1
|
Passaretti M, Piervincenzi C, Baione V, Pasqua G, Colella D, Pietracupa S, Petsas N, Angelini L, Cannavacciuolo A, Paparella G, Berardelli A, Pantano P, Bologna M. The Role of Cerebellum and Basal Ganglia Functional Connectivity in Altered Voluntary Movement Execution in Essential Tremor. CEREBELLUM (LONDON, ENGLAND) 2024:10.1007/s12311-024-01699-6. [PMID: 38761352 DOI: 10.1007/s12311-024-01699-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/25/2024] [Indexed: 05/20/2024]
Abstract
Substantial evidence highlights the role of the cerebellum in the pathophysiology of tremor in essential tremor (ET), although its potential involvement in altered movement execution in this condition remains unclear. This study aims to explore potential correlations between the cerebellum and basal ganglia functional connectivity and voluntary movement execution abnormalities in ET, objectively assessed with kinematic techniques. A total of 20 patients diagnosed with ET and 18 healthy subjects were enrolled in this study. Tremor and repetitive finger tapping were recorded using an optoelectronic kinematic system. All participants underwent comprehensive 3T-MRI examinations, including 3D-T1 and blood-oxygen-level dependent (BOLD) sequences during resting state. Morphometric analysis was conducted on the 3D-T1 images, while a seed-based analysis was performed to investigate the resting-state functional connectivity (rsFC) of dorsal and ventral portions of the dentate nucleus and the external and internal segments of the globus pallidus. Finally, potential correlations between rsFC alterations in patients and clinical as well as kinematic scores were assessed. Finger tapping movements were slower in ET than in healthy subjects. Compared to healthy subjects, patients with ET exhibited altered FC of both dentate and globus pallidus with cerebellar, basal ganglia, and cortical areas. Interestingly, both dentate and pallidal FC exhibited positive correlations with movement velocity in patients, differently from that we observed in healthy subjects, indicating the higher the FC, the faster the finger tapping. The findings of this study indicate the possible role of both cerebellum and basal ganglia in the pathophysiology of altered voluntary movement execution in patients with ET.
Collapse
Affiliation(s)
- Massimiliano Passaretti
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Claudia Piervincenzi
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
| | - Viola Baione
- Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Gabriele Pasqua
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
| | - Donato Colella
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
| | - Sara Pietracupa
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
- IRCCS Neuromed, Pozzilli, IS, Italy
| | - Nikolaos Petsas
- Department of Public Health and Infectious Disease, Sapienza University of Rome, Rome, Italy
| | | | | | - Giulia Paparella
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
- IRCCS Neuromed, Pozzilli, IS, Italy
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
- IRCCS Neuromed, Pozzilli, IS, Italy
| | - Patrizia Pantano
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy
- IRCCS Neuromed, Pozzilli, IS, Italy
| | - Matteo Bologna
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185, Rome, Italy.
- IRCCS Neuromed, Pozzilli, IS, Italy.
| |
Collapse
|
2
|
Angelini L, Paparella G, Cannavacciuolo A, Costa D, Birreci D, De Riggi M, Passaretti M, Colella D, Guerra A, Berardelli A, Bologna M. Clinical and kinematic characterization of parkinsonian soft signs in essential tremor. J Neural Transm (Vienna) 2024:10.1007/s00702-024-02784-0. [PMID: 38744708 DOI: 10.1007/s00702-024-02784-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/06/2024] [Indexed: 05/16/2024]
Abstract
BACKGROUND Subtle parkinsonian signs, i.e., rest tremor and bradykinesia, are considered soft signs for defining essential tremor (ET) plus. OBJECTIVES Our study aimed to further characterize subtle parkinsonian signs in a relatively large sample of ET patients from a clinical and neurophysiological perspective. METHODS We employed clinical scales and kinematic techniques to assess a sample of 82 ET patients. Eighty healthy controls matched for gender and age were also included. The primary focus of our study was to conduct a comparative analysis of ET patients (without any soft signs) and ET-plus patients with rest tremor and/or bradykinesia. Additionally, we investigated the asymmetry and side concordance of these soft signs. RESULTS In ET-plus patients with parkinsonian soft signs (56.10% of the sample), rest tremor was clinically observed in 41.30% of cases, bradykinesia in 30.43%, and rest tremor plus bradykinesia in 28.26%. Patients with rest tremor had more severe and widespread action tremor than other patients. Furthermore, we observed a positive correlation between the amplitude of action and rest tremor. Most ET-plus patients had an asymmetry of rest tremor and bradykinesia. There was no side concordance between these soft signs, as confirmed through both clinical examination and kinematic evaluation. CONCLUSIONS Rest tremor and bradykinesia are frequently observed in ET and are often asymmetric but not concordant. Our findings provide a better insight into the phenomenology of ET and suggest that the parkinsonian soft signs (rest tremor and bradykinesia) in ET-plus may originate from distinct pathophysiological mechanisms.
Collapse
Affiliation(s)
- Luca Angelini
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
| | - Giulia Paparella
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | | | - Davide Costa
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
| | - Daniele Birreci
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Martina De Riggi
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Massimiliano Passaretti
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Donato Colella
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Andrea Guerra
- Parkinson and Movement Disorders Unit, Study Center on Neurodegeneration (CESNE), Department of Neuroscience, University of Padua, Padua, Italy
- Padova Neuroscience Center (PNC), University of Padua, Padua, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Matteo Bologna
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy.
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy.
| |
Collapse
|
3
|
Colella D, Passaretti M, Frantellizzi V, Silvia De Feo M, Cannavacciuolo A, Angelini L, Birreci D, Costa D, Paparella G, Guerra A, De Vincentis G, Berardelli A, Bologna M. Subtle changes in central dopaminergic tone underlie bradykinesia in essential tremor. Neuroimage Clin 2023; 40:103526. [PMID: 37847966 PMCID: PMC10587600 DOI: 10.1016/j.nicl.2023.103526] [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: 07/30/2023] [Revised: 09/25/2023] [Accepted: 10/09/2023] [Indexed: 10/19/2023]
Abstract
INTRODUCTION In this research, our primary objective was to explore the correlation between basal ganglia dopaminergic neurotransmission, assessed using 123I-FP-CIT (DAT-SPECT), and finger movements abnormalities in patients with essential tremor (ET) and Parkinson's disease (PD). METHODS We enrolled 16 patients with ET, 17 with PD, and 18 healthy controls (HC). Each participant underwent comprehensive clinical evaluations, kinematic assessments of finger tapping. ET and PD patients underwent DAT-SPECT imaging. The DAT-SPECT scans were subjected to both visual and semi-quantitative analysis using DaTQUANT®. We then investigated the correlations between the clinical, kinematic, and DAT-SPECT data, in patients. RESULTS Our findings confirm that individuals with ET exhibited slower finger tapping than HC. Visual evaluation of radiotracer uptake in both striata demonstrated normal levels within the ET patient cohort, while PD patients displayed reduced uptake. However, there was notable heterogeneity in the quantification of uptake within the striata among ET patients. Additionally, we found a correlation between the amount of radiotracer uptake in the striatum and movement velocity during finger tapping in patients. Specifically, lower radioligand uptake corresponded to decreased movement velocity (ET: coef. = 0.53, p-adj = 0.03; PD: coef. = 0.59, p-adj = 0.01). CONCLUSION The study's findings suggest a potential link between subtle changes in central dopaminergic tone and altered voluntary movement execution, in ET. These results provide further insights into the pathophysiology of ET. However, longitudinal studies are essential to determine whether the slight reduction in dopaminergic tone observed in ET patients represents a distinct subtype of the disease or could serve as a predictor for the clinical progression into PD.
Collapse
Affiliation(s)
- Donato Colella
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Massimiliano Passaretti
- Department of Human Neurosciences, Sapienza University of Rome, Italy; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Viviana Frantellizzi
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Italy
| | - Maria Silvia De Feo
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Italy
| | | | - Luca Angelini
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Daniele Birreci
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Davide Costa
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Giulia Paparella
- Department of Human Neurosciences, Sapienza University of Rome, Italy; IRCCS Neuromed Pozzilli (IS), Italy
| | - Andrea Guerra
- Parkinson and Movement Disorder Unit, Study Center on Neurodegeneration (CESNE), Department of Neuroscience, University of Padua, Padua, Italy
| | - Giuseppe De Vincentis
- Department of Radiological Sciences, Oncology and Anatomical Pathology, Sapienza University of Rome, Italy
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza University of Rome, Italy; IRCCS Neuromed Pozzilli (IS), Italy
| | - Matteo Bologna
- Department of Human Neurosciences, Sapienza University of Rome, Italy; IRCCS Neuromed Pozzilli (IS), Italy.
| |
Collapse
|
4
|
Song J, Kim K, Park J. Multi-muscle Synergies of Postural Control in Self- and External-Triggered Force Release During Simulated Archery Shooting. J Mot Behav 2023; 55:289-301. [PMID: 36919981 DOI: 10.1080/00222895.2023.2187336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
We investigated postural stability during simulated archery shooting. The experiment consisted of two force release conditions: self-triggered (time-set in a feedforward fashion) and external cue-triggered (time-set by reacting to external cue) conditions while standing on the force platform. The electromyography of leg muscles and the center of pressure (COP) were recorded. The notions of muscle-modes (M-modes) and multi-muscle synergies were employed to quantify the postural stability, which described covariation patterns of the M-modes to stabilize the COP. The result showed relatively strong postural stability in a self-triggered condition associated with consistent shooting performance. The current findings suggested that initiating force release in a feedforward fashion would be a beneficial strategy to ensure the consistency in shooting performance.
