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Fajardo J, Melo LFD. Towards a Modular Pathological Tremor Simulation System Based on the Stewart Platform. SENSORS (BASEL, SWITZERLAND) 2023; 23:9020. [PMID: 38005408 PMCID: PMC10674838 DOI: 10.3390/s23229020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/25/2023] [Accepted: 10/25/2023] [Indexed: 11/26/2023]
Abstract
Wearable technologies have aided in reducing pathological tremor symptoms through non-intrusive solutions that aim to identify patterns in involuntary movements and suppress them using actuators positioned at specific joints. However, during the development of these devices, tests were primarily conducted on patients due to the difficulty of faithfully simulating tremors using simulation equipment. Based on studies characterizing tremors in Parkinson's disease, the development of a robotic manipulator based on the Stewart platform was initiated, with the goal of satisfactorily simulating resting tremor movements in the hands. In this work, a simulator was implemented in a computational environment using the multibody dynamics method. The platform structure was designed in a virtual environment using SOLIDWORKS® v2017 software and later exported to Matlab® R17a software using the Simulink environment and Simscape multibody library. The workspace was evaluated, and the Kalman filter was used to merge acceleration and angular velocity data and convert them into data related to the inclination and rotation of real patients' wrists, which were subsequently executed in the simulator. The results show a high correlation and low dispersion between real and simulated signals, demonstrating that the simulated mechanism has the capacity to represent Parkinson's disease resting tremors in all wrist movements. The system could contribute to conducting tremor tests in suppression devices without the need for the presence of the patient and aid in comparing suppression techniques, benefiting the development of new wearable devices.
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Affiliation(s)
- Jair Fajardo
- Federal Institute of Paraná, Assis Chateaubriand Campus, Assis Chateaubriand 85935-000, Brazil
| | - Leonimer Flávio de Melo
- Department of Electrical Engineering, State University of Londrina, Londrina 86057-970, Brazil
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Inoue M, Morihata H, Matoba S, Shibasaki H. A case of position dependent tremor. Rinsho Shinkeigaku 2021; 61:762-764. [PMID: 34657924 DOI: 10.5692/clinicalneurol.cn-001642] [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: 11/05/2022]
Abstract
A 79-year-old woman presented 3 years' history of hand shaking while drinking a cup of tea. The tremor was seen bilaterally, more predominantly on the left, and it also appeared when reading a book or writing. It was also induced by flexing the elbow to about 90 degrees or more without any specific task. Although there was no family history, the tremor in the present case was clinically diagnosed as essential tremor, because there were no other movement abnormalities, and other causes of tremor were excluded by laboratory tests. The tremor was dependent on the position of the involved extremity regardless of the kind of tasks. Position-specific tremor is discussed in relation to postural tremor.
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Affiliation(s)
- Manabu Inoue
- Department of Neurology, Osaka Saiseikai Nakatsu Hospital
| | | | - Shun Matoba
- Department of Neurology, Osaka City General Hospital
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Emamikhah M, Aghavali S, Moghadas F, Munhoz RP, Lang AE, Alavi A, Rohani M. Spinocerebellar Ataxia 40: Another Etiology Underlying Essential Tremor Syndrome. Mov Disord Clin Pract 2021; 8:944-946. [PMID: 34405102 DOI: 10.1002/mdc3.13251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 11/09/2022] Open
Affiliation(s)
- Maziar Emamikhah
- Department of Neurology Rasool-e Akram Hospital, Iran University of Medical Sciences Tehran Iran
| | - Sharmin Aghavali
- Department of Neurology Rasool-e Akram Hospital, Iran University of Medical Sciences Tehran Iran
| | - Fatemeh Moghadas
- Department of Neurology Rasool-e Akram Hospital, Iran University of Medical Sciences Tehran Iran
| | - Renato P Munhoz
- The Edmond J. Safra Program in Parkinson's Disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology University of Toronto Toronto Ontario Canada.,Krembil Brain Institute Toronto Ontario Canada
| | - Anthony E Lang
- The Edmond J. Safra Program in Parkinson's Disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology University of Toronto Toronto Ontario Canada.,Krembil Brain Institute Toronto Ontario Canada
| | - Afagh Alavi
- Genetics Research Center University of Social Welfare and Rehabilitation Sciences Tehran Iran
