor activation at both the regional and network levels in carriers of the DYT1 dystonia mutation and in control subjects. We used (15)Oxygen-labelled water and positron emission tomography to scan nine manifesting DYT1 carriers, 10 non-manifesting DYT1 carriers and 12 age-matched controls while they performed a kinematically controlled motor task; they were also scanned in a non-motor audio-visual control condition. Within- and between-group contrasts were analysed with statistical parametric mapping. For network analysis, we first identified a normal motor-related activation pattern in a set of 39 motor and audio-visual scans acquired in an independent cohort of 18 healthy volunteer subjects. The expression of this pattern was prospectively quantified in the motor and control scans acquired in each of the gene carriers and controls. Network values for the three groups were compared with ANOVA and post hoc contrasts. Voxel-wise comparison of DYT1 carriers and controls revealed abnormally increased motor activation responses in the former group (P < 0.05, corrected; statistical parametric mapping), localized to the sensorimotor cortex, dorsal premotor cortex, supplementary motor area and the inferior parietal cortex. Network analysis of the normative derivation cohort revealed a significant normal motor-related activation pattern topography (P < 0.0001) characterized by covarying neural activity in the sensorimotor cortex, dorsal premotor cortex, supplementary motor area and cerebellum. In the study cohort, normal motor-related activation pattern expression measured during movement was abnormally elevated in the manifesting gene carriers (P < 0.001) but not in their non-manifesting counterparts. In contrast, in the non-motor control condition, abnormal increases in network activity were present in both groups of gene carriers (P < 0.001). In this condition, normal motor-related activation pattern expression in non-manifesting carriers was greater than in controls, but lower than in affected carriers. In the latter group, measures of normal motor-related activation pattern expression in the audio-visual condition correlated with independent dystonia clinical ratings (r = 0.70, P = 0.04). These findings confirm that overexcitability of the sensorimotor system is a robust feature of dystonia. The presence of elevated normal motor-related activation pattern expression in the non-motor condition suggests that abnormal integration of audio-visual input with sensorimotor network activity is an important trait feature of this disorder. Lastly, quantification of normal motor-related activation pattern expression in individual cases may have utility as an objective descriptor of therapeutic response in trials of new treatments for dystonia and related disorders.
Collapse
Affiliation(s)
- Maren Carbon
- Centre for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, New York 11030, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Simonyan K, Ludlow CL. Abnormal activation of the primary somatosensory cortex in spasmodic dysphonia: an fMRI study. ACTA ACUST UNITED AC 2010; 20:2749-59. [PMID: 20194686 DOI: 10.1093/cercor/bhq023] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Spasmodic dysphonia (SD) is a task-specific focal dystonia of unknown pathophysiology, characterized by involuntary spasms in the laryngeal muscles during speaking. Our aim was to identify symptom-specific functional brain activation abnormalities in adductor spasmodic dysphonia (ADSD) and abductor spasmodic dysphonia (ABSD). Both SD groups showed increased activation extent in the primary sensorimotor cortex, insula, and superior temporal gyrus during symptomatic and asymptomatic tasks and decreased activation extent in the basal ganglia, thalamus, and cerebellum during asymptomatic tasks. Increased activation intensity in SD patients was found only in the primary somatosensory cortex during symptomatic voice production, which showed a tendency for correlation with ADSD symptoms. Both SD groups had lower correlation of activation intensities between the primary motor and sensory cortices and additional correlations between the basal ganglia, thalamus, and cerebellum during symptomatic and asymptomatic tasks. Compared with ADSD patients, ABSD patients had larger activation extent in the primary sensorimotor cortex and ventral thalamus during symptomatic task and in the inferior temporal cortex and cerebellum during symptomatic and asymptomatic voice production. The primary somatosensory cortex shows consistent abnormalities in activation extent, intensity, correlation with other brain regions, and symptom severity in SD patients and, therefore, may be involved in the pathophysiology of SD.