Collapse
Affiliation(s)
- Junkyung Song
- Department of Physical Education, Seoul National University, Seoul, South Korea
| | - Kitae Kim
- Korea Institute of Sport Science, Seoul, South Korea
| | - Jaebum Park
- Department of Physical Education, Seoul National University, Seoul, South Korea.,Institute of Sport Science, Seoul National University, Seoul, South Korea.,Advanced Institute of Convergence Science, Seoul National University, Seoul, South Korea.,Department of AI-Integrated Education, Seoul National University, Seoul, South Korea
| |
Collapse
|
5
|
Paparella G, Cannavacciuolo A, Angelini L, Costa D, Birreci D, Alunni Fegatelli D, Guerra A, Berardelli A, Bologna M. May Bradykinesia Features Aid in Distinguishing Parkinson's Disease, Essential Tremor, And Healthy Elderly Individuals? JOURNAL OF PARKINSON'S DISEASE 2023; 13:1047-1060. [PMID: 37522221 PMCID: PMC10578222 DOI: 10.3233/jpd-230119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/11/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND Bradykinesia is the hallmark feature of Parkinson's disease (PD); however, it can manifest in other conditions, including essential tremor (ET), and in healthy elderly individuals. OBJECTIVE Here we assessed whether bradykinesia features aid in distinguishing PD, ET, and healthy elderly individuals. METHODS We conducted simultaneous video and kinematic recordings of finger tapping in 44 PD patients, 69 ET patients, and 77 healthy elderly individuals. Videos were evaluated blindly by expert neurologists. Kinematic recordings were blindly analyzed. We calculated the inter-raters agreement and compared data among groups. Density plots assessed the overlapping in the distribution of kinematic data. Regression analyses and receiver operating characteristic curves determined how the kinematics influenced the likelihood of belonging to a clinical score category and diagnostic group. RESULTS The inter-rater agreement was fair (Fleiss K = 0.32). Rater found the highest clinical scores in PD, and higher scores in ET than healthy elderly individuals (p < 0.001). In regard to kinematic analysis, the groups showed variations in movement velocity, with PD presenting the slowest values and ET displaying less velocity than healthy elderly individuals (all ps < 0.001). Additionally, PD patients showed irregular rhythm and sequence effect. However, kinematic data significantly overlapped. Regression analyses showed that kinematic analysis had high specificity in differentiating between PD and healthy elderly individuals. Nonetheless, accuracy decreased when evaluating subjects with intermediate kinematic values, i.e., ET patients. CONCLUSION Despite a considerable degree of overlap, bradykinesia features vary to some extent in PD, ET, and healthy elderly individuals. Our findings have implications for defining bradykinesia and categorizing patients.
Collapse
Affiliation(s)
- Giulia Paparella
- IRCCS Neuromed, Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | | | - Luca Angelini
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Davide Costa
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Daniele Birreci
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Danilo Alunni Fegatelli
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome,Italy
| | - Andrea Guerra
- Parkinson and Movement Disorders Unit, Study Center on Neurodegeneration (CESNE), University of Padua, Padua, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| | - Matteo Bologna
- IRCCS Neuromed, Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Italy
| |
Collapse
|
6
|
Parkinsonism and tremor syndromes. J Neurol Sci 2021; 433:120018. [PMID: 34686357 DOI: 10.1016/j.jns.2021.120018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/06/2021] [Accepted: 09/29/2021] [Indexed: 01/22/2023]
Abstract
Tremor, the most common movement disorder, may occur in isolation or may co-exist with a variety of other neurologic and movement disorders including parkinsonism, dystonia, and ataxia. When associated with Parkinson's disease, tremor may be present at rest or as an action tremor overlapping in phenomenology with essential tremor. Essential tremor may be associated not only with parkinsonism but other neurological disorders, suggesting the possibility of essential tremor subtypes. Besides Parkinson's disease, tremor can be an important feature of other parkinsonian disorders, such as atypical parkinsonism and drug-induced parkinsonism. In addition, tremor can be a prominent feature in patients with other movement disorders such as fragile X-associated tremor/ataxia syndrome, and Wilson's disease in which parkinsonian features may be present. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.
Collapse
|
7
|
Cikajlo I, Pogačnik M. Movement analysis of pick-and-place virtual reality exergaming in patients with Parkinson's disease. Technol Health Care 2021; 28:391-402. [PMID: 32200361 DOI: 10.3233/thc-191700] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Reduced coordination of precise small movements of the hand, wrist and fingers in Parkinson's disease (PD) has been mostly solved by medications and deep brain stimulation. The effects have been evaluated by clinical tests only. OBJECTIVE Virtual reality-based exergaming may enhance fine movements, decrease the medications dosage and provide an additional non-subjective evaluation. METHODS 3D pick-and-place task (10Cubes) has been developed in a virtual world. The person placed the virtual cubes by the virtual hand, an avatar of the real hand tracked by a Leap Motion Controller (LMC). The system computed the time of manipulating the cube, the total time, the average time, the speed, and the distance. It counted and managed the number of cubes touched, and calculated the hand shake level, i.e. the average tremor index. A pilot test was carried out in a healthy neurologically intact person and a patient with PD using a 3D head-mounted device (HMD) or LCD screen. RESULTS The results indicate that substantial and also statistically significant (p< 0.05) differences exist between both participants in all objective parameters; the most noteworthy is the average tremor index. However, we found the parameters only marginally different with 2D equipment. CONCLUSIONS The evaluation system of 10Cubes has proved applicable at an unchanged medication plan, but its clinical effectiveness could be confirmed with a randomized study.
Collapse
Affiliation(s)
- Imre Cikajlo
- University Rehabilitation Institute, SI-1000 Ljubljana, Slovenia.,School of Engineering and Management, University of Nova Gorica, SI-5000 Nova Gorica, Slovenia
| | - Matevž Pogačnik
- Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| |
Collapse
|
8
|
Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Álvarez I, Pastor P, Agúndez JAG. Genomic Markers for Essential Tremor. Pharmaceuticals (Basel) 2021; 14:ph14060516. [PMID: 34072005 PMCID: PMC8226734 DOI: 10.3390/ph14060516] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/23/2021] [Accepted: 05/24/2021] [Indexed: 12/13/2022] Open
Abstract
There are many reports suggesting an important role of genetic factors in the etiopathogenesis of essential tremor (ET), encouraging continuing the research for possible genetic markers. Linkage studies in families with ET have identified 4 genes/loci for familial ET, although the responsible gene(s) have not been identified. Genome-wide association studies (GWAS) described several variants in LINGO1, SLC1A2, STK32B, PPARGC1A, and CTNNA3, related with ET, but none of them have been confirmed in replication studies. In addition, the case-control association studies performed for candidate variants have not convincingly linked any gene with the risk for ET. Exome studies described the association of several genes with familial ET (FUS, HTRA2, TENM4, SORT1, SCN11A, NOTCH2NLC, NOS3, KCNS2, HAPLN4, USP46, CACNA1G, SLIT3, CCDC183, MMP10, and GPR151), but they were found only in singular families and, again, not found in other families or other populations, suggesting that some can be private polymorphisms. The search for responsible genes for ET is still ongoing.
Collapse
Affiliation(s)
- Félix Javier Jiménez-Jiménez
- Section of Neurology, Hospital Universitario del Sureste, E28500 Arganda del Rey, Spain;
- Correspondence: ; Tel.: +34-636-96-83-95; Fax: +34-913-28-07-04
| | | | - Elena García-Martín
- ARADyAL Instituto de Salud Carlos III, University Institute of Molecular Pathology Biomarkers, University of Extremadura, E10071 Caceres, Spain; (E.G.-M.); (J.A.G.A.)
| | - Ignacio Álvarez
- Movement Disorders Unit, Department of Neurology, University Hospital Mútua de Terrassa, Fundació Docencia i Recerça Mútua de Terrassa, E08221 Terrassa, Spain; (I.Á.); (P.P.)
| | - Pau Pastor
- Movement Disorders Unit, Department of Neurology, University Hospital Mútua de Terrassa, Fundació Docencia i Recerça Mútua de Terrassa, E08221 Terrassa, Spain; (I.Á.); (P.P.)
| | - José A. G. Agúndez
- ARADyAL Instituto de Salud Carlos III, University Institute of Molecular Pathology Biomarkers, University of Extremadura, E10071 Caceres, Spain; (E.G.-M.); (J.A.G.A.)
| |
Collapse
|
9
|
Paparella G, Fasano A, Hallett M, Berardelli A, Bologna M. Emerging concepts on bradykinesia in non-parkinsonian conditions. Eur J Neurol 2021; 28:2403-2422. [PMID: 33793037 DOI: 10.1111/ene.14851] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND PURPOSE Bradykinesia is one of the cardinal motor symptoms of Parkinson's disease. However, clinical and experimental studies indicate that bradykinesia may also be observed in various neurological diseases not primarily characterized by parkinsonism. These conditions include hyperkinetic movement disorders, such as dystonia, chorea, and essential tremor. Bradykinesia may also be observed in patients with neurological conditions that are not seen as "movement disorders," including those characterized by the involvement of the cerebellum and corticospinal system, dementia, multiple sclerosis, and psychiatric disorders. METHODS We reviewed clinical reports and experimental studies on bradykinesia in non-parkinsonian conditions and discussed the major findings. RESULTS Bradykinesia is a common motor abnormality in non-parkinsonian conditions. From a pathophysiological standpoint, bradykinesia in neurological conditions not primarily characterized by parkinsonism may be explained by brain network dysfunction. CONCLUSION In addition to the pathophysiological implications, the present paper highlights important terminological issues and the need for a new, more accurate, and more widely used definition of bradykinesia in the context of movement disorders and other neurological conditions.
