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Khatoun A, Asamoah B, Boogers A, Mc Laughlin M. Epicranial Direct Current Stimulation Suppresses Harmaline Tremor in Rats. Neuromodulation 2022:S1094-7159(22)01223-5. [DOI: 10.1016/j.neurom.2022.08.448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/19/2022] [Accepted: 08/01/2022] [Indexed: 10/14/2022]
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Sáenz-Farret M, Loh A, Boutet A, Germann J, Elias GJB, Kalia SK, Chen R, Lozano AM, Fasano A. Theta Burst Deep Brain Stimulation in Movement Disorders. Mov Disord Clin Pract 2021; 8:282-285. [PMID: 33681412 DOI: 10.1002/mdc3.13130] [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: 08/10/2020] [Revised: 11/19/2020] [Accepted: 11/23/2020] [Indexed: 11/09/2022] Open
Affiliation(s)
- Michel Sáenz-Farret
- Edmond J. Safra Program in Parkinson's Disease and Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology, UHN, Division of Neurology University of Toronto Toronto Ontario Canada
| | - Aaron Loh
- Department of Neurosurgery University of Toronto Toronto Ontario Canada
| | - Alexandre Boutet
- Department of Neurosurgery University of Toronto Toronto Ontario Canada.,Joint Department of Medical Imaging University of Toronto Toronto Ontario Canada
| | - Jürgen Germann
- Department of Neurosurgery University of Toronto Toronto Ontario Canada
| | - Gavin J B Elias
- Department of Neurosurgery University of Toronto Toronto Ontario Canada
| | - Suneil K Kalia
- Department of Neurosurgery University of Toronto Toronto Ontario Canada.,Krembil Research Institute Toronto Ontario Canada.,Center for Advancing Neurotechnological Innovation to Application (CRANIA) Toronto Ontario Canada
| | - Robert Chen
- Edmond J. Safra Program in Parkinson's Disease and Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology, UHN, Division of Neurology University of Toronto Toronto Ontario Canada.,Krembil Research Institute Toronto Ontario Canada
| | - Andres M Lozano
- Department of Neurosurgery University of Toronto Toronto Ontario Canada.,Krembil Research Institute Toronto Ontario Canada
| | - Alfonso Fasano
- Edmond J. Safra Program in Parkinson's Disease and Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital and Division of Neurology, UHN, Division of Neurology University of Toronto Toronto Ontario Canada.,Krembil Research Institute Toronto Ontario Canada.,Center for Advancing Neurotechnological Innovation to Application (CRANIA) Toronto Ontario Canada
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Bello EM, Agnesi F, Xiao Y, Dao J, Johnson MD. Frequency-dependent spike-pattern changes in motor cortex during thalamic deep brain stimulation. J Neurophysiol 2020; 124:1518-1529. [PMID: 32965147 DOI: 10.1152/jn.00198.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cerebellar-receiving area of the motor thalamus is the primary anatomical target for treating essential tremor with deep brain stimulation (DBS). Although neuroimaging studies have shown that higher stimulation frequencies in this target correlate with increased cortical metabolic activity, less is known about the cellular-level functional changes that occur in the primary motor cortex (M1) with thalamic stimulation and how these changes depend on the frequency of DBS. In this study, we used a preclinical animal model of DBS to collect single-unit spike recordings in M1 before, during, and after DBS targeting the cerebellar-receiving area of the motor thalamus (VPLo, nucleus ventralis posterior lateralis pars oralis). The effects of VPLo-DBS on M1 spike rates, interspike interval entropy, and peristimulus phase-locking were compared across stimulus pulse train frequencies ranging from 10 to 130 Hz. Although VPLo-DBS modulated the spike rates of 20-50% of individual M1 cells in a frequency-dependent manner, the population-level average spike rate only weakly depended on stimulation frequency. In contrast, the population-level entropy measure showed a pronounced decrease with high-frequency stimulation, caused by a subpopulation of cells that exhibited strong phase-locking and general spike-pattern regularization. Contrarily, low-frequency stimulation induced an entropy increase (spike-pattern disordering) in a relatively large portion of the recorded population, which diminished with higher stimulation frequencies. These results also suggest that changes in phase-locking and spike-pattern entropy are not necessarily equivalent pattern phenomena, but rather that they should both be weighed when quantifying stimulation-induced spike-pattern changes.NEW & NOTEWORTHY The network mechanisms of thalamic deep brain stimulation (DBS) are not well understood at the cellular level. This study investigated the neuronal firing rate and pattern changes in the motor cortex resulting from stimulation of the cerebellar-receiving area of the motor thalamus. We showed that there is a nonintuitive relationship between general entropy-based spike-pattern measures and phase-locked regularization to DBS.