Collapse
Affiliation(s)
- Kristina Simonyan
- Laryngeal and Speech Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bathesda, MD 20892, USA.
| | | |
Collapse
|
47
|
Peterson DA, Sejnowski TJ, Poizner H. Convergent evidence for abnormal striatal synaptic plasticity in dystonia. Neurobiol Dis 2010; 37:558-73. [PMID: 20005952 PMCID: PMC2846420 DOI: 10.1016/j.nbd.2009.12.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 11/30/2009] [Accepted: 12/03/2009] [Indexed: 11/24/2022] Open
Abstract
Dystonia is a functionally disabling movement disorder characterized by abnormal movements and postures. Although substantial recent progress has been made in identifying genetic factors, the pathophysiology of the disease remains a mystery. A provocative suggestion gaining broader acceptance is that some aspect of neural plasticity may be abnormal. There is also evidence that, at least in some forms of dystonia, sensorimotor "use" may be a contributing factor. Most empirical evidence of abnormal plasticity in dystonia comes from measures of sensorimotor cortical organization and physiology. However, the basal ganglia also play a critical role in sensorimotor function. Furthermore, the basal ganglia are prominently implicated in traditional models of dystonia, are the primary targets of stereotactic neurosurgical interventions, and provide a neural substrate for sensorimotor learning influenced by neuromodulators. Our working hypothesis is that abnormal plasticity in the basal ganglia is a critical link between the etiology and pathophysiology of dystonia. In this review we set up the background for this hypothesis by integrating a large body of disparate indirect evidence that dystonia may involve abnormalities in synaptic plasticity in the striatum. After reviewing evidence implicating the striatum in dystonia, we focus on the influence of two neuromodulatory systems: dopamine and acetylcholine. For both of these neuromodulators, we first describe the evidence for abnormalities in dystonia and then the means by which it may influence striatal synaptic plasticity. Collectively, the evidence suggests that many different forms of dystonia may involve abnormal plasticity in the striatum. An improved understanding of these altered plastic processes would help inform our understanding of the pathophysiology of dystonia, and, given the role of the striatum in sensorimotor learning, provide a principled basis for designing therapies aimed at the dynamic processes linking etiology to pathophysiology of the disease.
Collapse
Affiliation(s)
- David A Peterson
- Institute for Neural Computation, University of California at San Diego, San Diego Supercomputer Center-Annex, 0523, Level B-1, South Wing, B108E, La Jolla, CA 92093-0523, USA.
| | | | | |
Collapse
|
48
|
Nahab FB, Hallett M. Current role of functional MRI in the diagnosis of movement disorders. Neuroimaging Clin N Am 2010; 20:103-10. [PMID: 19959022 DOI: 10.1016/j.nic.2009.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The functional magnetic resonance (fMR) technique for brain mapping is a valuable tool for understanding both normal physiology and the dysfunction taking place in disorders of the brain. This article provides an overview of fMR imaging methods and their applications in the study of neurologic movement disorders. The article also reviews the current neuroimaging literature regarding parkinsonisms, dystonia, essential tremor, and Huntington disease, and includes a discussion of current methodological limitations and future directions for this exciting field.