Collapse
Affiliation(s)
| | - Alfonso Fasano
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada.,Division of Neurology, University of Toronto, Toronto, Ontario, Canada.,Krembil Brain Institute, Toronto, Ontario, Canada
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Alfredo Berardelli
- IRCCS Neuromed, Pozzilli, Italy.,Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
| | - Matteo Bologna
- IRCCS Neuromed, Pozzilli, Italy.,Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
| |
Collapse
|
10
|
Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Agúndez JAG. Sleep disorders in essential tremor: systematic review and meta-analysis. Sleep 2021; 43:5804186. [PMID: 32163585 DOI: 10.1093/sleep/zsaa039] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 02/19/2020] [Indexed: 12/20/2022] Open
Abstract
Sleep disorders are frequent in patients diagnosed with essential tremor (ET). The present review focuses on sleep disorders and the results of polysomnographic studies performed in patients with ET. For this purpose we performed a systematic review crossing the search term "essential tremor" with "sleep," "sleep disorders," "sleep disturbances" and "polysomnography," and with specific sleep disorders, according to the International Classification of the Sleep Disorders-Third Edition, using the PubMed, EMBASE, MEDLINE, and Web of Science Databases. The most frequent sleep problems reported by patients with ET were the bad quality of sleep and excessive daytime somnolence (the latter could be related to drugs commonly used for the treatment of ET). Probable rapid eye movement sleep behavior disorder, coexistent restless legs syndrome, insomnia, and nocturia were not infrequent complaints, while the presence of other sleep disorders in patients with ET was restricted to anecdotal reports or not described. Meta-analyses of previous reports showed that patients with ET (according to the PRISMA and MOOSE guidelines) showed higher scores in the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale than controls and lower scores than those of patients diagnosed with Parkinson's disease. Studies using polysomnography in patients with ET are scarce and do not permit to establish valid conclusions regarding polysomnographic features in this disorder.
Collapse
Affiliation(s)
| | | | - Elena García-Martín
- University Institute of Molecular Pathology Biomarkers, UNEx. ARADyAL Instituto de Salud Carlos III, Cáceres, Spain
| | - José A G Agúndez
- University Institute of Molecular Pathology Biomarkers, UNEx. ARADyAL Instituto de Salud Carlos III, Cáceres, Spain
| |
Collapse
|
11
|
Louis ED. The Essential Tremors: Evolving Concepts of a Family of Diseases. Front Neurol 2021; 12:650601. [PMID: 33841316 PMCID: PMC8032967 DOI: 10.3389/fneur.2021.650601] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/12/2021] [Indexed: 12/31/2022] Open
Abstract
The past 10 years has seen a remarkable advance in our understanding of the disease traditionally referred to as “essential tremor” (ET). First, the clinical phenotype of ET has been expanded from that of a bland, unidimensional, and monosymptomatic entity to one with a host of heterogeneous features. These features include a broader and more nuanced collection of tremors, non-tremor motor features (e.g., gait abnormalities) and a range of non-motor features, including cognitive, psychiatric, sleep, and other abnormalities. The natural history of these features, as well as their relationships with one another and with disease duration and severity, are better appreciated than they were previously. Studies of disease etiology have identified a number of candidate genes as well as explored several environmental determinants of disease. In addition, the decade has seen the beginnings and expansion of rigorous postmortem studies that have identified and described the postmortem changes in the brains of patients with ET. This emerging science has given rise to a new notion that the disease, in many cases, is one of cerebellar system degeneration. Across all of these studies (clinical, etiological, and pathophysiological) is the observation that there is heterogeneity across patients and that “essential tremor” is likely not a single disease but, rather, a family of diseases. The time has come to use the more appropriate terminology, “the essential tremors,” to fully describe and encapsulate what is now apparent. In this paper, the author will review the clinical, etiological, and pathophysiological findings, referred to above, and make the argument that the terminology should evolve to reflect advances in science and that “the essential tremors” is a more scientifically appropriate term.
Collapse
Affiliation(s)
- Elan D Louis
- Department of Neurology, University of Texas Southwestern, Dallas, TX, United States
| |
Collapse
|
12
|
Abstract
PURPOSE OF THE REVIEW Patients diagnosed with essential tremor (ET) report frequent sleep complaints. This review focuses on the main findings of studies addressing sleep features in patients diagnosed with ET, updating previously reported information. Bad quality of sleep and excessive daytime somnolence are very frequent in patients with ET, although the effects of the drugs used for the therapy of ET could contribute to these complaints. REM sleep behavior disorder, restless legs, insomnia, and nocturia are frequent complaints as well. There is a lack of studies addressing polysomnographic features of ET.
Collapse
|
13
|
Bologna M, Paparella G, Colella D, Cannavacciuolo A, Angelini L, Alunni‐Fegatelli D, Guerra A, Berardelli A. Is there evidence of bradykinesia in essential tremor? Eur J Neurol 2020; 27:1501-1509. [DOI: 10.1111/ene.14312] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 05/04/2020] [Indexed: 12/15/2022]
Affiliation(s)
- M. Bologna
- Department of Human Neurosciences Sapienza University of Rome RomeItaly
- IRCCS Neuromed Pozzilli (IS)Italy
| | | | - D. Colella
- Department of Human Neurosciences Sapienza University of Rome RomeItaly
| | - A. Cannavacciuolo
- Department of Human Neurosciences Sapienza University of Rome RomeItaly
| | - L. Angelini
- Department of Human Neurosciences Sapienza University of Rome RomeItaly
| | - D. Alunni‐Fegatelli
- Department of Public Health and Infectious Disease Sapienza University of Rome Rome Italy
| | | | - A. Berardelli
- Department of Human Neurosciences Sapienza University of Rome RomeItaly
- IRCCS Neuromed Pozzilli (IS)Italy
| |
Collapse
|
14
|
Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Agúndez JA. An Update on the Neurochemistry of Essential Tremor. Curr Med Chem 2020; 27:1690-1710. [DOI: 10.2174/0929867325666181112094330] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 09/03/2018] [Accepted: 11/05/2018] [Indexed: 12/21/2022]
Abstract
Background:
The pathophysiology and neurochemical mechanisms of essential
tremor (ET) are not fully understood, because only a few post-mortem studies have been reported,
and there is a lack of good experimental model for this disease.
Objective:
The main aim of this review is to update data regarding the neurochemical features
of ET. Alterations of certain catecholamine systems, the dopaminergic, serotonergic,
GABAergic, noradrenergic, and adrenergic systems have been described, and are the object of
this revision.
Methods:
For this purpose, we performed a literature review on alterations of the neurotransmitter
or neuromodulator systems (catecholamines, gammaaminobutyric acid or GABA,
excitatory amino acids, adenosine, T-type calcium channels) in ET patients (both post-mortem
or in vivo) or in experimental models resembling ET.
Results and Conclusion:
The most consistent data regarding neurochemistry of ET are related
with the GABAergic and glutamatergic systems, with a lesser contribution of adenosine
and dopaminergic and adrenergic systems, while there is not enough evidence of a definite
role of other neurotransmitter systems in ET. The improvement of harmaline-induced tremor
in rodent models achieved with T-type calcium channel antagonists, cannabinoid 1 receptor,
sphingosine-1-phosphate receptor agonists, and gap-junction blockers, suggests a potential
role of these structures in the pathogenesis of ET.
Collapse
Affiliation(s)
| | | | - Elena García-Martín
- University Institute of Molecular Pathology Biomarkers, UNEx. ARADyAL Instituto de Salud Carlos III, Caceres, Spain
| | - José A.G. Agúndez
- University Institute of Molecular Pathology Biomarkers, UNEx. ARADyAL Instituto de Salud Carlos III, Caceres, Spain
| |
Collapse
|
15
|
Benito-León J, Sanz-Morales E, Melero H, Louis ED, Romero JP, Rocon E, Malpica N. Graph theory analysis of resting-state functional magnetic resonance imaging in essential tremor. Hum Brain Mapp 2019; 40:4686-4702. [PMID: 31332912 DOI: 10.1002/hbm.24730] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/05/2019] [Accepted: 07/08/2019] [Indexed: 11/10/2022] Open
Abstract
Essential tremor (ET) is a neurological disease with both motor and nonmotor manifestations; however, little is known about its underlying brain basis. Furthermore, the overall organization of the brain network in ET remains largely unexplored. We investigated the topological properties of brain functional network, derived from resting-state functional magnetic resonance imaging (MRI) data, in 23 ET patients versus 23 healthy controls. Graph theory analysis was used to assess the functional network organization. At the global level, the functional network of ET patients was characterized by lower small-worldness values than healthy controls-less clustered functionality of the brain. At the regional level, compared with the healthy controls, ET patients showed significantly higher values of global efficiency, cost and degree, and a shorter average path length in the left inferior frontal gyrus (pars opercularis), right inferior temporal gyrus (posterior division and temporo-occipital part), right inferior lateral occipital cortex, left paracingulate, bilateral precuneus bilaterally, left lingual gyrus, right hippocampus, left amygdala, nucleus accumbens bilaterally, and left middle temporal gyrus (posterior part). In addition, ET patients showed significant higher local efficiency and clustering coefficient values in frontal medial cortex bilaterally, subcallosal cortex, posterior cingulate cortex, parahippocampal gyri bilaterally (posterior division), right lingual gyrus, right cerebellar flocculus, right postcentral gyrus, right inferior semilunar lobule of cerebellum and culmen of vermis. Finally, the right intracalcarine cortex and the left orbitofrontal cortex showed a shorter average path length in ET patients, while the left frontal operculum and the right planum polare showed a higher betweenness centrality in ET patients. In conclusion, the efficiency of the overall brain functional network in ET is disrupted. Further, our results support the concept that ET is a disorder that disrupts widespread brain regions, including those outside of the brain regions responsible for tremor.
