Vagus nerve stimulation paired with tactile training improved sensory function in a chronic stroke patient

Background: Recent studies indicate that vagus nerve stimulation (VNS) paired with rehabilitation can enhance neural plasticity in the primary sensory and motor cortices, improve forelimb function after stroke in animal models and improve motor function in patients with arm weakness after stroke. OBJECTIVE:To gain “first-in-man” experience of VNS paired with tactile training in a patient with severe sensory impairment after stroke. Methods: During the long-term follow-up phase of a clinical trial of VNS paired with motor rehabilitation, a 71-year-old man who had made good motor recovery had ongoing severe sensory loss in his left hand and arm. He received VNS paired with tactile therapy in an attempt to improve his sensory function. During twenty 2-hour sessions, each passive and active tactile event was paired with a 0.5 second burst of 0.8 mA VNS. Sensory function was measured before, halfway through, and after this therapy. Results: The patient did not report any side effects during or following VNS+Tactile therapy. Quantitative measures revealed lasting and clinically meaningful improvements in tactile threshold, proprioception, and stereognosis. After VNS+Tactile therapy, the patient was able to detect tactile stimulation to his affected hand that was eight times less intense, identify the joint position of his fingers in the affected hand three times more often, and identify everyday objects using his affected hand seven times more often, compared to baseline. Conclusions: Sensory function significantly improved in this man following VNS paired with tactile stimulation. This approach merits further study in controlled clinical trials

Methods, systems, and devices for pairing vagus nerve stimulation with motor therapy in stroke patients

A method of treating motor deficits in a stroke patient, comprising assessing a patient's motor deficits, determining therapeutic goals for the patient, based on the patient's motor deficits, selecting therapeutic tasks based on the therapeutic goals, performing each of the selected therapeutic tasks repetitively, observing the performance of the therapeutic tasks, initiating the stimulation of the vagus nerve manually at approximately a predetermined moment during the performance of the therapeutic tasks, stimulating the vagus nerve of the patient during the performance of the selected therapeutic tasks, and improving the patient's motor deficits.Board of Regents, University of Texas Syste

Methods, systems, and devices for pairing vagus nerve stimulation with motor therapy in stroke patients

A method of treating motor deficits in a stroke patient, comprising assessing a patient's motor deficits, determining therapeutic goals for the patient, based on the patient's motor deficits, selecting therapeutic tasks based on the therapeutic goals, performing each of the selected therapeutic tasks repetitively, observing the performance of the therapeutic tasks, initiating the stimulation of the vagus nerve manually at approximately a predetermined moment during the performance of the therapeutic tasks, stimulating the vagus nerve of the patient during the performance of the selected therapeutic tasks, and improving the patient's motor deficits.Board of Regents, University of Texas Syste

Implanted miniaturized antenna for brain computer interface applications: Analysis and design

Implantable Brain Computer Interfaces (BCIs) are designed to provide real-time control signals for prosthetic devices, study brain function, and/or restore sensory information lost as a result of injury or disease. Using Radio Frequency (RF) to wirelessly power a BCI could widely extend the number of applications and increase chronic in-vivo viability. However, due to the limited size and the electromagnetic loss of human brain tissues, implanted miniaturized antennas suffer low radiation efficiency. This work presents simulations, analysis and designs of implanted antennas for a wireless implantable RF-powered brain computer interface application. The results show that thin (on the order of 100 micrometers thickness) biocompatible insulating layers can significantly impact the antenna performance. The proper selection of the dielectric properties of the biocompatible insulating layers and the implantation position inside human brain tissues can facilitate efficient RF power reception by the implanted antenna. While the results show that the effects of the human head shape on implanted antenna performance is somewhat negligible, the constitutive properties of the brain tissues surrounding the implanted antenna can significantly impact the electrical characteristics (input impedance, and operational frequency) of the implanted antenna. Three miniaturized antenna designs are simulated and demonstrate that maximum RF power of up to 1.8 milli-Watts can be received at 2 GHz when the antenna implanted around the dura, without violating the Specific Absorption Rate (SAR) limits. © 2014 Zhao et al

Geologic controls on reservoir quality of the Hunton and Viola limestones in the Leach Field, Jackson County, Kansas