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Affiliation(s)
- Edward M Bello
- Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Filippo Agnesi
- Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Yizi Xiao
- Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Joan Dao
- Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Matthew D Johnson
- Department of Biomedical Engineering, University of Minnesota, Minneapolis.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis
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Revuelta G, McGill C, Jensen JH, Bonilha L. Characterizing Thalamo-Cortical Structural Connectivity in Essential Tremor with Diffusional Kurtosis Imaging Tractography. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2019; 9:tre-09-690. [PMID: 31534829 PMCID: PMC6727860 DOI: 10.7916/tohm.v0.690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/31/2019] [Indexed: 12/26/2022]
Abstract
Background Neuromodulation of the cerebello-thalamo-cortical (CTC) circuit via thalamic stimulation is an effective therapy for essential tremor (ET). In order to develop non-invasive neuromodulation approaches, clinically relevant thalamo-cortical connections must be elucidated. Methods Twenty-eight subjects (18 ET patients and 10 controls) underwent MRI diffusional kurtosis imaging (DKI). A deterministic fiber-tracking algorithm based on DKI was used, with a seeding region placed at the ventral intermediate nucleus (Vim—located based on intraoperative physiology) to the ending regions at the supplementary motor area (SMA), pre-SMA, or primary motor cortex. One-tailed t-tests were performed to compare groups, and associations with tremor severity were determined by Pearson correlations. All p-values were adjusted for multiple comparisons using Bonferroni correction. Results There was a decrease in the mean diffusivity (MD) in patients compared to controls in all three tracts: Vim-M1 (ET 0.87, control 0.96, p < 0.01), Vim-SMA (ET 0.86, control 0.96, p < 0.05), and Vim-pre-SMA (ET 0.87, control 0.95, p < 0.05). There was a significant positive correlation between Tremor Rating Scale score and MK (r = 0.471, p = 0.033) and mean FA (r = 0.438, p = 0.045) for the Vim-SMA tract, and no significant correlation for the Vim-pre-SMA or Vim-M1 tracts was found. Discussion Patients with ET demonstrated a reinforcement of Vim-cortical connectivity, with higher Vim-SMA connectivity being associated with greater tremor severity. This finding suggests that the Vim-SMA connection is relevant to the underlying pathophysiology of ET, and inhibition of the SMA may be an effective therapeutic approach.
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Affiliation(s)
- Gonzalo Revuelta
- Department of Neurology, College of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Corinne McGill
- Department of Neuroscience, College of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Jens H Jensen
- Department of Neuroscience, College of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Leonardo Bonilha
- Department of Neurology, College of Medicine, Medical University of South Carolina, Charleston, SC, USA
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5
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Fasano A, Helmich RC. Tremor habituation to deep brain stimulation: Underlying mechanisms and solutions. Mov Disord 2019; 34:1761-1773. [PMID: 31433906 DOI: 10.1002/mds.27821] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 07/01/2019] [Accepted: 07/18/2019] [Indexed: 12/14/2022] Open
Abstract
DBS of the ventral intermediate nucleus is an extremely effective treatment for essential tremor, although a waning benefit is observed after a variable time in a variable proportion of patients (ranging from 0% to 73%), a concept historically defined as "tolerance." Tolerance is currently an established concept in the medical community, although there is debate on its real existence. In fact, very few publications have actually addressed the problem, thus making tolerance a typical example of science based on "eminence rather than evidence." The underpinnings of the phenomena associated with the progressive loss of DBS benefit