Scholars@Duke
Nikki Pelot

Nikki Pelot

Research Scientist
Biomedical Engineering

Selected Publications

Highly efficient modeling and optimization of neural fiber responses to electrical stimulation.

Journal Article Nature communications · August 2024 Peripheral neuromodulation has emerged as a powerful modality for controlling physiological functions and treating a variety of medical conditions including chronic pain and organ dysfunction. The underlying complexity of the nonlinear responses to electri ... Full text Cite

Computational models of compound nerve action potentials: Efficient filter-based methods to quantify effects of tissue conductivities, conduction distance, and nerve fiber parameters.

Journal Article PLoS computational biology · March 2024 BackgroundPeripheral nerve recordings can enhance the efficacy of neurostimulation therapies by providing a feedback signal to adjust stimulation settings for greater efficacy or reduced side effects. Computational models can accelerate the develo ... Full text Cite

Calcium image analysis in the moving gut.

Journal Article Neurogastroenterology and motility · December 2023 BackgroundThe neural control of gastrointestinal muscle relies on circuit activity whose underlying motifs remain limited by small-sample calcium imaging recordings confounded by motion artifact, paralytics, and muscle dissections. We present a se ... Full text Cite

Validated computational models predict vagus nerve stimulation thresholds in preclinical animals and humans.

Journal Article Journal of neural engineering · June 2023 Objective.We demonstrated how automated simulations to characterize electrical nerve thresholds, a recently published open-source software for modeling stimulation of peripheral nerves, can be applied to simulate accurately nerve responses to electr ... Full text Cite

Fibers in smaller fascicles have lower activation thresholds with cuff electrodes due to thinner perineurium and smaller cross-sectional area.

Journal Article Journal of neural engineering · April 2023 Objective. In nerve stimulation therapies, fibers in larger fascicles generally have higher activation thresholds, but the mechanisms are not well understood. We implemented and analyzed computational models to uncover the effects of morphological p ... Full text Cite

Spatially selective stimulation of the pig vagus nerve to modulate target effect versus side effect.

Journal Article Journal of neural engineering · February 2023 Electrical stimulation of the cervical vagus nerve using implanted electrodes (VNS) is FDA-approved for the treatment of drug-resistant epilepsy, treatment-resistant depression, and most recently, chronic ischemic stroke rehabilitation. However, VNS is cri ... Full text Cite

Measuring and modeling the effects of vagus nerve stimulation on heart rate and laryngeal muscles.

Journal Article Bioelectronic medicine · February 2023 BackgroundReduced heart rate (HR) during vagus nerve stimulation (VNS) is associated with therapy for heart failure, but stimulation frequency and amplitude are limited by patient tolerance. An understanding of physiological responses to parameter ... Full text Cite

Fascicles split or merge every ∼560 microns within the human cervical vagus nerve.

Journal Article Journal of neural engineering · November 2022 Objective.Vagus nerve stimulation (VNS) is Food and Drug Administration-approved for epilepsy, depression, and obesity, and stroke rehabilitation; however, the morphological anatomy of the vagus nerve targeted by stimulatation is poorly understood. ... Full text Cite

ASCENT (Automated Simulations to Characterize Electrical Nerve Thresholds): A pipeline for sample-specific computational modeling of electrical stimulation of peripheral nerves.

Journal Article PLoS computational biology · September 2021 Electrical stimulation and block of peripheral nerves hold great promise for treatment of a range of disease and disorders, but promising results from preclinical studies often fail to translate to successful clinical therapies. Differences in neural anato ... Full text Cite

Non-monotonic kilohertz frequency neural block thresholds arise from amplitude- and frequency-dependent charge imbalance.

Journal Article Scientific reports · March 2021 Reversible block of nerve conduction using kilohertz frequency electrical signals has substantial potential for treatment of disease. However, the ability to block nerve fibers selectively is limited by poor understanding of the relationship between wavefo ... Full text Cite

Data from: Non-monotonic kilohertz frequency neural block thresholds arise from amplitude- and frequency-dependent charge imbalance

Dataset · January 25, 2021 Reversible block of nerve conduction using kilohertz frequency electrical signals has substantial potential for treatment of disease. However, the ability to block nerve fibers selectively is limited by poor understanding of the relationship between wavefo ... Full text Cite

Excitation properties of computational models of unmyelinated peripheral axons.

Journal Article Journal of neurophysiology · January 2021 Biophysically based computational models of nerve fibers are important tools for designing electrical stimulation therapies, investigating drugs that affect ion channels, and studying diseases that affect neurons. Although peripheral nerves are primarily c ... Full text Cite

Quantitative comparisons of block thresholds and onset responses for charge-balanced kilohertz frequency waveforms.

