A5085073238- Neural dynamics and brain function
- stochastic dynamics and bifurcation
- Neuroscience and Neural Engineering
- Neuroscience of respiration and sleep
- Nonlinear Dynamics and Pattern Formation
- Photoreceptor and optogenetics research
- EEG and Brain-Computer Interfaces
- Neurological disorders and treatments
- Sleep and Wakefulness Research
- Advanced Memory and Neural Computing
- Neuroendocrine regulation and behavior
- Functional Brain Connectivity Studies
- Neurobiology and Insect Physiology Research
- Muscle activation and electromyography studies
- Neural Networks and Applications
- Transcranial Magnetic Stimulation Studies
- Biomedical and Engineering Education
- Vagus Nerve Stimulation Research
- Cardiac electrophysiology and arrhythmias
- Advanced Neuroimaging Techniques and Applications
- Neuroscience and Neuropharmacology Research
- Advanced Materials Characterization Techniques
- Heart Rate Variability and Autonomic Control
- Gene Regulatory Network Analysis
- Mindfulness and Compassion Interventions
The Wallace H. Coulter Department of Biomedical Engineering
2010-2024
Georgia Institute of Technology
2013-2023
Emory University
2004-2022
Physical Sciences (United States)
2022
NOAA Physical Sciences Laboratory
2021
University of Oslo
2007
DuPont (United States)
1996-2002
National Institute of Neurological Disorders and Stroke
1999-2000
National Institutes of Health
1998-2000
Rice University
1994-1999
A network of oscillatory bursting neurons with excitatory coupling is hypothesized to define the primary kernel for respiratory rhythm generation in pre-Bötzinger complex (pre-BötC) mammals. Two minimal models these are proposed. In model 1, arises via fast activation and slow inactivation a persistent Na + current I NaP-h . 2, fast-activating NaP K KS both models, action potentials generated currents. The two have few differences parameters facilitate rigorous comparison different...
Abstract Deep brain stimulation (DBS) of the subcallosal cingulate (SCC) can provide long-term symptom relief for treatment-resistant depression (TRD) 1 . However, achieving stable recovery is unpredictable 2 , typically requiring trial-and-error adjustments due to individual trajectories and subjective reporting 3 We currently lack objective brain-based biomarkers guide clinical decisions by distinguishing natural transient mood fluctuations from situations intervention. To address this...
We have proposed models for the ionic basis of oscillatory bursting respiratory pacemaker neurons in pre-Bötzinger complex. In this paper, we investigate frequency control and synchronization these model when coupled by excitatory amino-acid-mediated synapses controlled convergent synaptic inputs modeled as tonic excitation. Simulations pairs identical cells reveal that increasing excitation increases synchronous bursting, while strength coupling between decreases bursting. Low levels extend...
We measured persistent Na(+) current and membrane properties of bursting-pacemaker nonbursting inspiratory neurons the neonatal rat pre-Bötzinger complex (pre-BötC) in brain stem slice preparations with a rhythmically active respiratory network vitro. In whole-cell recordings, slow voltage ramps (</=100 mV/s) inactivated fast, spike-generating yielded N-shaped current-voltage relationships nonmonotonic, negative-slope regions between -60 -35 mV when voltage-sensitive component was isolated....
We used the testable predictions of mathematical models proposed by Butera et al. to evaluate cellular, synaptic, and population-level components hypothesis that respiratory rhythm in mammals is generated vitro pre-Bötzinger complex (pre-BötC) a heterogeneous population pacemaker neurons coupled fast excitatory synapses. prepared thin brain stem slices from neonatal rats capture pre-BötC maintain inspiratory-related motor activity vitro. recorded extracellularly found: intrinsic bursting...
Adaptively optimizing experiments has the potential to significantly reduce number of trials needed build parametric statistical models neural systems. However, application adaptive methods neurophysiology been limited by severe computational challenges. Since most neurons are high-dimensional systems, requires computing integrations and optimizations in real time. Here we present a fast algorithm for choosing informative stimulus maximizing mutual information between data unknown parameters...
Conduction block using high-frequency alternating current (HFAC) stimulation has been shown to reversibly conduction through various nerves. However, unlike simulations and experiments on myelinated fibers, prior experimental work in our lab the sea-slug, Aplysia, found a nonmonotonic relationship between frequency blocking thresholds unmyelinated fibers. To resolve this discrepancy, we investigated effect of HFAC waveforms compound action potential sciatic nerve frogs. Maximal produces...