Collapse
Affiliation(s)
- Julián Benito-León
- Department of Neurology, University Hospital 12 de Octubre, Madrid, Spain.,Center of Biomedical Network Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Department of Medicine, Faculty of Medicine, Complutense University, Madrid, Spain
| | - Emilio Sanz-Morales
- Medical Image Analysis Laboratory (LAIMBIO), Rey Juan Carlos University, Madrid, Spain
| | - Helena Melero
- Medical Image Analysis Laboratory (LAIMBIO), Rey Juan Carlos University, Madrid, Spain
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut.,Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, Connecticut.,Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, Connecticut
| | - Juan P Romero
- Faculty of Biosanitary Sciences, Francisco de Vitoria University, Madrid, Spain.,Brain Damage Unit, Hospital Beata Maria Ana, Madrid, Spain
| | - Eduardo Rocon
- Neural and Cognitive Engineering group, Center for Automation and Robotics (CAR) CSIC-UPM, Arganda del Rey, Spain
| | - Norberto Malpica
- Medical Image Analysis Laboratory (LAIMBIO), Rey Juan Carlos University, Madrid, Spain
| |
Collapse
|
16
|
Bareš M, Apps R, Avanzino L, Breska A, D'Angelo E, Filip P, Gerwig M, Ivry RB, Lawrenson CL, Louis ED, Lusk NA, Manto M, Meck WH, Mitoma H, Petter EA. Consensus paper: Decoding the Contributions of the Cerebellum as a Time Machine. From Neurons to Clinical Applications. CEREBELLUM (LONDON, ENGLAND) 2019; 18:266-286. [PMID: 30259343 DOI: 10.1007/s12311-018-0979-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Time perception is an essential element of conscious and subconscious experience, coordinating our perception and interaction with the surrounding environment. In recent years, major technological advances in the field of neuroscience have helped foster new insights into the processing of temporal information, including extending our knowledge of the role of the cerebellum as one of the key nodes in the brain for this function. This consensus paper provides a state-of-the-art picture from the experts in the field of the cerebellar research on a variety of crucial issues related to temporal processing, drawing on recent anatomical, neurophysiological, behavioral, and clinical research.The cerebellar granular layer appears especially well-suited for timing operations required to confer millisecond precision for cerebellar computations. This may be most evident in the manner the cerebellum controls the duration of the timing of agonist-antagonist EMG bursts associated with fast goal-directed voluntary movements. In concert with adaptive processes, interactions within the cerebellar cortex are sufficient to support sub-second timing. However, supra-second timing seems to require cortical and basal ganglia networks, perhaps operating in concert with cerebellum. Additionally, sensory information such as an unexpected stimulus can be forwarded to the cerebellum via the climbing fiber system, providing a temporally constrained mechanism to adjust ongoing behavior and modify future processing. Patients with cerebellar disorders exhibit impairments on a range of tasks that require precise timing, and recent evidence suggest that timing problems observed in other neurological conditions such as Parkinson's disease, essential tremor, and dystonia may reflect disrupted interactions between the basal ganglia and cerebellum.The complex concepts emerging from this consensus paper should provide a foundation for further discussion, helping identify basic research questions required to understand how the brain represents and utilizes time, as well as delineating ways in which this knowledge can help improve the lives of those with neurological conditions that disrupt this most elemental sense. The panel of experts agrees that timing control in the brain is a complex concept in whom cerebellar circuitry is deeply involved. The concept of a timing machine has now expanded to clinical disorders.
Collapse
Affiliation(s)
- Martin Bareš
- First Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic.
- Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, USA.
| | - Richard Apps
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Laura Avanzino
- Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa, Genoa, Italy
- Centre for Parkinson's Disease and Movement Disorders, Ospedale Policlinico San Martino, Genoa, Italy
| | - Assaf Breska
- Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Egidio D'Angelo
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Brain Connectivity Center, Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IRCCS), Pavia, Italy
| | - Pavel Filip
- First Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Marcus Gerwig
- Department of Neurology, University of Duisburg-Essen, Duisburg, Germany
| | - Richard B Ivry
- Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Charlotte L Lawrenson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - Nicholas A Lusk
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
| | - Mario Manto
- Department of Neurology, CHU-Charleroi, Charleroi, Belgium -Service des Neurosciences, UMons, Mons, Belgium
| | - Warren H Meck
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
| | - Hiroshi Mitoma
- Medical Education Promotion Center, Tokyo Medical University, Tokyo, Japan
| | - Elijah A Petter
- Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
| |
Collapse
|
17
|
Fernandes TMP, Felismino DDSF, Almeida NLD, Santos NAD. Percepção Visual no Tremor Essencial: Uma Revisão Sistemática. PSICOLOGIA: TEORIA E PESQUISA 2019. [DOI: 10.1590/0102.3772e35210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO Investigou-se a relação entre percepção visual e tremor essencial (TE). Realizou-se uma revisão dos estudos publicados sobre o tema nas bases de dados PubMed, BIREME, CINAHL, Web of Science, PsycINFO, SciELO, SCOPUS e ELSEVIER desde a origem até 05 de janeiro de 2017. A triagem, extração de dados e avaliação foram realizadas por dois revisores. Para avaliar a qualidade dos estudos utilizou-se as diretrizes do National Institutes of Health (NIH). De 132 estudos potencialmente elegíveis, 12 foram selecionados de acordo com os critérios de elegibilidade. Os resultados indicaram que pessoas com TE apresentam baixa sensibilidade visual quando comparados com indivíduos saudáveis, apesar de não apresentarem prejuízos na visão de cores. Apesar da heterogeneidade dos dados, observamos que existem prejuízos visuais em pessoas com TE e estes podem ser uma das principais características clínicas não-motoras.
Collapse
|
18
|
Gao C, Smith S, Lones M, Jamieson S, Alty J, Cosgrove J, Zhang P, Liu J, Chen Y, Du J, Cui S, Zhou H, Chen S. Objective assessment of bradykinesia in Parkinson's disease using evolutionary algorithms: clinical validation. Transl Neurodegener 2018; 7:18. [PMID: 30147869 PMCID: PMC6094893 DOI: 10.1186/s40035-018-0124-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 07/27/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND There is an urgent need for developing objective, effective and convenient measurements to help clinicians accurately identify bradykinesia. The purpose of this study is to evaluate the accuracy of an objective approach assessing bradykinesia in finger tapping (FT) that uses evolutionary algorithms (EAs) and explore whether it can be used to identify early stage Parkinson's disease (PD). METHODS One hundred and seven PD, 41 essential tremor (ET) patients and 49 normal controls (NC) were recruited. Participants performed a standard FT task with two electromagnetic tracking sensors attached to the thumb and index finger. Readings from the sensors were transmitted to a tablet computer and subsequently analyzed by using EAs. The output from the device (referred to as "PD-Monitor") scaled from - 1 to + 1 (where higher scores indicate greater severity of bradykinesia). Meanwhile, the bradykinesia was rated clinically using the Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) FT item. RESULTS With an increasing MDS-UPDRS FT score, the PD-Monitor score from the same hand side increased correspondingly. PD-Monitor score correlated well with MDS-UPDRS FT score (right side: r = 0.819, P = 0.000; left side: r = 0.783, P = 0.000). Moreover, PD-Monitor scores in 97 PD patients with MDS-UPDRS FT bradykinesia and each PD subgroup (FT bradykinesia scored from 1 to 3) were all higher than that in NC. Receiver operating characteristic (ROC) curves revealed that PD-Monitor FT scores could detect different severity of bradykinesia with high accuracy (≥89.7%) in the right dominant hand. Furthermore, PD-Monitor scores could discriminate early stage PD from NC, with area under the ROC curve greater than or equal to 0.899. Additionally, ET without bradykinesia could be differentiated from PD by PD-Monitor scores. A positive correlation of PD-Monitor scores with modified Hoehn and Yahr stage was found in the left hand sides. CONCLUSIONS Our study demonstrated that a simple to use device employing classifiers derived from EAs could not only be used to accurately measure different severity of bradykinesia in PD, but also had the potential to differentiate early stage PD from normality.
Collapse
Affiliation(s)
- Chao Gao
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Stephen Smith
- Department of Electronic Engineering, University of York, York, UK
| | - Michael Lones
- Department of Computer Science, Heriot-Watt University, Edinburgh, UK
| | - Stuart Jamieson
- Department of Neurology, Leeds General Infirmary, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jane Alty
- Department of Neurology, Leeds General Infirmary, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jeremy Cosgrove
- Department of Neurology, Leeds General Infirmary, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Pingchen Zhang
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jin Liu
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yimeng Chen
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Juanjuan Du
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shishuang Cui
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Haiyan Zhou
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shengdi Chen
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
19
|
García-Martín E, Ramos MI, Cornejo-García JA, Galván S, Perkins JR, Rodríguez-Santos L, Alonso-Navarro H, Jiménez-Jiménez FJ, Agúndez JAG. Missense Gamma-Aminobutyric Acid Receptor Polymorphisms Are Associated with Reaction Time, Motor Time, and Ethanol Effects in Vivo. Front Cell Neurosci 2018; 12:10. [PMID: 29445327 PMCID: PMC5797743 DOI: 10.3389/fncel.2018.00010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 01/08/2018] [Indexed: 01/15/2023] Open
Abstract
Background: The Gamma-aminobutyric acid type A receptor (GABA-A receptor) is affected by ethanol concentrations equivalent to those reached during social drinking. At these concentrations, ethanol usually causes impairment in reaction and motor times in most, but not all, individuals. Objectives: To study the effect of GABA-A receptor variability in motor and reaction times, and the effect of low ethanol doses. Methods: Two hundred and fifty healthy subjects received one single dose of 0.5 g/Kg ethanol per os. Reaction and motor times were determined before ethanol challenge (basal), and when participants reached peak ethanol concentrations. We analyzed all common missense polymorphisms described in the 19 genes coding for the GABA-A receptor subunits by using TaqMan probes. Results: The GABRA6 rs4454083 T/C polymorphisms were related to motor times, with individuals carrying the C/C genotype having faster motor times, both, at basal and at peak ethanol concentrations. The GABRA4 rs2229940 T/T genotype was associated to faster reaction times and with lower ethanol effects, determined as the difference between basal reaction time and reaction time at peak concentrations. All these associations remained significant after correction for multiple comparisons. No significant associations were observed for the common missense SNPs GABRB3 rs12910925, GABRG2 rs211035, GABRE rs1139916, GABRP rs1063310, GABRQ rs3810651, GABRR1 rs12200969 or rs1186902, GABRR2 rs282129, and GABRR3 rs832032. Conclusions: This study provides novel information supporting a role of missense GABA-A receptor polymorphisms in reaction time, motor time and effects of low ethanol doses in vivo.