| | - Mohammad Rohani
- Department of Neurology Rasool-e Akram Hospital, Iran University of Medical Sciences Tehran Iran.,Skull Base Research Center, Five Senses Health Institute Iran University of Medical Sciences Tehran Iran
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Torrecillas V, Dwenger K, Barkmeier‐Kraemer JM. Classification of vocal tremor using updated consensus-based tremor classification criteria. Laryngoscope Investig Otolaryngol 2021; 6:261-276. [PMID: 33869758 PMCID: PMC8035951 DOI: 10.1002/lio2.544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES This study characterized the clinical phenotypes of individuals with vocal tremor (VT) using tremor classification criteria published by the International Parkinson and Movement Disorder Society (IPMDS) including laryngeal features from the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS). METHODS VT phenotypic descriptors were extracted from participant medical records from 2017 to 2019. Clinical phenotype descriptors included the: (a) chief complaint and discipline for the first appointment, (b) demographics, (c) tremor body distribution, condition, frequency, and progression, (d) exacerbating/alleviating factors, (e) treatment approaches, and (g) neurologic comorbidities. Descriptive statistics were conducted. RESULTS Of 179 meeting inclusion criteria, 2/3 were female; tremor onset affected voice (43%) or extremity (32%) and 2/3 were documented with tremor duration of 3 years or more. Those with primary VT first saw otolaryngology or speech language pathology (59%), whereas those with primary extremity/head tremor first saw neurology (36%). Documentation commonly omitted tremor clinical features such as (a) observed conditions of tremor (64%), (b) laryngeal features (64%), and (c) tremor frequency (92%). Thus, VT classification was based on comorbidity in 49% of patients (ie, essential tremor (48%), dystonia (72%), and Parkinson's disease (100%)) and 32% had inadequate documentation to classify. CONCLUSION The majority of individuals with VT were unable to be classified based on documented clinical features highlighting the need for consistent multidisciplinary assessment of tremor affecting speech structures. The primary site of tremor determined the first discipline seen. Most commonly classified VT categories included essential tremor (47%), dystonia (28%), Parkinsonism (7%), and isolated VT (19%). LEVEL OF EVIDENCE 4.
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Affiliation(s)
- Vanessa Torrecillas
- Division of Otolaryngology – Head and Neck SurgeryUniversity of UtahSalt Lake CityUtahUSA
| | - Kaitlyn Dwenger
- Division of Otolaryngology – Head and Neck SurgeryUniversity of UtahSalt Lake CityUtahUSA
- Department of Communication Sciences and DisordersUniversity of UtahSalt Lake CityUTUSA
| | - Julie M. Barkmeier‐Kraemer
- Division of Otolaryngology – Head and Neck SurgeryUniversity of UtahSalt Lake CityUtahUSA
- Department of Communication Sciences and DisordersUniversity of UtahSalt Lake CityUTUSA
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Novel Botulinum Toxin Injection Protocols for Parkinson Tremor and Essential Tremor - the Yale Technique and Sensor-Based Kinematics Procedure for Safe and Effective Treatment. Tremor Other Hyperkinet Mov (N Y) 2020; 10:61. [PMID: 33442486 PMCID: PMC7774361 DOI: 10.5334/tohm.582] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background: Hand tremor associated with Parkinson disease (PD) and essential tremor (ET) can often become challenging to treat in clinical practice. Local injections of botulinum toxin-A (BoNT-A) for hand tremor is an evolving field with newer injection techniques being utilized in clinical studies. The utility of BoNT-A therapy for ET and PD-tremor however, has been questioned based on the high incidence of finger and hand weakness after treatment. Method: The study includes detailed analysis of the techniques utilized in BoNT injection in ET and PD tremor. Results: There were 4 high-quality investigations which consisted of Class I or II double-blind placebo-controlled trials and one medium-quality study that was a prospective, open label, class III investigation. Discussion: This paper discusses two recently developed technology-based injection methods for BoNT-A therapy of ET and PD tremor, which includes comprehensive EMG screening of forearm and arm muscles with selective injections (Yale method) and the whole arm kinematic tremor assessment developed by Jog et al. In recent years, controlled, blinded studies of these two methods have shown significant post-injection reduction of finger, hand and whole limb tremor compared to the previously published controlled clinical trials not using these methodologies.