are not fully elucidated, although the interplay of different-not mutually exclusive-factors has been advocated. In this viewpoint, we gathered the evidence explaining the progressive loss of benefit observed after DBS. We grouped these factors in three categories: disease-related factors (tremor etiology and progression); surgery-related factors (electrode location, microlesional effect and placebo); and stimulation-related factors (not optimized stimulation, stimulation-induced side effects, habituation, and tremor rebound). We also propose possible pathophysiological explanations for the phenomenon and define a nomenclature of the associated features: early versus late DBS failure; tremor rebound versus habituation (to be preferred over tolerance). Finally, we provide a practical approach for preventing and treating this loss of DBS benefit, and we draft a possible roadmap for the research to come. © 2019 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Alfonso Fasano
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, UHN, Toronto, Ontario, Canada; Division of Neurology, University of Toronto, Toronto, Ontario, Canada.,Krembil Brain Institute, Toronto, Ontario, Canada.,CenteR for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, Ontario, Canada
| | - Rick C Helmich
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands
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6
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Isayama R, Chen R, Lang AE, Deuschl G, Fasano A. Tremor with congenital mirror movements: evidence of involvement of the primary motor cortex in tremor. Eur J Neurol 2019; 26:e66-e67. [PMID: 31034740 DOI: 10.1111/ene.13901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 12/17/2018] [Indexed: 10/26/2022]
Affiliation(s)
- R Isayama
- Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Krembil Research Institute, Toronto, ON, Canada
| | - R Chen
- Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Krembil Research Institute, Toronto, ON, Canada.,Krembil Brain Institute, Toronto, ON, Canada
| | - A E Lang
- Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Krembil Research Institute, Toronto, ON, Canada.,Krembil Brain Institute, Toronto, ON, Canada
| | - G Deuschl
- Krembil Brain Institute, Toronto, ON, Canada.,Department of Neurology, Christian-Albrechts-Universitätzu Kiel, Kiel, Germany
| | - A Fasano
- Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Krembil Research Institute, Toronto, ON, Canada.,Krembil Brain Institute, Toronto, ON, Canada
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7
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Witjas-Slucki T. Surgical treatments for tremors. Rev Neurol (Paris) 2018; 174:615-620. [PMID: 30224158 DOI: 10.1016/j.neurol.2018.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/20/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
Stereotactic surgery is an increasingly popular option for disabling tremors whenever it is insufficiently improved by drug treatment. Surgical approaches are expanding. Thalamic deep brain stimulation is one of the most efficacious treatments. Its recent technological advances with adaptive stimulation and new electrodes configuration will allow a more physiological stimulation. However, a reappraisal of less invasive, new lesioning procedures is underway. Gamma Knife thalamotomy and magnetic resonance-guided focused ultrasounds encounter very few contraindications. Recent studies reported their efficacy on tremor control and safety profile. Besides the ventralis intermedius nucleus of the thalamus, alternative targets are also emerging. The effectiveness of surgical therapies on essential tremor and Parkinson's disease tremor is well established. For more uncommon tremors, preliminary studies are encouraging. All these surgical therapies can be proposed as treatment option for medically refractory tremors.
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Affiliation(s)
- T Witjas-Slucki
- Service de neurologie et pathologie du mouvement, UMR 7289 CNRS Aix-Marseille université, institut de neurosciences de la Timone, CHU Timone, Marseille, boulevard, Jean-Moulin, 13005 Marseille, France.