Collapse
Affiliation(s)
- Elena García-Martín
- Department of Pharmacology, Universidad de Extremadura, Cáceres, Spain.,ARADyAL Network, Instituto de Salud Carlos III, Madrid, Spain
| | - María I Ramos
- Department of Psychiatry, Universidad de Extremadura, Badajoz, Spain
| | - José A Cornejo-García
- ARADyAL Network, Instituto de Salud Carlos III, Madrid, Spain.,Research Laboratory, Instituto de Investigación Biomédica de Málaga, Regional University Hospital of Malaga, UMA, Malaga, Spain
| | - Segismundo Galván
- Department of Pharmacology, Universidad de Extremadura, Cáceres, Spain
| | - James R Perkins
- ARADyAL Network, Instituto de Salud Carlos III, Madrid, Spain.,Research Laboratory, Instituto de Investigación Biomédica de Málaga, Regional University Hospital of Malaga, UMA, Malaga, Spain
| | | | | | | | - José A G Agúndez
- Department of Pharmacology, Universidad de Extremadura, Cáceres, Spain.,ARADyAL Network, Instituto de Salud Carlos III, Madrid, Spain
| |
Collapse
|
20
|
Characterization of graphomotor functions in individuals with Parkinson's disease and essential tremor. Behav Res Methods 2018; 49:913-922. [PMID: 27325167 DOI: 10.3758/s13428-016-0752-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this study, we explored the relationship between the clinical features and motor impairments related to the graphomotor function of individuals with Parkinson's disease (PD) and essential tremor (ET). We recruited 46 participants: 12 with PD, 13 with ET, and 21 controls. All participants were asked to perform six graphomotor tasks on a digitizer tablet: drawing straight lines, cursive-connected loops, discrete circles, and continuous circles, and making goal-aimed movements with a stylus in two different directions with three different accuracy constraints. The results showed that although participants with PD were able to draw straight lines slightly faster than controls, they produced cursive-connected loops much slower than controls. In addition, in contrast to controls and individuals with ET, PDs also drew the cursive loops progressively smaller. In the aiming task, we found that equivalent movements with high accuracy constraints were drawn slower by individuals with ET or PD than by controls. However, when performing the equivalent movements with moderate or low accuracy constraints, PDs performed similarly to controls. In contrast to the equivalent movements, PD and ET participants both performed nonequivalent movements slower than controls, no matter the demands arising from the accuracy constraints. The present study shows that simple graphic tasks can differentiate impairments in fine motor function resulting from ET and PD.
Collapse
|
21
|
Wójcik-Pędziwiatr M, Mirek E, Rudzińska-Bar M, Szczudlik A. Eye movements in essential tremor patients with parkinsonian and cerebellar signs. Neurol Neurochir Pol 2017; 51:299-303. [DOI: 10.1016/j.pjnns.2017.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 05/05/2017] [Indexed: 11/28/2022]
|
22
|
Lau CI, Lin CC, Chen HJ, Wang HC, Chen WH, Liang JA. Increased risk of essential tremor in migraine: A population-based retrospective cohort study. PLoS One 2017; 12:e0173586. [PMID: 28288163 PMCID: PMC5348003 DOI: 10.1371/journal.pone.0173586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 02/22/2017] [Indexed: 11/18/2022] Open
Abstract
Purpose To examine the long-term risk of essential tremor (ET) in migraine. Methods Using population-based administrative data from a subset of the National Health Insurance Research Database (NHIRD) of Taiwan, we identified 22,696 newly diagnosed migraineurs (mean age 44.5 years) and a matched migraine-free cohort of 90,784 individuals in the period 2000–2008. Multivariable Cox proportional hazards regression analysis was conducted for assessing the ET risk for the migraine cohort compared to the migraine-free cohort. Results After adjusting for covariates, the migraine cohort had a 1.83-fold increased risk (95% CI 1.50–2.23) of subsequent ET in comparison to the migraine-free cohort (8.97 vs. 4.81 per 10,000 person-years). In the subgroup analysis, patients with migraine were associated with higher risks of ET, regardless of gender, age or the existence of comorbidities. Conclusion Our findings demonstrated an association between migraine and ET, suggesting a possible shared pathophysiology underpinning both disorders.
Collapse
Affiliation(s)
- Chi-Ieong Lau
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,Division of Clinical Neurology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Institute of Cognitive Neuroscience, University College London, Queen Square, London, United Kingdom.,College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan
| | - Che-Chen Lin
- Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.,Healthcare Service Research Center (HSRC), Taichung Veterans General Hospital, Taichung, Taiwan
| | - Hsuan-Ju Chen
- Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.,College of Medicine, China Medical University, Taichung, Taiwan
| | - Han-Cheng Wang
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,College of Medicine, Taipei Medical University, Taipei, Taiwan.,College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wei-Hung Chen
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ji-An Liang
- Graduate Institute of Clinical Medical Science, School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan
| |
Collapse
|
23
|
Abstract
Essential tremor (ET) might be a family of diseases unified by the presence of kinetic tremor, but also showing etiological, pathological, and clinical heterogeneity. In this review, we will describe the most significant clinical evidence, which suggests that ET is linked to the cerebellum. Data for this review were identified by searching PUBMED (January 1966 to May 2015) crossing the terms "essential tremor" (ET) and "cerebellum," which yielded 201 entries, 11 of which included the term "cerebellum" in the article title. This was supplemented by articles in the author's files that pertained to this topic. The wide spectrum of clinical features of ET that suggest that it originates as a cerebellar or cerebellar outflow problem include the presence of intentional tremor, gait and balance abnormalities, subtle features of dysarthria, and oculomotor abnormalities, as well as deficits in eye-hand coordination, motor learning deficits, incoordination during spiral drawing task, abnormalities in motor timing and visual reaction time, impairment of social abilities, improvement in tremor after cerebellar stroke, efficacy of deep brain stimulation (which blocks cerebellar outflow), and cognitive dysfunction. It is unlikely, however, that cerebellar dysfunction, per se, fully explains ET-associated dementia, because the cognitive deficits that have been described in patients with cerebellar lesions are generally mild. Overall, a variety of clinical findings suggest that in at least a sizable proportion of patients with ET, there is an underlying abnormality of the cerebellum and/or its pathways.
Collapse
|
24
|
Robertson EE, Hall DA, McAsey AR, O'Keefe JA. Fragile X-associated tremor/ataxia syndrome: phenotypic comparisons with other movement disorders. Clin Neuropsychol 2016; 30:849-900. [PMID: 27414076 PMCID: PMC7336900 DOI: 10.1080/13854046.2016.1202239] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 06/12/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The purpose of this paper is to review the typical cognitive and motor impairments seen in fragile X-associated tremor/ataxia syndrome (FXTAS), essential tremor (ET), Parkinson disease (PD), spinocerebellar ataxias (SCAs), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP) in order to enhance diagnosis of FXTAS patients. METHODS We compared the cognitive and motor phenotypes of FXTAS with each of these other movement disorders. Relevant neuropathological and neuroimaging findings are also reviewed. Finally, we describe the differences in age of onset, disease severity, progression rates, and average lifespan in FXTAS compared to ET, PD, SCAs, MSA, and PSP. We conclude with a flow chart algorithm to guide the clinician in the differential diagnosis of FXTAS. RESULTS By comparing the cognitive and motor phenotypes of FXTAS with the phenotypes of ET, PD, SCAs, MSA, and PSP we have clarified potential symptom overlap while elucidating factors that make these disorders unique from one another. In summary, the clinician should consider a FXTAS diagnosis and testing for the Fragile X mental retardation 1 (FMR1) gene premutation if a patient over the age of 50 (1) presents with cerebellar ataxia and/or intention tremor with mild parkinsonism, (2) has the middle cerebellar peduncle (MCP) sign, global cerebellar and cerebral atrophy, and/or subcortical white matter lesions on MRI, or (3) has a family history of fragile X related disorders, intellectual disability, autism, premature ovarian failure and has neurological signs consistent with FXTAS. Peripheral neuropathy, executive function deficits, anxiety, or depression are supportive of the diagnosis. CONCLUSIONS Distinct profiles in the cognitive and motor domains between these movement disorders may guide practitioners in the differential diagnosis process and ultimately lead to better medical management of FXTAS patients.
Collapse
Affiliation(s)
- Erin E Robertson
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
| | - Deborah A Hall
- b Department of Neurological Sciences , Rush University , Chicago , IL , USA
| | - Andrew R McAsey
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
| | - Joan A O'Keefe
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
- b Department of Neurological Sciences , Rush University , Chicago , IL , USA
| |
Collapse
|
25
|
Rao AK, Louis ED. Timing control of gait: a study of essential tremor patients vs. age-matched controls. CEREBELLUM & ATAXIAS 2016; 3:5. [PMID: 26937284 PMCID: PMC4774137 DOI: 10.1186/s40673-016-0043-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 01/23/2016] [Indexed: 11/18/2022]
Abstract
Background Essential tremor (ET) is a common movement disorder characterized by kinetic, postural and intention tremors. Mounting evidence suggests an underlying dysfunction of the cerebellum or cerebellar system. While few recent studies report impairments in timing control of finger movements in ET, timing control of gait has not been examined to date. We compared timing control of gait in ET patients vs. controls, and further assessed the association of these timing impairments with tremor severity among the ET patients. One-hundred-fifty-five ET patients and 60 age-matched controls underwent a comprehensive neurological assessment and gait analysis, which included walking at a criterion step frequency (cadence) with a metronome (timing production) and walking at a criterion step frequency after the metronome was turned off (timing reproduction). Outcomes of interest for both conditions were timing accuracy (measured by cadence error) and timing precision (measured by cadence variability). We also assessed cadence and step time across conditions. Results Cadence was lower in ET patients than controls (p < 0.03), whereas step time was similar for ET patients and controls. Accuracy (cadence error) and precision (cadence variability) were not different in ET patients compared with controls. Cranial tremor score was significantly associated with cadence (timing production condition, p = 0.003 and timing reproduction condition, p = 0.0001) and cadence error (timing production condition, p = 0.01). Kinetic tremor and intention tremor scores were not associated with gait measures. Conclusions ET patients do not demonstrate impairments in timing control of gait as compared with matched controls. Prior work shows that patients with cerebellar dysfunction demonstrate selective impairments in timing of discrete movements (such as finger tapping) but not continuous movements (such as circle drawing). Taken together, these results support the hypothesis that the cerebellum may be important for timing control of discrete rather than continuous movements.