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Abstract
Essential tremor is one of the most common tremor syndromes. According to the recent tremor classification, tremor as a symptom is defined as an involuntary, rhythmic, oscillatory movement of a body part and is classified along two axes: axis 1-defining syndromes based on the clinical features such as historical features, tremor characteristics, associated signs, and laboratory tests; and axis 2-classifying the etiology (Bhatia et al., Mov Disord 33:75-87, 2018). The management of this condition has two major approaches. The first is to exclude treatable etiologies, as particularly during the onset of this condition the presentation of a variety of etiologies can be with monosymptomatic tremor. Once the few etiologies with causal treatments are excluded, all further treatment is symptomatic. Shared decision-making with enabling the patient to knowledgeably choose treatment options is needed to customize the management. Mild to moderate tremor severity can sometimes be controlled with occupational treatment, speech therapy of psychotherapy, or adaptation of coping strategy. First-line pharmacological treatments include symptomatic treatment with propranolol, primidone, and topiramate. Botulinum toxin is for selected cases. Invasive treatments for essential tremor should be considered for severe tremors. They are generally accepted as the most powerful interventions and provide not only improvement of tremor but also a significant improvement of life quality. The current standard is deep brain stimulation (DBS) of the thalamic and subthalamic region. Focused ultrasound thalamotomy is a new therapy attracting increasing interest. Radiofrequency lesioning is only rarely done if DBS or focused ultrasound is not possible. Radiosurgery is not well established. We present our treatment algorithm.
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Affiliation(s)
- Franziska Hopfner
- Department of Neurology, UKSH, Christian-Albrechts-University Kiel, Rosalind-Fraenklinstr. 10, 24105, Kiel, Germany
- Department of Neurology, Hannover Medical School, Hannover, Germany
| | - Günther Deuschl
- Department of Neurology, UKSH, Christian-Albrechts-University Kiel, Rosalind-Fraenklinstr. 10, 24105, Kiel, Germany.
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Amlang CJ, Trujillo Diaz D, Louis ED. Essential Tremor as a "Waste Basket" Diagnosis: Diagnosing Essential Tremor Remains a Challenge. Front Neurol 2020; 11:172. [PMID: 32269548 PMCID: PMC7109309 DOI: 10.3389/fneur.2020.00172] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/24/2020] [Indexed: 11/29/2022] Open
Abstract
Introduction: The diagnosis of essential tremor (ET) remains a clinical one, and diagnostic errors are common. We aimed to (1) determine precisely how frequently ET diagnoses are misapplied (i.e., what percentage of patients who have been assigned an “ET” diagnosis actually have another movement disorder), (2) determine which other movement disorders are most often misclassified as “ET,” and (3) examine the clinical features that were most associated with diagnostic errors. Methods: One hundred four consecutive patients were included who met the following criteria: (1) initial outpatient evaluation by one of the authors (EDL) between January 2015 and December 2019 and (2) pre-evaluation diagnosis of ET. Data on an extensive number of clinical features were extracted from the electronic medical record. Results: Forty-seven (45.2%) patients received a post-evaluation diagnosis of ET, 29 (27.9%) of dystonia, and 28 (26.9%) of other diagnoses including Parkinson's disease (PD) [6 (5.8%)]. Factors associated with an alternative post-evaluation diagnosis other than ET were pre-evaluation diagnosis made by a non-neurologist, shorter tremor duration, irregular tremor, abnormal limb postures, among others. Discussion: Diagnosing ET remains a challenge, with the diagnosis being over-applied and being used as a “waste basket.” More than one-half of the patients who were referred to our clinic with an intake diagnosis of ET were given an alternative post-evaluation diagnosis. While PD was reported to be the most frequently missed diagnosis in a past study, dystonia was most commonly missed in our study. Several clinical features can help to differentiate ET from other tremor disorders.