Journal Article Journal of neural engineering · September 2020 ObjectiveThere is growing interest in delivering kilohertz frequency (KHF) electrical signals to block conduction in peripheral nerves for treatment of various diseases. Previous studies used different KHF waveforms to achieve block, and it remain ... Full text Cite

Data from: Quantitative comparisons of block thresholds and onset responses for charge-balanced kilohertz frequency waveforms

Dataset · August 20, 2020 Objective: There is growing interest in delivering kilohertz frequency (KHF) electrical signals to block conduction in peripheral nerves for treatment of various diseases. Previous studies used different KHF waveforms to achieve block, and it remains uncle ... Full text Cite

Sources of off-target effects of vagus nerve stimulation using the helical clinical lead in domestic pigs.

Journal Article Journal of neural engineering · July 2020 ObjectiveClinical data suggest that efficacious vagus nerve stimulation (VNS) is limited by side effects such as cough and dyspnea that have stimulation thresholds lower than those for therapeutic outcomes. VNS side effects are putatively caused b ... Full text Cite

Functional vagotopy in the cervical vagus nerve of the domestic pig: implications for the study of vagus nerve stimulation.

Journal Article Journal of neural engineering · April 2020 ObjectiveGiven current clinical interest in vagus nerve stimulation (VNS), there are surprisingly few studies characterizing the anatomy of the vagus nerve in large animal models as it pertains to on-and off-target engagement of local fibers. We s ... Full text Cite

In vivo quantification of excitation and kilohertz frequency block of the rat vagus nerve.

Journal Article Journal of neural engineering · March 2020 ObjectiveThere is growing interest in treating diseases by electrical stimulation and block of peripheral autonomic nerves, but a paucity of studies on the excitation and block of small-diameter autonomic axons. We conducted in vivo quantification ... Full text Cite

Empirically Based Guidelines for Selecting Vagus Nerve Stimulation Parameters in Epilepsy and Heart Failure.

Journal Article Cold Spring Harbor perspectives in medicine · July 2019 Vagus nerve stimulation (VNS) is a promising therapy to treat patients with epilepsy and heart failure. Outcomes of preclinical studies and clinical trials indicate that the selection of stimulation parameters has a direct impact on therapeutic efficacy an ... Full text Cite

On the parameters used in finite element modeling of compound peripheral nerves.

Journal Article Journal of neural engineering · February 2019 ObjectiveComputational modeling is an important tool for developing and optimizing implantable neural stimulation devices, but requires accurate electrical and geometrical parameter values to improve predictive value. We quantified the effects of ... Full text Cite

Effects of vagal neuromodulation on feeding behavior.

Journal Article Brain research · August 2018 Implanted vagus nerve stimulation (VNS) for obesity was recently approved by the FDA. However, its efficacy and mechanisms of action remain unclear. Herein, we synthesize clinical and preclinical effects of VNS on feeding behavior and energy balance and di ... Full text Cite

Modeling Current Sources for Neural Stimulation in COMSOL.

Journal Article Frontiers in computational neuroscience · January 2018 Background: Computational modeling provides an important toolset for designing and analyzing neural stimulation devices to treat neurological disorders and diseases. Modeling enables efficient exploration of large parameter spaces, where preclinical ... Full text Cite

Modeling the response of small myelinated axons in a compound nerve to kilohertz frequency signals.

Journal Article Journal of neural engineering · August 2017 ObjectiveThere is growing interest in electrical neuromodulation of peripheral nerves, particularly autonomic nerves, to treat various diseases. Electrical signals in the kilohertz frequency (KHF) range can produce different responses, including c ... Full text Cite

Modeling the response of small myelinated and unmyelinated axons to kilohertz frequency signals

Conference International IEEE/EMBS Conference on Neural Engineering, NER · July 1, 2015 The effects of kilohertz frequency signals on action potential conduction in small myelinated (1 to 5.7 μm diameter) and unmyelinated axons are poorly understood, but could have important therapeutic applications. We developed a finite element model of a c ... Full text Cite

Clearance of depot vaccine SPIO-labeled antigen and substrate visualized using MRI.

Journal Article Vaccine · December 2014 Immunotherapies, including peptide-based vaccines, are a growing area of cancer research, and understanding their mechanism of action is crucial for their continued development and clinical application. Exploring the biodistribution of vaccine components m ... Full text Cite

Quantification of superparamagnetic iron oxide using inversion recovery balanced steady-state free precession.

Journal Article Magnetic resonance imaging · July 2013 Cellular and molecular MRI trafficking studies using superparamagnetic iron oxide (SPIO) have greatly improved non-invasive investigations of disease progression and drug efficacy, but thus far, these studies have largely been restricted to qualitative ass ... Full text Cite

Abstract 4285: Visualizing cancer vaccine clearance in vivo using magnetic resonance imaging

Journal Article Cancer Research · April 15, 2012 AbstractMagnetic Resonance Imaging (MRI) is a powerful tool in the evaluation of immunotherapies, since it permits non-invasive longitudinal assessment of tumor growth, and as our group has previously demons ... Full text Cite