Collapse
Affiliation(s)
- Ashwini K Rao
- Department of Rehabilitation & Regenerative Medicine (Physical Therapy), College of Physicians and Surgeons, Columbia University, New York, NY USA ; G.H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY USA ; Neurological Institute, 8th Floor, 710 West 168th Street, New York, NY 10032 USA
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT USA ; Department of Chronic Disease Epidemiology, Yale School of Medicine, Yale University, New Haven, CT USA ; Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT USA
| |
Collapse
|
26
|
Vilas-Boas MDC, Cunha JPS. Movement Quantification in Neurological Diseases: Methods and Applications. IEEE Rev Biomed Eng 2016; 9:15-31. [PMID: 27008673 DOI: 10.1109/rbme.2016.2543683] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
27
|
The relationship between essential tremor and Parkinson's disease. Parkinsonism Relat Disord 2016; 22 Suppl 1:S162-5. [DOI: 10.1016/j.parkreldis.2015.09.032] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 09/13/2015] [Accepted: 09/15/2015] [Indexed: 11/18/2022]
|
28
|
Benito-León J, Louis ED, Romero JP, Hernández-Tamames JA, Manzanedo E, Álvarez-Linera J, Bermejo-Pareja F, Posada I, Rocon E. Altered Functional Connectivity in Essential Tremor: A Resting-State fMRI Study. Medicine (Baltimore) 2015; 94:e1936. [PMID: 26656325 PMCID: PMC5008470 DOI: 10.1097/md.0000000000001936] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Essential tremor (ET) has been associated with a spectrum of clinical features, with both motor and nonmotor elements, including cognitive deficits. We employed resting-state functional magnetic resonance imaging (fMRI) to assess whether brain networks that might be involved in the pathogenesis of nonmotor manifestations associated with ET are altered, and the relationship between abnormal connectivity and ET severity and neuropsychological function.Resting-state fMRI data in 23 ET patients (12 women and 11 men) and 22 healthy controls (HC) (12 women and 10 men) were analyzed using independent component analysis, in combination with a "dual-regression" technique, to identify the group differences of resting-state networks (RSNs) (default mode network [DMN] and executive, frontoparietal, sensorimotor, cerebellar, auditory/language, and visual networks). All participants underwent a neuropsychological and neuroimaging session, where resting-state data were collected.Relative to HC, ET patients showed increased connectivity in RSNs involved in cognitive processes (DMN and frontoparietal networks) and decreased connectivity in the cerebellum and visual networks. Changes in network integrity were associated not only with ET severity (DMN) and ET duration (DMN and left frontoparietal network), but also with cognitive ability. Moreover, in at least 3 networks (DMN and frontoparietal networks), increased connectivity was associated with worse performance on different cognitive domains (attention, executive function, visuospatial ability, verbal memory, visual memory, and language) and depressive symptoms. Further, in the visual network, decreased connectivity was associated with worse performance on visuospatial ability.ET was associated with abnormal brain connectivity in major RSNs that might be involved in both motor and nonmotor symptoms. Our findings underscore the importance of examining RSNs in this population as a biomarker of disease.
Collapse
Affiliation(s)
- Julián Benito-León
- From the Department of Neurology, University Hospital "12 de Octubre", Madrid (JB-L, FB-P, IP); Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) (JB-L, FB-P); Department of Medicine, Complutense University, Madrid, Spain (JB-L, FB-P, IP); Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA (EDL); Faculty of Biosanitary Sciences, Francisco de Vitoria University, Pozuelo de Alarcón (JPR); Neuroimaging Laboratory, Center for Biomedical Technology, Rey Juan Carlos University, Móstoles (JAH-T, EM); Department of Radiology, Hospital Ruber International, Madrid (JA-L); and Neural and Cognitive Engineering group, CAR, UPM-CSIC, CSIC, La Poveda - Arganda del Rey, Spain (ER)
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Pauletti C, Mannarelli D, De Lucia MC, Locuratolo N, Currà A, Missori P, Marinelli L, Fattapposta F. Selective attentional deficit in essential tremor: Evidence from the attention network test. Parkinsonism Relat Disord 2015; 21:1306-11. [PMID: 26365776 DOI: 10.1016/j.parkreldis.2015.08.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/08/2015] [Accepted: 08/30/2015] [Indexed: 01/18/2023]
Abstract
INTRODUCTION The traditional view of essential tremor (ET) as a monosymptomatic and benign disorder has been reconsidered after patients with ET have been shown to experience cognitive deficits that are also related to attention. The Attention Network Test (ANT) is a rapid, widely used test to measure the efficiency of three attentional networks, i.e. alerting, orienting and executive, by evaluating reaction times (RTs) in response to visual stimuli. The aim of this study was to investigate attentional functioning in ET patients by means of the ANT. METHODS 21 non-demented patients with ET and 21 age- and sex-matched healthy controls performed the ANT. RESULTS RT was significantly longer in ET patients than in controls (p < 0.001). Moreover, a significant difference in alerting and executive efficiency (p = 0.003 and p = 0.01 respectively) was found between groups, while the difference in the orienting efficiency only bordered on significance. CONCLUSION Our results point to a difficulty in the alerting and executive domains of attention in ET patients, probably owing to a dysfunction in the cerebello-thalamo-cortical loop. These selective attentional deficits are not related to clinical motor symptoms, contributing to shed further light on the clinical picture of ET.
Collapse
Affiliation(s)
- Caterina Pauletti
- Department of Neurology and Psychiatry, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| | - Daniela Mannarelli
- Department of Neurology and Psychiatry, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| | - Maria Caterina De Lucia
- Department of Neurology and Psychiatry, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| | - Nicoletta Locuratolo
- Department of Neurology and Psychiatry, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| | - Antonio Currà
- Department of Medical-Surgical Sciences and Biotechnologies, A. Fiorini Hospital, Sapienza University of Rome, Polo Pontino, Via Firenze, 04019, Terracina, LT, Italy.
| | - Paolo Missori
- Department of Neurology and Psychiatry, Neurosurgery, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| | - Lucio Marinelli
- Institute of Neurology, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), Largo Daneo 3, University of Genova, 16132, Genova, Italy.
| | - Francesco Fattapposta
- Department of Neurology and Psychiatry, Sapienza University of Rome, Viale dell'Università 30, 00185, Rome, Italy.
| |
Collapse
|
30
|
Londral A, Pinto S, de Carvalho M. Markers for upper limb dysfunction in Amyotrophic Lateral Sclerosis using analysis of typing activity. Clin Neurophysiol 2015; 127:925-931. [PMID: 26160275 DOI: 10.1016/j.clinph.2015.06.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 05/21/2015] [Accepted: 06/21/2015] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Assistive devices based on keyboard access support communication and control tools for patients with Amyotrophic Lateral Sclerosis (ALS). The aim of this work was to explore movement activity in the use of keyboards and identify markers for upper limb (UL) dysfunction. METHODS We present a longitudinal study including 19 ALS patients, followed for 2-20 months. Typing activity was recorded with an accelerometer placed on the posterior part of patients' index finger. Participants performed the same 10-word typing task (2-6 assessments). Time and acceleration during keystroke were the main outcomes of this study. Patients were compared with 20 healthy subjects and 6 patients with other neuromuscular disorders. RESULTS During disease progression, mean time in holding down a key increased and was longer than in control subjects. Acceleration at key press and key release decreased with progression of UL dysfunction. Delay between tapping and pressing down each key increased with UL dysfunction. CONCLUSIONS Delay in pressing and releasing keys are markers of UL dysfunction in ALS. The decrease in the acceleration of movements related to keystroke can contribute to monitor disease progression. SIGNIFICANCE Typing activity can be explored to access remotely and continuously to ALS progression by patients who use assistive communication devices.
Collapse
Affiliation(s)
- Ana Londral
- Translational Clinical Physiology Unit, Instituto de Medicina Molecular, Institute of Physiology - Faculty of Medicine, University of Lisbon, Portugal.
| | - Susana Pinto
- Translational Clinical Physiology Unit, Instituto de Medicina Molecular, Institute of Physiology - Faculty of Medicine, University of Lisbon, Portugal
| | - Mamede de Carvalho
- Translational Clinical Physiology Unit, Instituto de Medicina Molecular, Institute of Physiology - Faculty of Medicine, University of Lisbon, Portugal; Department of Neurosciences, Hospital de Santa Maria - CHLN, Lisbon, Portugal
| |
Collapse
|
31
|
News and controversies regarding essential tremor. Rev Neurol (Paris) 2015; 171:415-25. [DOI: 10.1016/j.neurol.2015.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/01/2015] [Accepted: 02/02/2015] [Indexed: 01/08/2023]
|
32
|
Hubel KA, Reed B, Yund EW, Herron TJ, Woods DL. Computerized measures of finger tapping: effects of hand dominance, age, and sex. Percept Mot Skills 2014; 116:929-52. [PMID: 24175464 DOI: 10.2466/25.29.pms.116.3.929-952] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Computerized measures of digit tapping rate were obtained over 3 successive, 10-sec. periods in the right and left index fingers, from a community sample of 1,519 participants (ages 18 to 65 years; 607 men, 912 women). Differences between the dominant and non-dominant hands were found for tapping rate, movement initiation, and button down times, and the decline in tapping rate over the successive, 10-sec. periods. Declines were found in tapping rate in older participants in association with increased intertap variability. Men had higher tapping rates than women in all age ranges. The computerized finger tapping test is an efficient and precise measure of tapping speed and kinetics of potential utility in research and clinical studies of motor performance.