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8
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Lin PC, Chen KH, Yang BS, Chen YJ. A digital assessment system for evaluating kinetic tremor in essential tremor and Parkinson's disease. BMC Neurol 2018. [PMID: 29523097 PMCID: PMC5845296 DOI: 10.1186/s12883-018-1027-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Background Spiral drawing on papers is a common tremor evaluation tool for diagnosing patients with essential tremor (ET) or Parkinson’s disease (PD). No standard drawing methods and parameters that use graphic tablets are yet available for objective evaluation. Methods This study established a tremor assessment system for tremor severity by using graphic tablets. Twelve patients with ET and twelve patients with PD were tested to establish system algorithms, and six additional patients were tested with the developed system to evaluate its performance. The patients also performed spiral drawing with three guiding paradigms on a graphic tablet: traced along a given spiral (S1), performed freehand drawing (S2), and traced along a guiding point (S3). Three parameters were calculated to quantify tremor severity: the means of radial difference per radian (|dr/dθ|), the means of radial difference per second (|dr/dt|), and the area under curve (AUC) of the frequency spectrum of the velocity. Each patient’s drawing was also evaluated using a visual rating scale (VRS) by experienced physicians. The interrater reliability was examined to identify the most consistent test paradigm. Results The parameter |dr/dθ| and AUC correlated well with the VRS (R > 0.8) in S1, S2 and S3 tests. The S1 test presented the best interrater reliability (Weighted Kappa coefficient, k = 0.80) among three tests. The Weighted Kappa coefficients are 0.67 and 0.71 in S2 and S3 tests, respectively. Conclusions We developed three different guiding paradigms for spiral drawing on a digital graphic tablet for clinical tests. Three parameters were calculated to represent the tremor severity in spiral drawing and used to quantify temporal and spatial characteristics of tremor, and provided good correlation with current clinical assessments. The test “traced along a given spiral” is recommended due to its good interrater reliability. Electronic supplementary material The online version of this article (10.1186/s12883-018-1027-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Po-Chieh Lin
- Department of Mechanical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu City, 30010, Taiwan
| | - Kai-Hsiang Chen
- Neurology Division, National Taiwan University Hospital, Hsinchu Branch, Hsinchu City, 300, Taiwan
| | - Bing-Shiang Yang
- Department of Mechanical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu City, 30010, Taiwan. .,Institute of Biomedical Engineering, National Chiao Tung University, Hsinchu City, 300, Taiwan.
| | - Yu-Jung Chen
- Department of Mechanical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu City, 30010, Taiwan
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Lavano A, Guzzi G, Chirchiglia D. Cortical neuromodulation for neuropathic pain and Parkinson disease: Where are we? Neurol Neurochir Pol 2018; 52:75-78. [PMID: 29180075 DOI: 10.1016/j.pjnns.2017.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 11/05/2017] [Indexed: 11/29/2022]
Abstract
Cortex neuromodulation is promising approach for treatment of some neurological conditions, especially neuropathic pain and Parkinson's disease. Effects of non-invasive cortical stimulation are short lived; transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) may be useful to assess the suitability for invasive cortical stimulation. Direct cortical stimulation (DCS) is the method able to provide long-lasting effects in treatment of neuropathic pain and some symptoms of Parkinson's disease through the use of totally implantable systems that ensure a chronic stimulation.
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Affiliation(s)
- Angelo Lavano
- Department of Neurosurgery, University "Magna Graecia" of Catanzaro, Italy.
| | - Giusy Guzzi
- Department of Neurosurgery, University "Magna Graecia" of Catanzaro, Italy
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Di Lazzaro V, Mazzone P, Insola A, Florio L, Capone F, Ranieri F. Spinal cord stimulation for pain treatment failed to modify disease progression in a patient with amyotrophic lateral sclerosis. Clin Neurol Neurosurg 2017; 163:108-109. [PMID: 29096137 DOI: 10.1016/j.clineuro.2017.10.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/21/2017] [Accepted: 10/15/2017] [Indexed: 11/15/2022]
Affiliation(s)
- Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128 Rome, Italy; Fondazione Alberto Sordi - Research Institute for Ageing, Rome, Italy.
| | | | | | - Lucia Florio
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128 Rome, Italy; Fondazione Alberto Sordi - Research Institute for Ageing, Rome, Italy
| | - Fioravante Capone
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128 Rome, Italy; Fondazione Alberto Sordi - Research Institute for Ageing, Rome, Italy
| | - Federico Ranieri
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128 Rome, Italy; Fondazione Alberto Sordi - Research Institute for Ageing, Rome, Italy
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11
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Seo H, Jun SC. Multi-Scale Computational Models for Electrical Brain Stimulation. Front Hum Neurosci 2017; 11:515. [PMID: 29123476 PMCID: PMC5662877 DOI: 10.3389/fnhum.2017.00515] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 10/11/2017] [Indexed: 12/11/2022] Open
Abstract
Electrical brain stimulation (EBS) is an appealing method to treat neurological disorders. To achieve optimal stimulation effects and a better understanding of the underlying brain mechanisms, neuroscientists have proposed computational modeling studies for a decade. Recently, multi-scale models that combine a volume conductor head model and multi-compartmental models of cortical neurons have been developed to predict stimulation effects on the macroscopic and microscopic levels more precisely. As the need for better computational models continues to increase, we overview here recent multi-scale modeling studies; we focused on approaches that coupled a simplified or high-resolution volume conductor head model and multi-compartmental models of cortical neurons, and constructed realistic fiber models using diffusion tensor imaging (DTI). Further implications for achieving better precision in estimating cellular responses are discussed.