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Affiliation(s)
- Christian J Amlang
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Daniel Trujillo Diaz
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, United States
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States.,Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, United States.,Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, United States
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Zhang M, Li W, Hu L, Chen L, Yang L, Zhang T, Shen H, Peng Y, Gao S, Chen Z, Wang T, Zhao Z. Oral propranolol for treatment of the subgroups of essential tremor: a systematic review and meta-analysis protocol. BMJ Open 2020; 10:e032096. [PMID: 31948986 PMCID: PMC7044890 DOI: 10.1136/bmjopen-2019-032096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 11/21/2019] [Accepted: 12/04/2019] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Essential tremor (ET), a tremor disorder, is one of the most common movement disorders. Only oral drugs (propranolol, primidone, topiramate, etc)are still the first-line treatment recommended by the Food and Drug Administration. Propranolol is thought to potentially reduce upper limb action tremor. However, it has a poor effect on axial tremor symptoms, such as essential head tremor and voice tremor. Studies have shown that tremor severity develops over time, possibly producing other clinical tremors and neurological soft signs (such as memory loss, gait abnormalities, balance disorders, etc), which further increases the difficulty of treating tremors. However, some recent studies provide emerging evidence for oral propranolol on subgroups of ET, which is based on the anatomical distribution of ET (lower extremities, head, sound, tongue, etc). This systematic review aims to synthesise these new data to improve the efficacy of propranolol in ET subgroups. METHODS AND ANALYSIS We will search for randomised controlled trials from the PubMed, MEDLINE, EMBASE, Cochrane Library, UptoDate and PEDro databases from inception to June 2019. All data will be extracted independently by two reviewers and compared at the end of the review. The two reviewers will screen the study quality, and the Cochrane Collaboration's tool in Review Manager (RevMan) V.5.3.3 will be used to evaluate risk of bias. Our primary outcome will be the functional disability component related to tremors, as measured by the Fahn-Tolosa-Marin Tremor Rating Scale subscales B and C. Secondary outcomes will include severity of tremors and quality of life. Narrative and meta-analytical syntheses are planned. ETHICS AND DISSEMINATION Published aggregated data will be used in this review analysis and therefore no ethical approval is required. The results will be published in peer-reviewed journals, and proliferation activities will include diverse social stakeholders, non-academic groups and patients. PROSPERO REGISTRATION NUMBER CRD42018112580.
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Affiliation(s)
- Manyu Zhang
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Wei Li
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Lan Hu
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Li Chen
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Liu Yang
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Tian Zhang
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Hui Shen
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Yanan Peng
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Shijun Gao
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Zhibin Chen
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Tan Wang
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
| | - Zhenqiang Zhao
- Department of Neurology, First Affiliated Hospital, Hainan Medical University, Haikou, Hainan, China
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Schaefer SM, Hallett M, Karp BP, DiCapua DB, Tinaz S. Positional Tremor and its Treatment. Mov Disord Clin Pract 2017; 4:768-771. [PMID: 29057292 DOI: 10.1002/mdc3.12498] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Positional tremors arise when a patient's tremor is brought on during specific positioning of the involved body part. They can be distinguished from postural tremor, wherein a patient's tremor is elicited in any posture, and from task-specific tremor, wherein a patient's tremor occurs only during a certain task. CASES We describe two cases of positional tremor that are markedly improved with botulinum toxin injection. DISCUSSION The term "positional" is a valuable descriptor for tremors. In patients with positional tremor, botulinum toxin may be beneficial for treatment. Lidocaine injection provides a transient way to test for the appropriateness of botulinum toxin injection in these patients.