Collapse
Affiliation(s)
- Kerry A Hubel
- Human Cognitive Neurophysiology Laboratory, VANCHCS, Martinez, CA 94553, USA
| | | | | | | | | |
Collapse
|
33
|
Schmouth JF, Dion PA, Rouleau GA. Genetics of essential tremor: From phenotype to genes, insights from both human and mouse studies. Prog Neurobiol 2014; 119-120:1-19. [DOI: 10.1016/j.pneurobio.2014.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/16/2014] [Accepted: 05/02/2014] [Indexed: 11/30/2022]
|
34
|
Benito-León J. Essential tremor: a neurodegenerative disease? TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2014; 4:252. [PMID: 25120943 PMCID: PMC4107287 DOI: 10.7916/d8765cg0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 06/29/2014] [Indexed: 12/01/2022]
Abstract
Background Essential tremor (ET) is one of the most common neurological disorders among adults, and is the most common of the many tremor disorders. It has classically been viewed as a benign monosymptomatic condition, yet over the past decade, a growing body of evidence indicates that ET is a progressive condition that is clinically heterogeneous, as it may be associated with a spectrum of clinical features, with both motor and non-motor elements. In this review, I will describe the most significant emerging milestones in research which, when taken together, suggest that ET is a neurodegenerative condition. Methods A PubMed search conducted in June 2014 crossing the terms “essential tremor” (ET) and “neurodegenerative” yielded 122 entries, 20 of which included the term “neurodegenerative” in the article title. This was supplemented by articles in the author's files that pertained to this topic. Results/Discussion There is an open and active dialogue in the medical community as to whether ET is a neurodegenerative disease, with considerable evidence in favor of this. Specifically, ET is a progressive disorder of aging associated with neuronal loss (reduction in Purkinje cells) as well as other post-mortem changes that occur in traditional neurodegenerative disorders. Along with this, advanced neuroimaging techniques are now demonstrating distinct structural changes, several of which are consistent with neuronal loss, in patients with ET. However, further longitudinal clinical and neuroimaging longitudinal studies to assess progression are required.
Collapse
Affiliation(s)
- Julián Benito-León
- Department of Neurology, University Hospital "12 de Octubre", Madrid, Spain ; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain ; Department of Medicine, Complutense University, Madrid, Spain
| |
Collapse
|
35
|
Martinez-Hernandez HR, Louis ED. Macrographia in essential tremor: a study of patients with and without rest tremor. Mov Disord 2014; 29:960-1. [PMID: 24757126 DOI: 10.1002/mds.25894] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 01/31/2014] [Accepted: 03/25/2014] [Indexed: 11/09/2022] Open
|
36
|
Hubel KA, Yund EW, Herron TJ, Woods DL. Computerized measures of finger tapping: reliability, malingering and traumatic brain injury. J Clin Exp Neuropsychol 2013; 35:745-58. [PMID: 23947782 DOI: 10.1080/13803395.2013.824070] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We analyzed computerized finger tapping metrics in four experiments. Experiment 1 showed tapping-rate differences associated with hand dominance, digits, sex, and fatigue that replicated those seen in a previous, large-scale community sample. Experiment 2 revealed test-retest correlations (r = .91) that exceeded those reported in previous tapping studies. Experiment 3 investigated subjects simulating symptoms of traumatic brain injury (TBI); 62% of malingering subjects produced abnormally slow tapping rates. A tapping-rate malingering index, based on rate-independent tapping patterns, provided confirmatory evidence of malingering in 48% of the subjects with abnormal tapping rates. Experiment 4 compared tapping in 24 patients with mild TBI (mTBI) and a matched control group; mTBI patients showed slowed tapping without evidence of malingering. Computerized finger tapping measures are reliable measures of motor speed, useful in detecting subjects performing with suboptimal effort, and are sensitive to motor abnormalities following mTBI.
Collapse
Affiliation(s)
- Kerry A Hubel
- a Human Cognitive Neurophysiology Laboratory , Martinez Clinic , Martinez , CA , USA
| | | | | | | |
Collapse
|
37
|
Hubel KA, Reed B, Yund EW, Herron TJ, Woods DL. COMPUTERIZED MEASURES OF FINGER TAPPING: EFFECTS OF HAND DOMINANCE, AGE, AND SEX1,2. Percept Mot Skills 2013. [DOI: 10.2466/25.29.pms.116.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
38
|
Ozen Barut B, Gunal DI, Turkmen C, Mollahasanoğlu A, Ankaralı H. Clinical and cognitive profiles of patients with both Parkinson's disease and essential tremor. Acta Neurol Belg 2013; 113:117-25. [PMID: 22926528 DOI: 10.1007/s13760-012-0124-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 07/31/2012] [Indexed: 11/24/2022]
Abstract
Although Parkinson's disease (PD) and essential tremor (ET) are distinct clinical disorders, their coexistence can sometimes cause diagnostic problems. In this study, we conducted detailed investigations of patients with both ET and PD (ET-PD) and compared their clinical and cognitive profiles with those of patients with only ET or only PD. This study examined three groups of patients: the first group had ET-PD concomitantly (n = 9); the second group had only ET (n = 9); the third group had only PD (n = 10). The groups were compared in terms of demographic characteristics, clinical features, and cognitive functions. With the exception of positive family histories, which were more common in ET-PD than in PD patients, we found no differences among the groups with respect to demographic characteristics (p = 0.044). PD-only patients had more akinetic-rigid type Parkinsonism (p = 0.016), and their levodopa response was better than that of ET-PD patients (p = 0.017). Patients with ET-PD obtained significantly lower scores than those with pure ET on several cognitive tests, suggesting a prominent frontal-type cognitive dysfunction. In conclusion ET-PD patients differed from PD patients, showing more frequent familial tremor histories and lower levodopa responsiveness. This patient population also demonstrated more severe cognitive impairments than pure-ET patients. This result suggests that ET-PD patients are a subset of ET patients with more widespread neurodegeneration, which may indicate the presence of a syndrome that includes overlap between ET and PD.
Collapse
Affiliation(s)
- Banu Ozen Barut
- Faculty of Medicine, Department of Neurology, Bülent Ecevit University, Zonguldak, Turkey.
| | | | | | | | | |
Collapse
|
39
|
Norman KE, Héroux ME. Measures of fine motor skills in people with tremor disorders: appraisal and interpretation. Front Neurol 2013; 4:50. [PMID: 23717299 PMCID: PMC3650669 DOI: 10.3389/fneur.2013.00050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/24/2013] [Indexed: 12/04/2022] Open
Abstract
People with Parkinson's disease, essential tremor, or other movement disorders involving tremor have changes in fine motor skills that are among the hallmarks of these diseases. Numerous measurement tools have been created and other methods devised to measure such changes in fine motor skills. Measurement tools may focus on specific features - e.g., motor skills or dexterity, slowness in movement execution associated with parkinsonian bradykinesia, or magnitude of tremor. Less obviously, some tools may be better suited than others for specific goals such as detecting subtle dysfunction early in disease, revealing aspects of brain function affected by disease, or tracking changes expected from treatment or disease progression. The purpose of this review is to describe and appraise selected measurement tools of fine motor skills appropriate for people with tremor disorders. In this context, we consider the tools' content - i.e., what movement features they focus on. In addition, we consider how measurement tools of fine motor skills relate to measures of a person's disease state or a person's function. These considerations affect how one should select and interpret the results of these tools in laboratory and clinical contexts.
Collapse
Affiliation(s)
- Kathleen E. Norman
- School of Rehabilitation Therapy, Queen’s UniversityKingston, ON, Canada
- Centre for Neuroscience Studies, Queen’s UniversityKingston, ON, Canada
| | | |
Collapse
|
40
|
Thenganatt MA, Louis ED. Distinguishing essential tremor from Parkinson's disease: bedside tests and laboratory evaluations. Expert Rev Neurother 2013; 12:687-96. [PMID: 22650171 DOI: 10.1586/ern.12.49] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Distinguishing essential tremor from Parkinson's disease can be challenging, both in the early stages of these diseases and as these diseases progress. Various tremor types (rest, postural, kinetic and intention) may be seen in both essential tremor and Parkinson's disease. Furthermore, with time, the two diseases may coexist within a single patient. Detailed clinical examination with attention to specific features of tremor (frequency, amplitude, pattern and distribution) and associated neurological findings may help distinguish patients with the two diseases. Laboratory testing may provide information that further aids in differentiating the two diseases. These tests include accelerometry and surface electromyography, spiral analysis, dopamine transporter imaging, olfactory testing and, eventually, postmortem histopathology. These tests have limitations and their diagnostic utility requires additional study.
