scholarly journals The development of microfabricated solenoids with magnetic cores for micromagnetic neural stimulation

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Adam Khalifa ◽  
Mohsen Zaeimbashi ◽  
Tony X. Zhou ◽  
Seyed Mahdi Abrishami ◽  
Neville Sun ◽  
...  
Keyword(s):  
Metal Electrode ◽  
Magnetic Core ◽  
Neural Stimulation ◽  
Proof Of Concept ◽  
Magnetic Cores ◽  
Wide Range ◽  
Foreign Body Reactions ◽  
Electrode Contact ◽  
Psychiatric Conditions ◽  
The Brain

AbstractElectrical stimulation via invasive microelectrodes is commonly used to treat a wide range of neurological and psychiatric conditions. Despite its remarkable success, the stimulation performance is not sustainable since the electrodes become encapsulated by gliosis due to foreign body reactions. Magnetic stimulation overcomes these limitations by eliminating the need for a metal-electrode contact. Here, we demonstrate a novel microfabricated solenoid inductor (80 µm × 40 µm) with a magnetic core that can activate neuronal tissue. The characterization and proof-of-concept of the device raise the possibility that micromagnetic stimulation solenoids that are small enough to be implanted within the brain may prove to be an effective alternative to existing electrode-based stimulation devices for chronic neural interfacing applications.

scholarly journals Bio-Inspired Modality Fusion for Active Speaker Detection

2021 ◽  
Vol 11 (8) ◽  
pp. 3397
Author(s):  
Gustavo Assunção ◽  
Nuno Gonçalves ◽  
Paulo Menezes
Keyword(s):  
Superior Colliculus ◽  
Visual Information ◽  
Human Beings ◽  
Validation Process ◽  
Detection Approach ◽  
Wide Range ◽  
Speaker Detection ◽  
The One ◽  
The Brain ◽  
Fusion Ability

Human beings have developed fantastic abilities to integrate information from various sensory sources exploring their inherent complementarity. Perceptual capabilities are therefore heightened, enabling, for instance, the well-known "cocktail party" and McGurk effects, i.e., speech disambiguation from a panoply of sound signals. This fusion ability is also key in refining the perception of sound source location, as in distinguishing whose voice is being heard in a group conversation. Furthermore, neuroscience has successfully identified the superior colliculus region in the brain as the one responsible for this modality fusion, with a handful of biological models having been proposed to approach its underlying neurophysiological process. Deriving inspiration from one of these models, this paper presents a methodology for effectively fusing correlated auditory and visual information for active speaker detection. Such an ability can have a wide range of applications, from teleconferencing systems to social robotics. The detection approach initially routes auditory and visual information through two specialized neural network structures. The resulting embeddings are fused via a novel layer based on the superior colliculus, whose topological structure emulates spatial neuron cross-mapping of unimodal perceptual fields. The validation process employed two publicly available datasets, with achieved results confirming and greatly surpassing initial expectations.

Normal saline as a natural intravascular contrast agent for dynamic perfusion-weighted MRI of the brain: Proof of concept at 1.5T

2016 ◽  
Vol 44 (6) ◽  
pp. 1580-1591 ◽  
Author(s):  
Hernán Jara ◽  
Asim Mian ◽  
Osamu Sakai ◽  
Stephan W. Anderson ◽  
Mitchel J. Horn ◽  
...  
Keyword(s):  
Contrast Agent ◽  
Normal Saline ◽  
Proof Of Concept ◽  
Intravascular Contrast Agent ◽  
The Brain

Senses of Vibration

2012 ◽  
Author(s):  
Shelly Trower
Keyword(s):  
Sensory Experience ◽  
Cultural Imaginary ◽  
Wide Range ◽  
History Of ◽  
The Senses ◽  
To Come ◽  
The Brain

The study of the senses has become a rich topic in recent years. Senses of Vibration explores a wide range of sensory experience and makes a decisive new contribution to this growing field by focussing not simply on the senses as such, but on the material experience - vibration - that underpins them. This is the first book to take the theme of vibration as central, offering an interdisciplinary history of the phenomenon and its reverberations in the cultural imaginary. It tracks vibration through the work of a wide range of writers, including physiologists (who thought vibrations in the nerves delivered sensations to the brain), physicists (who claimed that light, heat, electricity and other forms of energy were vibratory), spiritualists (who figured that spiritual energies also existed in vibratory form), and poets and novelists from Coleridge to Dickens and Wells. Senses of Vibration is a work of scholarship that cuts through a range of disciplines and will reverberate for many years to come.