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Affiliation(s)
- Sara M Schaefer
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Barbara P Karp
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Daniel B DiCapua
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Sule Tinaz
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
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Louis ED, Badejo FM, Cristal AD, Meyers J, Hernandez N, Chen KP, Naranjo KV, Park J, Clark LN. Early Head Tremor in Essential Tremor: A Case Series and Commentary. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2017; 7:453. [PMID: 28373926 PMCID: PMC5374515 DOI: 10.7916/d8kw5mrg] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/07/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND Classically, the onset of head tremor in essential tremor (ET) patients follows that of hand tremor, such that there is a somatotopic spread of involved areas. Here we present a series of seven self-reportedly "unaffected" relatives of ET cases. These seven were clinically asymptomatic and had normal levels of arm tremor on examination, yet each evidenced a transient head wobble on examination. We estimate the prevalence of this phenotype within the two studies from which cases were ascertained. METHODS ET cases and their self-reportedly affected and unaffected relatives, enrolled in two family studies, underwent a medical history and videotaped neurological examination. RESULTS In seven self-reportedly "unaffected" relatives, a transient and subtle head wobble was seen, always during sustained phonation, speech, or reading aloud. Total tremor score (a measure of arm tremor) ranged from 5 to 12 (i.e., mild tremor within the range of normal). The prevalence of this phenotype of early head tremor was 3.7% in one study and 23.1% in the other. DISCUSSION We present a series of seven individuals who had early head tremor in an evolving transition state from normal to ET. These cases raise a number of broad clinical, phenotypic, and pathophysiological issues about ET.
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Affiliation(s)
- Elan D Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA; Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, CT, USA; Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, New Haven, CT, USA
| | - Funmi M Badejo
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Ashley D Cristal
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - James Meyers
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Nora Hernandez
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Karen P Chen
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Kelly V Naranjo
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Jemin Park
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Lorraine N Clark
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
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Jwair S, Coulon P, Ruigrok TJH. Disynaptic Subthalamic Input to the Posterior Cerebellum in Rat. Front Neuroanat 2017; 11:13. [PMID: 28293179 PMCID: PMC5329055 DOI: 10.3389/fnana.2017.00013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/17/2017] [Indexed: 12/31/2022] Open
Abstract
In the last decade, the interplay between basal ganglia and cerebellar functions has been increasingly advocated to explain their joint operation in both normal and pathological conditions. Yet, insight into the neuroanatomical basis of this interplay between both subcortical structures remains sparse and is mainly derived from work in primates. Here, in rodents, we have studied the existence of a potential disynaptic connection between the subthalamic nucleus (STN) and the cerebellar cortex as has been demonstrated earlier for the primate. A mixture of unmodified rabies virus (RABV: CVS 11) and cholera toxin B-subunit (CTb) was injected at places in the posterior cerebellar cortex of nine rats. The survival time was chosen to allow for disynaptic retrograde transneuronal infection of RABV. We examined the STN for neurons infected with RABV in all nine cases and related the results with the location of the RABV/CTb injection site, which ranged from the vermis of lobule VII, to the paravermis and hemispheres of the paramedian lobule and crus 2a. We found that cases with injection sites in the vermis of lobule VII showed prominent RABV labeling in the STN. In contrast, almost no subthalamic labeling was noted in cases with paravermal or hemispheral injection sites. We show circumstantial evidence that not only the pontine nuclei but also the pedunculotegmental nucleus may act as the intermediary in the connection from STN to cerebellar cortex. This finding implies that in the rat the STN links disynaptically to the vermal part of lobule VII of the cerebellar cortex, without any major involvement of the cerebellar areas that are linked to sensorimotor functions. As vermal lobule VII recently has been shown to process disynaptic input from the retrosplenial and orbitofrontal cortices, we hypothesize that in the rat the subthalamic input to cerebellar function might be used to influence more prominently non-motor functions of the cerebellum than motor functions. This latter aspect seems to contradict the primate results and could point to a more elaborate interaction between basal ganglia and cerebellum in more demanding motor tasks.
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Affiliation(s)
- Saad Jwair
- Department of Neuroscience, Erasmus Medical Center Rotterdam, Netherlands
| | - Patrice Coulon
- Institut de Neurosciences de la Timone, Aix-Marseille Université, CNRS Marseille, France
| | - Tom J H Ruigrok
- Department of Neuroscience, Erasmus Medical Center Rotterdam, Netherlands
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