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Jerrold L Vitek

David Escobar Sanabria, Luke A Johnson, Shane D Nebeck, Jianyu Zhang, Matthew D Johnson, Kenneth B Baker, Gregory F Molnar, Jerrold L Vitek
Oscillatory neural activity in different frequency bands and phase-amplitude coupling (PAC) are hypothesized to be biomarkers of Parkinson's disease (PD) that could explain dysfunction in the motor circuit and be used for closed-loop deep brain stimulation (DBS). How these putative biomarkers change from the normal to the parkinsonian state across nodes in the motor circuit and within the same subject, however, remains unknown. In this study, we characterized how parkinsonism and vigilance altered oscillatory activity and PAC within the primary motor cortex (M1), subthalamic nucleus (STN), and globus pallidus (GP) in two nonhuman primates...
November 1, 2017: Journal of Neurophysiology
Jing Wang, Luke A Johnson, Alicia L Jensen, Kenneth B Baker, Gregory F Molnar, Matthew D Johnson, Jerrold L Vitek
A number of studies suggest that Parkinson's disease (PD) is associated with alterations of neuronal activity patterns in the basal-ganglia-thalamocortical circuit. There are limited electrophysiological data, however, describing how the premotor cortex, which is involved in movement and decision-making, is likely impacted in PD. In this study, spontaneous local field potential (LFP) and single unit neuronal activity were recorded in the dorsal premotor area of nonhuman primates in both the naïve and parkinsonian state using the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of parkinsonism...
June 1, 2017: Journal of Neurophysiology
Franziska Hopfner, Dietrich Haubenberger, Wendy R Galpern, Katrina Gwinn, Ashlee Van't Veer, Samantha White, Kailash Bhatia, Charles H Adler, David Eidelberg, William Ondo, Glenn T Stebbins, Caroline M Tanner, Rick C Helmich, Fred A Lenz, Roy V Sillitoe, David Vaillancourt, Jerrold L Vitek, Elan D Louis, Holly A Shill, Matthew P Frosch, Tatiana Foroud, Gregor Kuhlenbäumer, Andrew Singleton, Claudia M Testa, Mark Hallett, Rodger Elble, Günther Deuschl
Essential tremor (ET) is a common cause of significant disability, but its etiologies and pathogenesis are poorly understood. Research has been hampered by the variable definition of ET and by non-standardized research approaches. The National Institute of Neurological Disorders and Stroke (USA) invited experts in ET and related fields to discuss current knowledge, controversies, and gaps in our understanding of ET and to develop recommendations for future research. Discussion focused on phenomenology and phenotypes, therapies and clinical trials, pathophysiology, pathology, and genetics...
December 2016: Parkinsonism & related Disorders
Luke A Johnson, Shane D Nebeck, Abirami Muralidharan, Matthew D Johnson, Kenneth B Baker, Jerrold L Vitek
BACKGROUND: Incorporating feedback controls based on real-time measures of pathological brain activity may improve deep brain stimulation (DBS) approaches for the treatment of Parkinson's disease (PD). Excessive beta oscillations in subthalamic nucleus (STN) local field potentials (LFP) have been proposed as a potential biomarker for closed-loop DBS (CL-DBS). OBJECTIVE: In a non-human primate PD model we compared CL-DBS, which delivered stimulation only when STN LFP beta activity was elevated, to traditional continuous DBS (tDBS)...
November 2016: Brain Stimulation
Jing Wang, Shane Nebeck, Abirami Muralidharan, Matthew D Johnson, Jerrold L Vitek, Kenneth B Baker
BACKGROUND: Novel deep brain stimulation (DBS) paradigms are being explored in an effort to further optimize therapeutic outcome for patients with Parkinson's disease (PD). One approach, termed 'Coordinated Reset' (CR) DBS, was developed to target pathological oscillatory network activity. with desynchronizing effects and associated therapeutic benefit hypothesized to endure beyond cessation of stimulus delivery. OBJECTIVE: To characterize the acute and carry-over effects of low-intensity CR DBS versus traditional DBS (tDBS) in the region of the subthalamic nucleus (STN)...
