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Jerrold vitek

Simeng Zhang, Allison T Connolly, Lauren Madden, Jerrold L Vitek, Matthew D Johnson
Local field potential (LFP) recordings along a deep brain stimulation (DBS) lead can provide useful feedback for titrating DBS therapy. However, conventional DBS leads with four cylindrical macroelectrodes likely undersample the spatial distribution of sinks and sources in a given brain region. In this study, we investigated the spectral power and spatial feature sizes of LFP activity in non-human primate subthalamic nucleus and globus pallidus using chronically implanted 32-channel directional DBS arrays.
 Approach: Subthalamic nucleus and globus pallidus LFP signals were recorded from directional DBS arrays in the resting state and during a reach-and-retrieval task in two non-human primates in naïve and parkinsonian conditions...
April 13, 2018: Journal of Neural Engineering
YiZi Xiao, Filippo Agnesi, Edward M Bello, Simeng Zhang, Jerrold L Vitek, Matthew D Johnson
Deep brain stimulation (DBS) therapy is a potent tool for treating a range of brain disorders. High frequency stimulation (HFS) patterns used in DBS therapy are known to modulate neuronal spike rates and patterns in the stimulated nucleus; however, the spatial distribution of these modulated responses are not well understood. Computational models suggest that HFS modulates a volume of tissue spatially concentrated around the active electrode. Here, we tested this theory by investigating modulation of spike rates and patterns in non-human primate motor thalamus while stimulating the cerebellar-receiving area of motor thalamus, the primary DBS target for treating Essential Tremor...
February 1, 2018: Scientific Reports
Takao Hashimoto, Abirami Muralidharan, Kunihiro Yoshida, Tetsuya Goto, Takehiro Yako, Kenneth B Baker, Jerrold L Vitek
Objectives: We investigated the effects of deep brain stimulation (DBS) or lesions of the ventral intermediate nucleus (Vim) of the thalamus for spinocerebellar ataxia (SCA) and examined the pathophysiological role of neuronal activity of the Vim underlying ataxia. Methods: Five patients with SCA with cortical atrophy (ages 60-69 years; 2 sporadic and three familial SCA) and five patients with essential tremor (ET) (ages 57-71 years) were treated with Vim surgery...
January 2018: Annals of Clinical and Translational Neurology
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
Cynthia S Kubu, Scott E Cooper, Andre Machado, Thomas Frazier, Jerrold Vitek, Paul J Ford
OBJECTIVE: To report prospective repeated measures data detailing the perceived benefit of deep brain stimulation (DBS) on the most commonly cited symptom and activity goals identified by patients with Parkinson disease. METHODS: Fifty-two participants were recruited from a consecutive series. Participants completed a semi-structured interview soliciting their symptom and behavioral goals and corresponding visual analog scales measuring perceived symptom severity and limits to goal attainment...
January 10, 2017: Neurology
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
Birgit R Plantinga, Yasin Temel, Yuval Duchin, Kâmil Uludağ, Rémi Patriat, Alard Roebroeck, Mark Kuijf, Ali Jahanshahi, Bart Ter Haar Romenij, Jerrold Vitek, Noam Harel
Deep brain stimulation of the subthalamic nucleus (STN) is a widely performed surgical treatment for patients with Parkinson's disease. The goal of the surgery is to place an electrode centered in the motor region of the STN while lowering the effects of electrical stimulation on the non-motor regions. However, distinguishing the motor region from the neighboring associative and limbic areas in individual patients using imaging modalities was until recently difficult to obtain in vivo. Here, using ultra-high field MR imaging, we have performed a dissection of the subdivisions of the STN of individual Parkinson's disease patients...
September 26, 2016: NeuroImage
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
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