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Affiliation(s)
- Hyeon Seo
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Sung C. Jun
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, South Korea
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12
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Simultaneously Excitatory and Inhibitory Effects of Transcranial Alternating Current Stimulation Revealed Using Selective Pulse-Train Stimulation in the Rat Motor Cortex. J Neurosci 2017; 37:9389-9402. [PMID: 28847809 DOI: 10.1523/jneurosci.1390-17.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/03/2017] [Accepted: 08/10/2017] [Indexed: 12/13/2022] Open
Abstract
Transcranial alternating current stimulation (tACS) uses sinusoidal, subthreshold, electric fields to modulate cortical processing. Cortical processing depends on a fine balance between excitation and inhibition and tACS acts on both excitatory and inhibitory cortical neurons. Given this, it is not clear whether tACS should increase or decrease cortical excitability. We investigated this using transcranial current stimulation of the rat (all males) motor cortex consisting of a continuous subthreshold sine wave with short bursts of suprathreshold pulse-trains inserted at different phases to probe cortical excitability. We found that when a low-rate, long-duration, suprathreshold pulse-train was used, subthreshold cathodal tACS decreased cortical excitability and anodal tACS increased excitability. However, when a high-rate, short-duration, suprathreshold pulse-train was used this pattern was inverted. An integrate-and-fire model incorporating biophysical differences between cortical excitatory and inhibitory neurons could predict the experimental data and helped interpret these results. The model indicated that low-rate suprathreshold pulse-trains preferentially stimulate excitatory cortical neurons, whereas high-rate suprathreshold pulse-trains stimulate both excitatory and inhibitory neurons. If correct, this indicates that suprathreshold pulse-train stimulation may be able to selectively control the excitation-inhibition balance within a cortical network. The excitation-inhibition balance then likely plays an important role in determining whether subthreshold tACS will increase or decrease cortical excitability.SIGNIFICANCE STATEMENT Transcranial alternating current stimulation (tACS) is a noninvasive neuromodulation method that uses weak sinusoidal electric fields to modulate cortical activity. In healthy volunteers tACS can modulate perception, cognition, and motor function but the underlying neural mechanism is poorly understood. In this study, using rat motor cortex, we found that tACS effects are highly variable: applying the same tACS waveform to the same cortical area does not always give the same change in cortical excitability. An integrate-and-fire model incorporating excitatory pyramidal and inhibitory interneurons indicated that tACS effects likely depend on the cortical excitation-inhibition balance. When cortical activity is excitation dominated one particular tACS phase increases excitability, but when the cortical activity is inhibition dominated the same tACS phase actually decreases excitability.
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Rohani M, Fasano A. Focused Ultrasound for Essential Tremor: Review of the Evidence and Discussion of Current Hurdles. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2017; 7:462. [PMID: 28503363 PMCID: PMC5425801 DOI: 10.7916/d8z89jn1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 04/17/2017] [Indexed: 01/09/2023]
Abstract
Background While there is no breakthrough progress in the medical treatment of essential tremor (ET), in the past decades several remarkable achievements happened in the surgical field, such as radiofrequency thalamotomy, thalamic deep brain stimulation, and gamma knife thalamotomy. The most recent advance in this area is magnetic resonance-guided focused ultrasound (MRgFUS). Methods The purpose of this review is to discuss the new developments and trials of MRgFUS in the treatment of ET and other tremor disorders. Results MRgFUS is an incisionless surgery performed without anesthesia and ionizing radiation (no risk of cumulative dose and delayed side effects). Studies have shown the safety and effectiveness of unilateral MRgFUS-thalamotomy in the treatment of ET. It has been successfully used in a few patients with Parkinson’s disease-related tremor, and in fewer patients with fragile X-associated tremor/ataxia syndrome. The safety and long-term effects of the procedure are still unclear, as temporary and permanent adverse events have been reported as well as recurrence of tremor. Discussion MRgFUS is a promising new surgical approach with a number of unknowns and unsolved issues. It represents a valuable option particularly for patients who refused or could not be candidates for other procedures, deep brain stimulation in particular.