Collapse
Affiliation(s)
- Fatta B Nahab
- University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | | |
Collapse
|
49
|
CARBON MAREN, EIDELBERG DAVID. Abnormal structure-function relationships in hereditary dystonia. Neuroscience 2009; 164:220-9. [PMID: 19162138 PMCID: PMC2760608 DOI: 10.1016/j.neuroscience.2008.12.041] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 12/17/2008] [Accepted: 12/21/2008] [Indexed: 12/01/2022]
Abstract
Primary torsion dystonia (PTD) is a chronic movement disorder manifested clinically by focal or generalized sustained muscle contractions, postures, and/or involuntary movements. The most common inherited form of PTD is associated with the DYT1 mutation on chromosome 9q34. A less frequent form is linked to the DYT6 locus on chromosome 8q21-22. Both forms are autosomal dominant with incomplete (approximately 30%) clinical penetrance. Extensive functional and microstructural imaging with positron emission tomography (PET) and diffusion tensor MRI (DTI) has been performed on manifesting and non-manifesting carriers of these mutations. The results are consistent with the view of PTD as a neurodevelopmental circuit disorder involving cortico-striatal-pallido-thalamocortical (CSPTC) and related cerebellar-thalamo-cortical pathways. Studies of resting regional metabolism have revealed consistent abnormalities in PTD involving multiple interconnected elements of these circuits. In gene carriers, changes in specific subsets of these regions have been found to relate to genotype, phenotype, or both. For instance, genotypic abnormalities in striatal metabolic activity parallel previously reported reductions in local D(2) receptor availability. Likewise, we have identified a unique penetrance-related metabolic network characterized by increases in the pre-supplementary motor area (SMA) and parietal association areas, associated with relative reductions in the cerebellum, brainstem, and ventral thalamus. Interestingly, metabolic activity in the hypermetabolic areas has recently been found to be modified by the penetrance regulating D216H polymorphism. The DTI data raise the possibility that metabolic abnormalities in mutation carriers reflect adaptive responses to developmental abnormalities in the intrinsic connectivity of the motor pathways. Moreover, findings of increased motor activation responses in these subjects are compatible with the reductions in cortical inhibition that have been observed in this disorder. Future research will focus on clarifying the relationship of these changes to clinical penetrance in dystonia mutation carriers, and the reversibility of disease-related functional abnormalities by treatment.
Collapse
Affiliation(s)
- MAREN CARBON
- Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore – Long Island Jewish Health System, 350 Community Drive, Manhasset, NY 11030, USA and Departments of Neurology and Medicine, North Shore University Hospital, 300 Community Drive, Manhasset, New York, and New York University School of Medicine, 550 First Avenue New York, NY 10016, USA
| | - DAVID EIDELBERG
- Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore – Long Island Jewish Health System, 350 Community Drive, Manhasset, NY 11030, USA and Departments of Neurology and Medicine, North Shore University Hospital, 300 Community Drive, Manhasset, New York, and New York University School of Medicine, 550 First Avenue New York, NY 10016, USA
| |
Collapse
|
50
|
Griffiths PD, Radon MR, Crossman AR, Zurakowski D, Connolly DJ. Anatomic localization of dyskinesia in children with "profound" perinatal hypoxic-ischemic injury. AJNR Am J Neuroradiol 2009; 31:436-41. [PMID: 19875467 DOI: 10.3174/ajnr.a1854] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE CP is a common feature of perinatal HIBD in the context of "acute profound" injury, and in this article, we have studied the possible anatomic substrates of dyskinesia. We have reviewed the extent of brain injury in children with dyskinetic and spastic CP due to acute profound hypoxia to identify sites of injury that explain why only some children develop movement disorders. It is known that the STN has a role in the development of movement disorders; therefore, we have specifically studied it. MATERIALS AND METHODS We retrospectively reviewed MR imaging of 40 consecutive children referred to our center with CP confirmed to be due to acute profound hypoxic-ischemic injury. All children received the same high-resolution MR imaging protocol with the same 1.5T scanner. Two pediatric neuroradiologists reviewed the imaging. Logistic regression was applied to identify multivariable predictors that differentiate dyskinetic and spastic CP. RESULTS Twenty children had dyskinetic CP and 20 had spastic CP. Children with dyskinetic CP had more frequent injury to the STN, as manifest by increased T2 signal intensity. Children with spastic CP had more severe damage to white matter in the vicinity of the paracentral lobule. Injuries to the putamen, caudate, and globus pallidus were not significant predictors of dyskinesia. CONCLUSIONS We have shown an association between hypoxic-ischemic injury to the STN at birth and the emergence of dyskinesia later in life.
Collapse
Affiliation(s)
- P D Griffiths
- Academic Unit of Radiology, University of Sheffield, Sheffield, UK
| | | | | | | | | |
Collapse
|