Kilohertz electrical stimulation (KES) has been shown to induce repeatable and reversible nerve conduction block in animal models. In this study, we characterized the ability of KES stimuli selectively specific components stimulated activity using vivo preparations rat sciatic vagus nerves. frequency range 5-70 kHz amplitudes 0.1-3.0 mA were applied. Compound action potentials evoked either or sensory stimulation, was assessed through direct recordings muscle force measurements. Distinct...
The ability to experimentally perturb biological systems has traditionally been limited static pre-programmed or operator-controlled protocols. In contrast, real-time control allows dynamic probing of with perturbations that are computed on-the-fly during experimentation. Real-time applications for research available; however, these costly and often restrict the flexibility customization experimental Real-Time eXperiment Interface (RTXI) is an open source software platform achieving hard...
The estimation of action potential thresholds is a subjective process, which we quantified by surveying experienced electrophysiologists via software application that allowed them to select from several presented neuronal time series. Independent this survey, derived two nonparametric techniques for automating the detection an threshold time-series intracellular recordings. Both methods start with phase-space representation (dV/dt versus V). Method I detects maximum slope in phase space,...
The pre-Botzinger complex (pBC) is a vital subcircuit of the respiratory central pattern generator. Although existence neurons with pacemaker-like bursting properties in this network not questioned, their role rhythmogenesis unresolved. Modeling ideally suited to address debate because ease which biophysical parameters individual cells and architecture can be manipulated. We modeled parameter variability experimental data from pBC pacemaker nonpacemaker using modified version our previously...
Abstract Efferent activation of the cervical vagus nerve (cVN) dampens systemic inflammatory processes, potentially modulating a wide-range pathological conditions. In contrast, afferent cVN amplifies leading to hypothalamic-pituitary-adrenal (HPA) axis, sympathetic nervous system through greater splanchnic (GSN), and elevation pro-inflammatory cytokines. Ideally, clinically implement anti-inflammatory therapy via stimulation (cVNS) one should selectively activate efferent pathway....
Networks of oscillators produce vital activity in diverse natural systems. The dynamics these networks are frequently studied via computational models that assume weak coupling, yet this assumption has not been experimentally validated. We applied stimuli to neuronal Aplysia californica and deconvolved infinitesimal phase response curves (IPRCs) describe the a neuron. show IPRCs reliably predict for stimuli, independent stimulus waveform used. These range normal synaptic neurons, suggesting...
The widespread adoption of neural prosthetic devices is currently hindered by our inability to reliably record signals from chronically implanted electrodes. extent which the local tissue response electrodes influences recording failure not well understood. To investigate this phenomenon, impedance spectroscopy has shown promise for use as a non-invasive tool estimate microelectrodes. Here, we model spectra rats using well-established Cole model, and perform correlation analysis modeled...
Phase response curves (PRCs) for a single neuron are often used to predict the synchrony of mutually coupled neurons. Previous theoretical work on pulse-coupled oscillators single-pulse perturbations. We propose an alternate method in which functional PRCs (fPRCs) generated using train pulses applied at fixed delay after each spike, with PRC measured when phasic relationship between stimulus and subsequent spike has converged. The essential information is dependence recovery time from pulse...
This paper summarizes the discussions held during First IEEE Life Sciences Grand Challenges Conference, on October 4-5, 2012, at National Academy of Sciences, Washington, DC, and grand challenges identified by conference participants. Despite tremendous efforts to develop knowledge ability that are essential in addressing biomedical health problems using engineering methodologies, optimization this approach toward life sciences healthcare remains a challenge. The was aimed high-level...
The application of high-frequency alternating current (HFAC) stimulation to reversibly block conduction in peripheral nerves has been under investigation for decades. Computational studies have produced ambiguous results since they based on axon models that are perhaps not valid the which phenomenon demonstrated. Though simulations Hodgkin-Huxley unmyelinated nerve cable model used understand phenomena, isolated response an HFAC waveforms experimentally investigated. To effect homogenous...
The Real-time Experiment Interface (RTXI) is a fast and versatile real-time biological experimentation system based on Real-Time Linux. RTXI open source free, can be used with an extensive range of hardware, run Linux or Windows computers (when using the Live CD). currently extensively for two experiment types: dynamic patch clamp closed-loop stimulation pattern control in neural cardiac single cell electrophysiology. includes standard plug-ins implementing commonly electrophysiology...