July 2016: Brain Stimulation
Allison T Connolly, Rio J Vetter, Jamille F Hetke, Benjamin A Teplitzky, Daryl R Kipke, David S Pellinen, David J Anderson, Kenneth B Baker, Jerrold L Vitek, Matthew D Johnson
GOAL: Develop and characterize the functionality of a novel thin-film probe technology with a higher density of electrode contacts than are currently available with commercial deep brain stimulation (DBS) lead technology. Such technology has potential to enhance the spatial precision of DBS and enable a more robust approach to sensing local field potential activity in the context of adaptive DBS strategies. METHODS: Thin-film planar arrays were microfabricated and then assembled on a cylindrical carrier to achieve a lead with 3-D conformation...
January 2016: IEEE Transactions on Bio-medical Engineering
Allison T Connolly, Abirami Muralidharan, Claudia Hendrix, Luke Johnson, Rahul Gupta, Scott Stanslaski, Tim Denison, Kenneth B Baker, Jerrold L Vitek, Matthew D Johnson
OBJECTIVE: Using the Medtronic Activa® PC + S system, this study investigated how passive joint manipulation, reaching behavior, and deep brain stimulation (DBS) modulate local field potential (LFP) activity in the subthalamic nucleus (STN) and globus pallidus (GP). APPROACH: Five non-human primates were implanted unilaterally with one or more DBS leads. LFPs were collected in montage recordings during resting state conditions and during motor tasks that facilitate the expression of parkinsonian motor signs...
December 2015: Journal of Neural Engineering
Alan D Dorval, Abirami Muralidharan, Alicia L Jensen, Kenneth B Baker, Jerrold L Vitek
INTRODUCTION: The motor symptoms of Parkinson's disease (PD) present with pathological neuronal activity in the basal ganglia. Although neuronal firing rate changes in the globus pallidus internus (GPi) and externus (GPe) are reported to underlie the development of PD motor signs, firing rates change inconsistently, vary confoundingly with some therapies, and are poor indicators of symptom severity. METHODS: We explored the relationship between parkinsonian symptom severity and the effectiveness with which pallidal neurons transmit information...
November 2015: Parkinsonism & related Disorders
Laura M Zitella, Benjamin A Teplitzky, Paul Yager, Heather M Hudson, Katelynn Brintz, Yuval Duchin, Noam Harel, Jerrold L Vitek, Kenneth B Baker, Matthew D Johnson
Deep brain stimulation (DBS) in the pedunculopontine tegmental nucleus (PPTg) has been proposed to alleviate medically intractable gait difficulties associated with Parkinson's disease. Clinical trials have shown somewhat variable outcomes, stemming in part from surgical targeting variability, modulating fiber pathways implicated in side effects, and a general lack of mechanistic understanding of DBS in this brain region. Subject-specific computational models of DBS are a promising tool to investigate the underlying therapy and side effects...
2015: Frontiers in Computational Neuroscience
Filippo Agnesi, Abirami Muralidharan, Kenneth B Baker, Jerrold L Vitek, Matthew D Johnson
High-frequency stimulation is known to entrain spike activity downstream and upstream of several clinical deep brain stimulation (DBS) targets, including the cerebellar-receiving area of thalamus (VPLo), subthalamic nucleus (STN), and globus pallidus (GP). Less understood are the fidelity of entrainment to each stimulus pulse, whether entrainment patterns are stationary over time, and how responses differ among DBS targets. In this study, three rhesus macaques were implanted with a single DBS lead in VPLo, STN, or GP...