The impact of SARS-Cov-2 on the Nervous system and Mental Health

2021 ◽  
Vol 19 ◽  
Author(s):  
Mohamed Said Boulkrane ◽  
Victoria Ilina ◽  
Roman Melchakov ◽  
Mikhail Arisov ◽  
Julia Fedotova ◽  
...  
Keyword(s):  
Mental Health ◽  
Respiratory Illness ◽  
World Health ◽  
Current Review ◽  
Wide Range ◽  
Serious Disease ◽  
Health Organization ◽  
The Impact ◽  
The Brain ◽  
Severe Acute Respiratory Illness

: The World Health Organization declared the pandemic situation caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) in March 2020, but the detailed pathophysiological mechanisms of Coronavirus disease 2019 (COVID-19) are not yet completely understood. Therefore, to date, few therapeutic options are available for patients with mild-moderate or serious disease. In addition to systemic and respiratory symptoms, several reports have documented various neurological symptoms and impairments of mental health. The current review aims to provide the available evidence about the effects of SARS-CoV-2 infection on mental health. The present data suggest that SARS-CoV-2 produces a wide range of impairments and disorders of the brain. However, a limited number of studies investigated the neuroinvasive potential of SARS-CoV-2. Although the main features and outcomes of COVID-19 are linked to severe acute respiratory illness. The possible damages on the brain should be considered, too.

scholarly journals Harmonic Brain Modes: A Unifying Framework for Linking Space and Time in Brain Dynamics

2017 ◽  
Vol 24 (3) ◽  
pp. 277-293 ◽  
Author(s):  
Selen Atasoy ◽  
Gustavo Deco ◽  
Morten L. Kringelbach ◽  
Joel Pearson
Keyword(s):  
Neural Activity ◽  
Brain Activity ◽  
Activity Patterns ◽  
Structural Connectivity ◽  
Building Blocks ◽  
Mental States ◽  
Brain Dynamics ◽  
Space And Time ◽  
Wide Range ◽  
The Brain

A fundamental characteristic of spontaneous brain activity is coherent oscillations covering a wide range of frequencies. Interestingly, these temporal oscillations are highly correlated among spatially distributed cortical areas forming structured correlation patterns known as the resting state networks, although the brain is never truly at “rest.” Here, we introduce the concept of harmonic brain modes—fundamental building blocks of complex spatiotemporal patterns of neural activity. We define these elementary harmonic brain modes as harmonic modes of structural connectivity; that is, connectome harmonics, yielding fully synchronous neural activity patterns with different frequency oscillations emerging on and constrained by the particular structure of the brain. Hence, this particular definition implicitly links the hitherto poorly understood dimensions of space and time in brain dynamics and its underlying anatomy. Further we show how harmonic brain modes can explain the relationship between neurophysiological, temporal, and network-level changes in the brain across different mental states ( wakefulness, sleep, anesthesia, psychedelic). Notably, when decoded as activation of connectome harmonics, spatial and temporal characteristics of neural activity naturally emerge from the interplay between excitation and inhibition and this critical relation fits the spatial, temporal, and neurophysiological changes associated with different mental states. Thus, the introduced framework of harmonic brain modes not only establishes a relation between the spatial structure of correlation patterns and temporal oscillations (linking space and time in brain dynamics), but also enables a new dimension of tools for understanding fundamental principles underlying brain dynamics in different states of consciousness.

Estimation-Based Control of a Magnetic Endoscope without Device Localization

2018 ◽  
Vol 03 (01) ◽  
pp. 1850002 ◽  
Author(s):  
Janis Edelmann ◽  
Andrew J. Petruska ◽  
Bradley J. Nelson
Keyword(s):  
Field Experiments ◽  
Control Method ◽  
Initial Conditions ◽  
Medical Procedures ◽  
Proof Of Concept ◽  
Wide Range ◽  
Trajectory Length ◽  
Lung Phantom ◽  
Average Control ◽  
Inspection Task

Magnetically controlled catheters and endoscopes can improve minimally invasive procedures as a result of their increased maneuverability when combined with modern magnetic steering systems. However, such systems have two distinct shortcomings: they require continuous information about the location of the instrument inside the human body and they rely on models that accurately capture the device behavior, which are difficult to obtain in realistic settings. To address both of these issues, we propose a control algorithm that continuously estimates a magnetic endoscope’s response to changes in the actuating magnetic field. Experiments in a structured visual environment show that the control method is able to follow image-based trajectories under different initial conditions with an average control error that measures 1.8 % of the trajectory length. The usefulness for medical procedures is demonstrated with a bronchoscopic inspection task. In a proof-of-concept study, a custom 2[Formula: see text]mm diameter miniature camera endoscope is navigated through an anatomically correct lung phantom in a clinician-controlled manner. This represents the first demonstration of the controlled manipulation of a magnetic device without localization, which is critical for a wide range of medical procedures.

scholarly journals Stabilizing electrodeposition in elastic solid electrolytes containing immobilized anions

2016 ◽  
Vol 2 (7) ◽  
pp. e1600320 ◽  
Author(s):  
Mukul D. Tikekar ◽  
Lynden A. Archer ◽  
Donald L. Koch
Keyword(s):  
Elastic Solid ◽  
Present Theory ◽  
Metal Electrode ◽  
Mitigation Strategies ◽  
Factors Affecting ◽  
Wide Range ◽  
Current Densities ◽  
Morphological Instabilities ◽  
The Stability