Master of ScienceDepartment of GeologyMatthew W. TottenThe area of study for this project is the Leach Field, which is located in Jackson County, Kansas. Production in the Leach Field has historically been disappointing, with 388,787 barrels of oil being produced since the field’s discovery in 1963 (KGS, 2015). Production of the field has been highly variable, with only 20,568 barrels of oil being produced in the last 20 years. Economic and other concerns that have impacted production and production rates of the field include: low oil prices soon after its discovery, numerous changes of ownership, and lack of significant production infrastructure in the area. Stroke of Luck Energy & Exploration, LLC. has recently purchased the majority of the leases and wells in the Leach Field, and is reestablishing the field as a productive oil field. Plans include: washing down several plugged and abandoned wells, and drill new wells to increase production in the field. The goal of this study was to determine the major geologic factors controlling reservoir quality in the Hunton and Viola Limestone Formations in the Leach Field, so that a future exploration model can be developed to help increase and stabilize the field's overall production. This model was created by applying several testing methods including: well logging analysis, microscope analysis, and subsurface mapping. Based on these results it was determined that the quality of the reservoir rocks is controlled by the degree of dolomitizaiton in both formations. Reservoir quality is as important as structure in determining well productivity in the Leach Field

The Fourth Bioelectronic Medicine Summit "Technology Targeting Molecular Mechanisms": current progress, challenges, and charting the future.

There is a broad and growing interest in Bioelectronic Medicine, a dynamic field that continues to generate new approaches in disease treatment. The fourth bioelectronic medicine summit "Technology targeting molecular mechanisms" took place on September 23 and 24, 2020. This virtual meeting was hosted by the Feinstein Institutes for Medical Research, Northwell Health. The summit called international attention to Bioelectronic Medicine as a platform for new developments in science, technology, and healthcare. The meeting was an arena for exchanging new ideas and seeding potential collaborations involving teams in academia and industry. The summit provided a forum for leaders in the field to discuss current progress, challenges, and future developments in Bioelectronic Medicine. The main topics discussed at the summit are outlined here

Stream segregation in the anesthetized auditory cortex

Auditory stream segregation describes the way that sounds are perceptually segregated into groups or streams on the basis of perceptual attributes such as pitch or spectral content. For sequences of pure tones, segregation depends on the tones' proximity in frequency and time. In the auditory cortex (and elsewhere) responses to sequences of tones are dependent on stimulus conditions in a similar way to the perception of these stimuli. However, although highly dependent on stimulus conditions, perception is also clearly influenced by factors unrelated to the stimulus, such as attention. Exactly how ‘bottom-up’ sensory processes and non-sensory ‘top-down’ influences interact is still not clear. Here, we recorded responses to alternating tones (ABAB …) of varying frequency difference (FD) and rate of presentation (PR) in the auditory cortex of anesthetized guinea-pigs. These data complement previous studies, in that top-down processing resulting from conscious perception should be absent or at least considerably attenuated. Under anesthesia, the responses of cortical neurons to the tone sequences adapted rapidly, in a manner sensitive to both the FD and PR of the sequences. While the responses to tones at frequencies more distant from neuron best frequencies (BFs) decreased as the FD increased, the responses to tones near to BF increased, consistent with a release from adaptation, or forward suppression. Increases in PR resulted in reductions in responses to all tones, but the reduction was greater for tones further from BF. Although asymptotically adapted responses to tones showed behavior that was qualitatively consistent with perceptual stream segregation, responses reached asymptote within 2 s, and responses to all tones were very weak at high PRs (>12 tones per second). A signal-detection model, driven by the cortical population response, made decisions that were dependent on both FD and PR in ways consistent with perceptual stream segregation. This included showing a range of conditions over which decisions could be made either in favor of perceptual integration or segregation, depending on the model ‘decision criterion’. However, the rate of ‘build-up’ was more rapid than seen perceptually, and at high PR responses to tones were sometimes so weak as to be undetectable by the model. Under anesthesia, adaptation occurs rapidly, and at high PRs tones are generally poorly represented, which compromises the interpretation of the experiment. However, within these limitations, these results complement experiments in awake animals and humans. They generally support the hypothesis that ‘bottom-up’ sensory processing plays a major role in perceptual organization, and that processes underlying stream segregation are active in the absence of attention