August 2015: Journal of Neurophysiology
Laura M Zitella, YiZi Xiao, Benjamin A Teplitzky, Daniel J Kastl, Yuval Duchin, Kenneth B Baker, Jerrold L Vitek, Gregor Adriany, Essa Yacoub, Noam Harel, Matthew D Johnson
Structural brain imaging provides a critical framework for performing stereotactic and intraoperative MRI-guided surgical procedures, with procedural efficacy often dependent upon visualization of the target with which to operate. Here, we describe tools for in vivo, subject-specific visualization and demarcation of regions within the brainstem. High-field 7T susceptibility-weighted imaging and diffusion-weighted imaging of the brain were collected using a customized head coil from eight rhesus macaques. Fiber tracts including the superior cerebellar peduncle, medial lemniscus, and lateral lemniscus were identified using high-resolution probabilistic diffusion tractography, which resulted in three-dimensional fiber tract reconstructions that were comparable to those extracted from sequential application of a two-dimensional nonlinear brain atlas warping algorithm...
2015: PloS One
Allison T Connolly, Alicia L Jensen, Edward M Bello, Theoden I Netoff, Kenneth B Baker, Matthew D Johnson, Jerrold L Vitek
While beta oscillations often occur within the parkinsonian basal ganglia, how these oscillations emerge from a naive state and change with disease severity is not clear. To address this question, a progressive, nonhuman primate model of Parkinson's disease was developed using staged injections of MPTP. Within each parkinsonian state (naive, mild, moderate, and severe), spontaneous local field potentials were recorded throughout the sensorimotor globus pallidus. In the naive state, beta oscillations (11-32 Hz) occurred in half of the recordings, indicating spontaneous beta oscillations in globus pallidus are not pathognomonic...
April 15, 2015: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Allison T Connolly, Alicia L Jensen, Kenneth B Baker, Jerrold L Vitek, Matthew D Johnson
The firing patterns of neurons in the basal ganglia are known to become more oscillatory and synchronized from healthy to parkinsonian conditions. Similar changes have been observed with local field potentials (LFPs). In this study, we used an unbiased machine learning approach to investigate the utility of pallidal LFPs for discriminating the stages of a progressive parkinsonian model. A feature selection algorithm was used to identify subsets of LFP features that provided the most discriminatory information for severity of parkinsonian motor signs...
July 2015: Journal of Neurophysiology
Christopher L Pulliam, Dustin A Heldman, Tseganesh H Orcutt, Thomas O Mera, Joseph P Giuffrida, Jerrold L Vitek
BACKGROUND: Deep brain stimulation (DBS) is a well-established treatment for Parkinson's disease (PD). Optimization of DBS settings can be a challenge due to the number of variables that must be considered, including presence of multiple motor signs, side effects, and battery life. METHODS: Nine PD subjects visited the clinic for programming at approximately 1, 2, and 4 months post-surgery. During each session, various stimulation settings were assessed and subjects performed motor tasks while wearing a motion sensor to quantify tremor and bradykinesia...
April 2015: Parkinsonism & related Disorders
Luke A Johnson, Weidong Xu, Kenneth B Baker, Jianyu Zhang, Jerrold L Vitek
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a well-established surgical therapy for advanced Parkinson's disease (PD). An emerging hypothesis is that the therapeutic benefit of DBS is derived from direct modulation of primary motor cortex (M1), yet little is known about the influence of STN DBS on individual neurons in M1. We investigated the effect of STN DBS, delivered at discrete interval intensities (20, 40, 60, 80, and 100%) of corticospinal tract threshold (CSTT), on motor performance and M1 neuronal activity in a naive nonhuman primate...
April 1, 2015: Journal of Neurophysiology
Jeff M Bronstein, Michele Tagliati, Cameron McIntyre, Robert Chen, Tyler Cheung, Eric L Hargreaves, Zvi Israel, Michael Moffitt, Erwin B Montgomery, Paul Stypulkowski, Jay Shils, Timothy Denison, Jerrold Vitek, Jens Volkman, Jeffrey Wertheimer, Michael S Okun
OBJECTIVE: Deep brain stimulation (DBS) is an effective therapy for the treatment of a number of movement and neuropsychiatric disorders. The effectiveness of DBS is dependent on the density and location of stimulation in a given brain area. Adjustments are made to optimize clinical benefits and minimize side effects. Until recently, clinicians would adjust DBS settings using a voltage mode, where the delivered voltage remained constant. More recently, a constant-current mode has become available where the programmer sets the current and the stimulator automatically adjusts the voltage as impedance changes...