Ion transport–driven instabilities in electrodeposition of metals that lead to morphological instabilities and dendrites are receiving renewed attention because mitigation strategies are needed for improving rechargeability and safety of lithium batteries. The growth rate of these morphological instabilities can be slowed by immobilizing a fraction of anions within the electrolyte to reduce the electric field at the metal electrode. We analyze the role of elastic deformation of the solid electrolyte with immobilized anions and present theory combining the roles of separator elasticity and modified transport to evaluate the factors affecting the stability of planar deposition over a wide range of current densities. We find that stable electrodeposition can be easily achieved even at relatively high current densities in electrolytes/separators with moderate polymer-like mechanical moduli, provided a small fraction of anions are immobilized in the separator.

Minds and brains: angels, humans, and brutes

1982 ◽  
Vol 57 (3) ◽  
pp. 309-315
Author(s):  
Mortimer J. Adler
Keyword(s):  
Nervous System ◽  
Animal Behavior ◽  
Personal Experience ◽  
Human Beings ◽  
Content Type ◽  
The Past ◽  
Wide Range ◽  
Conceptual Thought ◽  
The Brain ◽  
Fine Print

✓ In his 1982 Cushing oration, a distinguished philosopher, author, and discerning critic presents a distillate of his phenomenally wide range of personal experience and his familiarity with the great books and teachers of the present and the past. He explores the differences and relationships between human beings, brute animals, and machines. Knowledge of the brain and nervous system contribute to the explanation of all aspects of animal behavior, intelligence, and mentality, but cannot completely explain human conceptual thought.

scholarly journals Induction of WNT16 via Peptide-mRNA Nanoparticle-Based Delivery Maintains Cartilage Homeostasis

Pharmaceutics ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 73
Author(s):  
Huimin Yan ◽  
Ying Hu ◽  
Antonina Akk ◽  
Muhammad Farooq Rai ◽  
Hua Pan ◽  
...  
Keyword(s):  
Messenger Rna ◽  
Treatment Options ◽  
Cartilage Explants ◽  
Joint Disease ◽  
Chondrocyte Apoptosis ◽  
Proof Of Concept ◽  
Human Cartilage ◽  
Cartilage Homeostasis ◽  
Wide Range ◽  
Significant Disability

Osteoarthritis (OA) is a progressive joint disease that causes significant disability and pain and for which there are limited treatment options. We posit that delivery of anabolic factors that protect and maintain cartilage homeostasis will halt or retard OA progression. We employ a peptide-based nanoplatform to deliver Wingless and the name Int-1 (WNT) 16 messenger RNA (mRNA) to human cartilage explants. The peptide forms a self-assembled nanocomplex of approximately 65 nm in size when incubated with WNT16 mRNA. The complex is further stabilized with hyaluronic acid (HA) for enhanced cellular uptake. Delivery of peptide-WNT16 mRNA nanocomplex to human cartilage explants antagonizes canonical β-catenin/WNT3a signaling, leading to increased lubricin production and decreased chondrocyte apoptosis. This is a proof-of-concept study showing that mRNA can be efficiently delivered to articular cartilage, an avascular tissue that is poorly accessible even when drugs are intra-articularly (IA) administered. The ability to accommodate a wide range of oligonucleotides suggests that this platform may find use in a broad range of clinical applications.

scholarly journals Ganglioside GM1 Targets Astrocytes to Stimulate Cerebral Energy Metabolism

2021 ◽  
Vol 12 ◽  
Author(s):  
Charles Finsterwald ◽  
Sara Dias ◽  
Pierre J. Magistretti ◽  
Sylvain Lengacher
Keyword(s):  
Molecular Mechanisms ◽  
Neuroprotective Effect ◽  
Brain Diseases ◽  
Mitochondrial Activity ◽  
Ganglioside Gm1 ◽  
Neuroprotective Effects ◽  
Wide Range ◽  
Cord Injury ◽  
Clinical Benefits ◽  
The Brain

Gangliosides are major constituents of the plasma membrane and are known to promote a number of physiological actions in the brain, including synaptic plasticity and neuroprotection. In particular, the ganglioside GM1 was found to have a wide range of preclinical and clinical benefits in brain diseases such as spinal cord injury, Huntington’s disease and Parkinson’s disease. However, little is known about the underlying cellular and molecular mechanisms of GM1 in the brain. In the present study, we show that GM1 exerts its actions through the promotion of glycolysis in astrocytes, which leads to glucose uptake and lactate release by these cells. In astrocytes, GM1 stimulates the expression of several genes involved in the regulation of glucose metabolism. GM1 also enhances neuronal mitochondrial activity and triggers the expression of neuroprotection genes when neurons are cultured in the presence of astrocytes. Finally, GM1 leads to a neuroprotective effect in astrocyte-neuron co-culture. Together, these data identify a previously unrecognized mechanism mediated by astrocytes by which GM1 exerts its metabolic and neuroprotective effects.

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