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Affiliation(s)
- Mohammad Rohani
- Department of Neurology, Hazrat Rasool Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Alfonso Fasano
- Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital and Division of Neurology, University of Toronto, Toronto, Ontario, Canada.,Krembil Research Institute, Toronto, Ontario, Canada
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Abstract
Currently available therapies for essential tremor (ET) provide sufficient control only for less than a half of patients and many unmet needs exist. This is in part due to the empiric nature of existing treatment options and persisting uncertainties about the pathogenesis of ET. The emerging concept of ET as a possible neurodegenerative disorder, better understanding of associated biochemical changes, including alterations in the γ-aminobutyric acid (GABA)-ergic system and gap junctions, and the identification of the role of the leucine-rich repeat and immunoglobulin-like domain-containing 1 (LINGO-1) gene in ET pathogenesis suggest new avenues for more targeted therapies. Here we review the most promising new approaches to treating ET, including allosteric modulation of GABA receptors and modifications of the LINGO-1 pathway. Medically refractory tremor can be successfully treated by high-frequency deep brain stimulation (DBS) of the ventral intermediate nucleus, but surgical therapies are also fraught with limitations due to adverse effects of stimulation and the loss of therapeutic response. The selection of additional thalamic and extrathalamic targets for electrode placements and the development of a closed-loop DBS system enabling automatic adjustment of stimulation parameters in response to changes in electrophysiologic brain activity are also reviewed. Tremor cancellation methods using exoskeleton and external hand-held devices are also briefly discussed.
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Affiliation(s)
- Peter Hedera
- Department of Neurology, Vanderbilt University, 465 21st Avenue South, 6140 MRB III, Nashville, TN 37240, USA
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15
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Di Lazzaro V, Pellegrino G, Capone F, Florio L, Dileone M, Cioni B, Ranieri F. Reduction of disease progression in a patient with amyotrophic lateral sclerosis after several years of epidural motor cortex stimulation. Brain Stimul 2016; 10:324-325. [PMID: 27931885 DOI: 10.1016/j.brs.2016.11.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 11/12/2016] [Accepted: 11/19/2016] [Indexed: 12/12/2022] Open
Affiliation(s)
- Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy; Fondazione Alberto Sordi, Research Institute for Ageing, Via Álvaro del Portillo 5, 00128, Rome, Italy.
| | - Giovanni Pellegrino
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy; IRCCS, Fondazione Ospedale San Camillo, Venice, Italy
| | - Fioravante Capone
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy; Fondazione Alberto Sordi, Research Institute for Ageing, Via Álvaro del Portillo 5, 00128, Rome, Italy
| | - Lucia Florio
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy; Fondazione Alberto Sordi, Research Institute for Ageing, Via Álvaro del Portillo 5, 00128, Rome, Italy
| | - Michele Dileone
- CINAC, HM Puerta del Sur, Hospitales de Madrid, CEU San Pablo University, Madrid, Spain
| | - Beatrice Cioni
- Neurosurgery, Università Cattolica - Fondazione Policlinico Gemelli, Rome, Italy
| | - Federico Ranieri
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy; Fondazione Alberto Sordi, Research Institute for Ageing, Via Álvaro del Portillo 5, 00128, Rome, Italy
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Effect of Anatomically Realistic Full-Head Model on Activation of Cortical Neurons in Subdural Cortical Stimulation-A Computational Study. Sci Rep 2016; 6:27353. [PMID: 27273817 PMCID: PMC4895150 DOI: 10.1038/srep27353] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/17/2016] [Indexed: 11/09/2022] Open
Abstract
Electrical brain stimulation (EBS) is an emerging therapy for the treatment of neurological disorders, and computational modeling studies of EBS have been used to determine the optimal parameters for highly cost-effective electrotherapy. Recent notable growth in computing capability has enabled researchers to consider an anatomically realistic head model that represents the full head and complex geometry of the brain rather than the previous simplified partial head model (extruded slab) that represents only the precentral gyrus. In this work, subdural cortical stimulation (SuCS) was found to offer a better understanding of the differential activation of cortical neurons in the anatomically realistic full-head model than in the simplified partial-head models. We observed that layer 3 pyramidal neurons had comparable stimulation thresholds in both head models, while layer 5 pyramidal neurons showed a notable discrepancy between the models; in particular, layer 5 pyramidal neurons demonstrated asymmetry in the thresholds and action potential initiation sites in the anatomically realistic full-head model. Overall, the anatomically realistic full-head model may offer a better understanding of layer 5 pyramidal neuronal responses. Accordingly, the effects of using the realistic full-head model in SuCS are compelling in computational modeling studies, even though this modeling requires substantially more effort.