February 2015: Neuromodulation: Journal of the International Neuromodulation Society
Jens Volkmann, Joerg Mueller, Günther Deuschl, Andrea A Kühn, Joachim K Krauss, Werner Poewe, Lars Timmermann, Daniela Falk, Andreas Kupsch, Anatol Kivi, Gerd-Helge Schneider, Alfons Schnitzler, Martin Südmeyer, Jürgen Voges, Alexander Wolters, Matthias Wittstock, Jan-Uwe Müller, Sascha Hering, Wilhelm Eisner, Jan Vesper, Thomas Prokop, Marcus Pinsker, Christoph Schrader, Manja Kloss, Karl Kiening, Kai Boetzel, Jan Mehrkens, Inger Marie Skogseid, Jon Ramm-Pettersen, Georg Kemmler, Kailash P Bhatia, Jerrold L Vitek, Reiner Benecke
BACKGROUND: Cervical dystonia is managed mainly by repeated botulinum toxin injections. We aimed to establish whether pallidal neurostimulation could improve symptoms in patients not adequately responding to chemodenervation or oral drug treatment. METHODS: In this randomised, sham-controlled trial, we recruited patients with cervical dystonia from centres in Germany, Norway, and Austria. Eligible patients (ie, those aged 18-75 years, disease duration ≥3 years, Toronto Western Spasmodic Torticollis Rating Scale [TWSTRS] severity score ≥15 points) were randomly assigned (1:1) to receive active neurostimulation (frequency 180 Hz; pulse width 120 μs; amplitude 0·5 V below adverse event threshold) or sham stimulation (amplitude 0 V) by computer-generated randomisation lists with randomly permuted block lengths stratified by centre...
September 2014: Lancet Neurology
Filippo Agnesi, Matthew D Johnson, Jerrold L Vitek
Chronic deep brain stimulation (DBS) has become a widely accepted surgical treatment for medication-refractory movement disorders and is under evaluation for a variety of neurological disorders. In order to create opportunities to improve treatment efficacy, streamline parameter selection, and foster new potential applications, it is important to have a clear and comprehensive understanding of how DBS works. Although early hypothesis proposed that high-frequency electrical stimulation inhibited neuronal activity proximal to the active electrode, recent studies have suggested that the output of the stimulated nuclei is paradoxically activated by DBS...
2013: Handbook of Clinical Neurology
Filippo Agnesi, Allison T Connolly, Kenneth B Baker, Jerrold L Vitek, Matthew D Johnson
Deep brain stimulation (DBS) therapy has become an essential tool for treating a range of brain disorders. In the resting state, DBS is known to regularize spike activity in and downstream of the stimulated brain target, which in turn has been hypothesized to create informational lesions. Here, we specifically test this hypothesis using repetitive joint articulations in two non-human Primates while recording single-unit activity in the sensorimotor globus pallidus and motor thalamus before, during, and after DBS in the globus pallidus (GP) GP-DBS resulted in: (1) stimulus-entrained firing patterns in globus pallidus, (2) a monophasic stimulus-entrained firing pattern in motor thalamus, and (3) a complete or partial loss of responsiveness to joint position, velocity, or acceleration in globus pallidus (75%, 12/16 cells) and in the pallidal receiving area of motor thalamus (ventralis lateralis pars oralis, VLo) (38%, 21/55 cells)...
2013: PloS One
Svjetlana Miocinovic, Suvarchala Somayajula, Shilpa Chitnis, Jerrold L Vitek
Deep brain stimulation (DBS) is an effective surgical treatment for medication-refractory hypokinetic and hyperkinetic movement disorders, and it is being explored for a variety of other neurological and psychiatric diseases. Deep brain stimulation has been Food and Drug Administration-approved for essential tremor and Parkinson disease and has a humanitarian device exemption for dystonia and obsessive-compulsive disorder. Neurostimulation is the fruit of decades of both technical and scientific advances in the field of basic neuroscience and functional neurosurgery...
February 2013: JAMA Neurology
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