Collapse
Affiliation(s)
- Mary Ann Thenganatt
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | | |
Collapse
|
41
|
Bermejo-Pareja F, Puertas-Martín V. Cognitive features of essential tremor: a review of the clinical aspects and possible mechanistic underpinnings. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2012; 2. [PMID: 23440004 PMCID: PMC3572680 DOI: 10.7916/d89w0d7w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 05/08/2012] [Indexed: 01/10/2023]
Abstract
The classical concept of essential tremor (ET) as a monosymptomatic tremorogenic disorder has been questioned in the last decade as new evidence has been described. Clinical, neuroimaging, and pathological studies have described a probable structural basis (mainly in cerebellum) and evidence that ET is associated with subtle clinical cerebellar deficits and several non-motor clinical manifestations, such as cognitive and mood disorders. We performed literature searches in Medline, ISI Web of Knowledge, and PsycInfo databases. The aim of this review is to describe cognitive deficits associated with ET. First, we present a brief history of ET cognitive disorders presented. Second, we describe several clinical cross-sectional series demonstrating that ET is associated with mild cognitive deficits of attention, executive functions, several types of memory (working memory, immediate, short term, delayed, and possibly others) and, mood disorders (depression). Recent neuroimaging studies favor a cerebellar basis for these cognitive deficits. Population-based surveys confirm that mild cognitive dysfunction is not limited to severe ET cases, the entire ET group, including mild and undiagnosed cases, can be affected. Cohort studies indicated that ET cognitive deficits could be progressive and that ET patients had an increased risk of dementia. The mood and cognitive deficits in ET are in agreement with cognitive affective cerebellar syndrome described in patients with cerebellar disorders. New evidence, mainly from functional (neuroimaging) and prospective clinical studies would further bolster recent descriptions of ET clinical manifestations.
Collapse
Affiliation(s)
- Félix Bermejo-Pareja
- Head of the Neurology Department, University Hospital "12 de Octubre", Madrid, Spain ; Biomedical Research Network on Neurodegenerative Disorders (CIBERNED), Carlos III National Research Institute, Madrid, Spain ; Department of Biomedical Sciences (ANECA), Complutense University of Madrid, Spain
| | | |
Collapse
|
42
|
Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Agúndez JAG. The relationship between Parkinson's disease and essential tremor: review of clinical, epidemiologic, genetic, neuroimaging and neuropathological data, and data on the presence of cardinal signs of parkinsonism in essential tremor. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2012; 2. [PMID: 23439992 PMCID: PMC3572635 DOI: 10.7916/d8fn14z6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 01/18/2012] [Indexed: 12/01/2022]
Abstract
BACKGROUND The possible relationship between essential tremor (ET) and Parkinson's disease (PD) has been controversial since the first description of PD. However, there is increasing evidence suggesting an overlap between these two disorders. The aim of this review is to examine the relationship between PD and ET, focusing on clinical, epidemiologic, genetic, neuroimaging, and neuropathological data, and the presence of cardinal parkinsonism symptoms in ET. METHODS We conducted a PubMed search for articles published between 1966 and November 2011 regarding the relationship between ET and PD and the presence of postural tremor in PD patients; the presence of rest tremor, rigidity, and slowed movements in ET patients is reviewed. RESULTS Clinical series, follow-up studies of ET patients, and case-control and genetic epidemiological studies indicate that ET is associated with increased risk for PD. Some neuroimaging studies and neuropathological reports suggest an association between the two diseases. ET patients show high prevalence of rest tremor, and at least seven studies described slowed movements (possibly related to cerebellar dysfunction and/or bradykinesia) in patients with ET. DISCUSSION There is reasonable epidemiological and clinical evidence to support a link between ET and PD, although it is not clear what factors predict ET patient risk for developing PD or, more rarely, of PD patients developing ET. Future multicentric and multidisciplinary studies including epidemiological, clinical, neuroimaging, genetic, and neuropathological assessments are required to understand these associations.
Collapse
|
43
|
Abstract
Motor speed is an important indicator and predictor of both cognitive and physical function. One common assessment of motor speed is the finger-tapping test (FTT), which is typically administered as part of a neurological or neuropsychological assessment. However, the FTT suffers from several limitations, including infrequent in-person administration, the need for a trained assessor and dedicated equipment, and potential short-term sensory-motor fatigue. In this article, we propose an alternative method of measuring motor speed, with face validity to the FTT, that addresses these limitations by measuring the interkeystroke intervals (IKI) of familiar and repeated login data collected in the home during a subject's regular computer use. We show significant correlations between the mean tapping speeds from the FTT and the median IKIs of the nondominant (r = .77) and dominant (r = .70) hands, respectively, in an elderly cohort of subjects living independently. Finally, we discuss how the proposed method for measuring motor speed fits well into the framework of unobtrusive and continuous in-home assessment.
Collapse
|
44
|
Gerbin M, Viner AS, Louis ED. Sleep in essential tremor: a comparison with normal controls and Parkinson's disease patients. Parkinsonism Relat Disord 2011; 18:279-84. [PMID: 22130149 DOI: 10.1016/j.parkreldis.2011.11.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 10/06/2011] [Accepted: 11/04/2011] [Indexed: 11/16/2022]
Abstract
BACKGROUND Recent studies have shed light on non-motor features of ET, such as depressive symptoms and cognitive changes, which might be attributed to pathophysiological changes in the brains of ET patients. Given these brain changes, we explored sleep abnormalities in ET patients. METHODS Sleep was assessed using the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) in 120 ET cases, 120 normal controls, and 40 PD cases. RESULTS The mean±SD (median) ESS score increased from normal controls (5.7±3.7 (5.0)), to ET cases (6.8±4.6 (6.0)), to PD cases (7.8±4.9 (7.0)), test for trend p=0.03. An ESS score >10 (an indicator of greater than normal levels of daytime sleepiness) was observed in 11 (9.2%) normal controls, compared to 27 (22.5%) ET cases and 10 (25.0%) PD cases (p=0.008 when comparing all three groups, and p=0.005 when comparing ET to normal controls). The global PSQI score was 7.8±2.8 (7.5) in controls, 8.0±3.3 (8.0) in ET cases, and 9.9±3.9 (10.0) in PD cases. The ET case-control difference was not significant (p=0.8), yet in a test for trend, PD cases had the highest PSQI score (most daytime sleepiness), followed by ET (intermediate), and lowest scores in controls (p=0.02). CONCLUSIONS Some sleep scores in ET were intermediate between those of PD cases and normal controls, suggesting that a mild form of sleep dysregulation could be present in ET.
Collapse
Affiliation(s)
- Marina Gerbin
- GH Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | | | | |
Collapse
|
45
|
Schapira AHV, Hillbom M. Publishing changes and information delivery in the clinical neurosciences. Eur J Neurol 2011. [DOI: 10.1111/j.1468-1331.2011.03594.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
46
|
Fekete R, Jankovic J. Revisiting the relationship between essential tremor and Parkinson's disease. Mov Disord 2011; 26:391-8. [PMID: 21462256 DOI: 10.1002/mds.23512] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND The relationship between essential tremor and Parkinson's disease has been a subject of reviews and debates for long time, but there is now growing evidence that the two common movement disorders are pathogenically related, at least in some patient populations. METHODS PubMed as well as authors' own files were searched for relevant keywords regarding overlap between the disorders in clinical features as well as on epidemiologic, genetic, imaging, and pathological studies. RESULTS New findings in each of these categories are critically reviewed and placed in the context of previously published data. DISCUSSION Although we believe that there is compelling evidence for the notion that some patients with "pure" ET evolve into PD, the biologic nature of the association is not well understood. Furthermore, it is not clear what factors predict which ET patients later develop PD and whether patients with PD are more likely to develop ET. Further epidemiologic, clinical, genetic, imaging, and pathological studies are needed to better understand this mixed, ET-PD phenotype.
Collapse
Affiliation(s)
- R Fekete
- Parkinson's Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, Texas 77030, USA
| | | |
Collapse
|
47
|
|
48
|
Askari S, Zhang M, Won DS. An EMG-based system for continuous monitoring of clinical efficacy of Parkinson's disease treatments. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2010:98-101. [PMID: 21095645 DOI: 10.1109/iembs.2010.5626133] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Current methods for assessing the efficacy of treatments for Parkinson's disease (PD) rely on physician rated scores. These methods pose three major shortcomings: 1) the subjectivity of the assessments, 2) the lack of precision on the rating scale (6 discrete levels), and 3) the inability to assess symptoms except under very specific conditions and/or for very specific tasks. To address these shortcomings, a portable system was developed to continuously monitor Parkinsonian symptoms with quantitative measures based on electrical signals from muscle activity (EMG). Here, we present the system design and the implementation of methods for system validation. This system was designed to provide continuous measures of tremor, rigidity, and bradykinesia which are related to the neurophysiological source without the need for multiple bulky experimental apparatuses, thus allowing more precise, quantitative indicators of the symptoms which can be measured during practical daily living tasks. This measurement system has the potential to improve the diagnosis of PD as well as the evaluation of PD treatments, which is an important step in the path to improving PD treatments.
Collapse
Affiliation(s)
- Sina Askari
- Department of Electrical Engineering, California State University Los Angeles, CA 90032, USA.
| | | | | |
Collapse
|
49
|
Jiménez-Jiménez FJ, Calleja M, Alonso-Navarro H, Rubio L, Navacerrada F, Pilo-de-la-Fuente B, Plaza-Nieto JF, Arroyo-Solera M, García-Ruiz PJ, García-Martín E, Agúndez JA. Influence of age and gender in motor performance in healthy subjects. J Neurol Sci 2011; 302:72-80. [DOI: 10.1016/j.jns.2010.11.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 11/20/2010] [Accepted: 11/22/2010] [Indexed: 11/28/2022]
|
50
|
Lorenzo-Betancor O, Samaranch L, García-Martín E, Cervantes S, Agúndez JA, Jiménez-Jiménez FJ, Alonso-Navarro H, Luengo A, Coria F, Lorenzo E, Irigoyen J, Pastor P. LINGO1
gene analysis in Parkinson's disease phenotypes. Mov Disord 2011; 26:722-7. [DOI: 10.1002/mds.23452] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 08/04/2010] [Accepted: 09/07/2010] [Indexed: 11/09/2022] Open
|