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Haubenberger D, Abbruzzese G, Bain PG, Bajaj N, Benito-León J, Bhatia KP, Deuschl G, Forjaz MJ, Hallett M, Louis ED, Lyons KE, Mestre TA, Raethjen J, Stamelou M, Tan EK, Testa CM, Elble RJ. Transducer-based evaluation of tremor. Mov Disord 2016; 31:1327-36. [PMID: 27273470 DOI: 10.1002/mds.26671] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 04/04/2016] [Accepted: 04/07/2016] [Indexed: 11/11/2022] Open
Abstract
The International Parkinson and Movement Disorder Society established a task force on tremor that reviewed the use of transducer-based measures in the quantification and characterization of tremor. Studies of accelerometry, electromyography, activity monitoring, gyroscopy, digitizing tablet-based measures, vocal acoustic analysis, and several other transducer-based methods were identified by searching PubMed.gov. The availability, use, acceptability, reliability, validity, and responsiveness were reviewed for each measure using the following criteria: (1) used in the assessment of tremor; (2) used in published studies by people other than the developers; and (3) adequate clinimetric testing. Accelerometry, gyroscopy, electromyography, and digitizing tablet-based measures fulfilled all three criteria. Compared to rating scales, transducers are far more sensitive to changes in tremor amplitude and frequency, but they do not appear to be more capable of detecting a change that exceeds random variability in tremor amplitude (minimum detectable change). The use of transducer-based measures requires careful attention to their limitations and validity in a particular clinical or research setting. © 2016 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Dietrich Haubenberger
- Clinical Trials Unit, Office of the Clinical Director, National Institutes of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
| | | | - Peter G Bain
- Department of Neurology, Imperial College London, Charing Cross Hospital, London, United Kingdom
| | - Nin Bajaj
- Department of Neurology, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
| | - 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
| | - Kailash P Bhatia
- Sobell Department for Movement Neuroscience, UCL, Institute of Neurology, Queen Square, London, United Kingdom
| | - Günther Deuschl
- Department of Neurology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Maria João Forjaz
- National School of Public Health and Red de Investigación en Servicios Sanitarios y Enfermedades Crónicas (REDISSEC), Carlos III Institute of Health, Madrid, Spain
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Elan D Louis
- Departments of Neurology and Chronic Disease Epidemiology, Yale School of Medicine and Yale School of Public Health, Yale University, New Haven, Connecticut, USA
| | - Kelly E Lyons
- University of Kansas Medical Center, Kansas City, Kansas
| | - Tiago A Mestre
- Parkinson's disease and Movement Disorders Center, Division of Neurology, Department of Medicine, University of Ottawa, The Ottawa Hospital Research Institute, Ottawa Brain and Mind Research Institute, Ottawa, Ontario, Canada
| | - Jan Raethjen
- Department of Neurology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Maria Stamelou
- Neurology Department, University of Athens, Greece and Neurology Department, Philipps University, Marburg, Germany
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute (SGH campus), Duke NUS Medical School, Singapore General Hospital, Singapore
| | - Claudia M Testa
- Department of Neurology and Parkinson's and Movement Disorders Center, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
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Picillo M, Fasano A. Recent advances in Essential Tremor: Surgical treatment. Parkinsonism Relat Disord 2016; 22 Suppl 1:S171-5. [DOI: 10.1016/j.parkreldis.2015.09.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 11/26/2022]
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Fasano A, Deuschl G. Therapeutic advances in tremor. Mov Disord 2015; 30:1557-65. [DOI: 10.1002/mds.26383] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 07/29/2015] [Indexed: 12/12/2022] Open
Affiliation(s)
- Alfonso Fasano
- Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital-UHN, Division of Neurology, University of Toronto; Toronto Ontario Canada
| | - Günther Deuschl
- Department of Neurology; Christian-Albrechts-University Kiel; Germany
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