Rapid Encoding and Perception of Novel Odors in the Rat

To gain insight into which parameters of neural activity are important in shaping the perception of odors, we combined a behavioral measure of odor perception with optical imaging of odor representations at the level of receptor neuron input to the rat olfactory bulb. Instead of the typical test of an animal's ability to discriminate two familiar odorants by exhibiting an operant response, we used a spontaneously expressed response to a novel odorant—exploratory sniffing—as a measure of odor perception. This assay allowed us to measure the speed with which rats perform spontaneous odor discriminations. With this paradigm, rats discriminated and began responding to a novel odorant in as little as 140 ms. This time is comparable to that measured in earlier studies using operant behavioral readouts after extensive training. In a subset of these trials, we simultaneously imaged receptor neuron input to the dorsal olfactory bulb with near-millisecond temporal resolution as the animal sampled and then responded to the novel odorant. The imaging data revealed that the bulk of the discrimination time can be attributed to the peripheral events underlying odorant detection: receptor input arrives at the olfactory bulb 100–150 ms after inhalation begins, leaving only 50–100 ms for central processing and response initiation. In most trials, odor discrimination had occurred even before the initial barrage of receptor neuron firing had ceased and before spatial maps of activity across glomeruli had fully developed. These results suggest a coding strategy in which the earliest-activated glomeruli play a major role in the initial perception of odor quality, and place constraints on coding and processing schemes based on simple changes in spike rate

A transformation from temporal to ensemble coding in a model of piriform cortex

Different coding strategies are used to represent odor information at various stages of the mammalian olfactory system. A temporal latency code represents odor identity in olfactory bulb (OB), but this temporal information is discarded in piriform cortex (PCx) where odor identity is instead encoded through ensemble membership. We developed a spiking PCx network model to understand how this transformation is implemented. In the model, the impact of OB inputs activated earliest after inhalation is amplified within PCx by diffuse recurrent collateral excitation, which then recruits strong, sustained feedback inhibition that suppresses the impact of later-responding glomeruli. We model increasing odor concentrations by decreasing glomerulus onset latencies while preserving their activation sequences. This produces a multiplexed cortical odor code in which activated ensembles are robust to concentration changes while concentration information is encoded through population synchrony. Our model demonstrates how PCx circuitry can implement multiplexed ensemble-identity/temporal-concentration odor coding

Identification and treatment of the visual processing asymmetry in MS patients with optic neuritis: The Pulfrich phenomenon

BACKGROUND: The Pulfrich phenomenon (PF) is the illusory perception that an object moving linearly along a 2-D plane appears to instead follow an elliptical 3-D trajectory, a consequence of inter-eye asymmetry in the timing of visual object identification in the visual cortex; with optic neuritis as a common etiology. OBJECTIVE: We have designed an objective method to identify the presence and magnitude of the PF, in conjunction with a cooresponding strategy by which to abolish the effect; with monocular application of neutral density filters to the less affected fellow eye, in patients with MS and a history of optic neuropathy (e.g. related to acute optic neuritis or subclinical optic neuropathy). METHODS: Twenty-three MS patients with a history of acute unilateral or bilateral optic neuritis, and ten healthy control subjects (HC) were recruited to participate in a pilot study to assess our strategy. Subjects were asked to indicate whether a linearly moving pendulum ball followed a linear 2-D path versus an illusory 3-D elliptical object-motion trajectory, by reporting the ball's approximation to one of nine horizontally-oriented colored wires that were positioned parallel to one another and horizontal to the linear pendulum path. Perceived motion of the bob that moved along wires behind or in front (along the 'Z' plane) of the middle reference wire indicated an illusory elliptical trajectory of ball motion consistent with the PF. RESULTS: When the neutral density filter titration was applied to the fellow eye the severity of the PF decreased, eventually being fully abolished in all but one patient. The magnitude of neutral density filtering required correlated to the severity of the patient's initial PF magnitude (p < 0.001). CONCLUSIONS: We ascertained the magnitude of the visual illusion associated with the PF, and the corresponding magnitude of neutral density filtering necessary to abolish it