Download or read book Neural Recordings in the Brain Using Novel Movable MEMS Microelectrode Arrays written by Nathan Morrow Jackson and published by . This book was released on 2009 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Towards Adaptive Micro robotic Neural Interfaces written by Sindhu Anand and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in implantable MEMS technology has made possible adaptive micro-robotic implants that can track and record from single neurons in the brain. Development of autonomous neural interfaces opens up exciting possibilities of micro-robots performing standard electrophysiological techniques that would previously take researchers several hundred hours to train and achieve the desired skill level. It would result in more reliable and adaptive neural interfaces that could record optimal neural activity 24/7 with high fidelity signals, high yield and increased throughput. The main contribution here is validating adaptive strategies to overcome challenges in autonomous navigation of microelectrodes inside the brain. The following issues pose significant challenges as brain tissue is both functionally and structurally dynamic: a) time varying mechanical properties of the brain tissue-microelectrode interface due to the hyperelastic, viscoelastic nature of brain tissue b) non-stationarities in the neural signal caused by mechanical and physiological events in the interface and c) the lack of visual feedback of microelectrode position in brain tissue. A closed loop control algorithm is proposed here for autonomous navigation of microelectrodes in brain tissue while optimizing the signal-to-noise ratio of multi-unit neural recordings. The algorithm incorporates a quantitative understanding of constitutive mechanical properties of soft viscoelastic tissue like the brain and is guided by models that predict stresses developed in brain tissue during movement of the microelectrode. An optimal movement strategy is developed that achieves precise positioning of microelectrodes in the brain by minimizing the stresses developed in the surrounding tissue during navigation and maximizing the speed of movement. Results of testing the closed-loop control paradigm in short-term rodent experiments validated that it was possible to achieve a consistently high quality SNR throughout the duration of the experiment. At the systems level, new generation of MEMS actuators for movable microelectrode array are characterized and the MEMS device operation parameters are optimized for improved performance and reliability. Further, recommendations for packaging to minimize the form factor of the implant; design of device mounting and implantation techniques of MEMS microelectrode array to enhance the longevity of the implant are also included in a top-down approach to achieve a reliable brain interface.
Download or read book CMOS Biomicrosystems written by Krzysztof Iniewski and published by John Wiley & Sons. This book was released on 2011-10-14 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book will address the-state-of-the-art in integrated Bio-Microsystems that integrate microelectronics with fluidics, photonics, and mechanics. New exciting opportunities in emerging applications that will take system performance beyond offered by traditional CMOS based circuits are discussed in detail. The book is a must for anyone serious about microelectronics integration possibilities for future technologies. The book is written by top notch international experts in industry and academia. The intended audience is practicing engineers with electronics background that want to learn about integrated microsystems. The book will be also used as a recommended reading and supplementary material in graduate course curriculum.
Download or read book Hybrid NeuroMEMS written by Mohamad Hajj Hassan and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods for Neural Ensemble Recordings written by Miguel A. L. Nicolelis and published by CRC Press. This book was released on 2007-12-03 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extensively updated and expanded, this second edition of a bestseller distills the current state-of-the-science and provides the nuts and bolts foundation of the methods involved in this rapidly growing science. With contributions from pioneering researchers, it includes microwire array design for chronic neural recordings, new surgical techniques for chronic implantation, microelectrode microstimulation of brain tissue, multielectrode recordings in the somatosensory system and during learning, as well as recordings from the central gustatory-reward pathways. It explores the use of Brain-Machine Interface to restore neurological function and proposes conceptual and technical approaches to human neural ensemble recordings in the future.
Download or read book 3D System on package SoP Signal Generator to Control MEMS Movable Microelectrode Arrays written by Zikai Tee and published by . This book was released on 2012 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microelectrodes have been used as the neural interface to record brain's neural activities. Most of these electrodes are fixed positioned. Neural signal normally degrades over time due to the body immune response and brain micromotion that move the neurons away from the microelectrode. MEMS technology under SUMMiT VTM processes has developed miniaturized version of moveable microelectrodes that have the ability to recover the neural signal degradation by searching new cluster of neurons. To move the MEMS microelectrode a combination of four voltage waveforms must be applied to four thermally actuated microactuators. Previous design has used OmneticTM interconnect to transfer the waveforms from the external signal generators to the MEMS device. Unfortunately, the mechanism to attach and detach the OmneticTM interconnect introduce mechanical stress into the brain tissue that often caused raptures in the blood vessel. The goal of this project is to create an integrated System-On-Package Signal Generator that can be implanted on the brain of a rodent. A wireless system and a microcontroller are integrated together with the signal generators. The integrated system can be used to generate a series of voltage waveforms that can be customized to drive an array of MEMS movable microelectrodes when a triggered signal is received wirelessly. 3D stacking technique has been used to develop this Integrated System. 3D stacks lead to several favorable factors, such as (a) reduction in the power consumption of the system, (b) reduction in the overall form-factor of the package, and (c) significant reduction the weight of the package. There are a few challenges that must be overcome in this project, such as a commercially available microcontroller normally have an output voltage of 3.3 V to 5.5 V; however, a voltage of 7 - 8V is required to move the MEMS movable microelectrodes. To acquire higher density neural recording, more number of microelectrodes are needed. In this project, SoP Signal Generator is design to drive independently 3 moveable microelectrodes. Therefore, 12 voltage waveform are required. . However, the use of 12 signal generators is not a workable option since the system will be significantly large. This brings us to the other challenge, the limiting size of the rodent brain. Due to this factor, the SoP Signal Generator has to be deisgned to be able to fit without causing much pressure to the rodent's brain. For the first challenge, which is the limited output voltage of 3.3V on the microcontroller, the RC555 timers are used as an amplifier in addition to generating the signals. Demultiplexers have been for the next challenge, which is the need of 24 waveforms to drive 3 electrodes. For each waveform, 1 demultiplexer is used, making a total of 4 demultiplexers used in the entire system, which is a significant improvement from using 12 signal generators. The last challenge can be approached using 3D system stacking technique as mentioned above. The research aims of this project can be described as follows: (1) the testing and realization of the system part, and the designing of the system in a PCB level, (2) implementing and testing the SoP Signal Generator with the MEMS movable microelectrodes, The final outcome of this project can be used not only for neural applications, but also for more general applications that requires customized signal generations and wireless data transmission.
Download or read book Advanced MEMS Microprobes for Neural Stimulation and Recording written by Arash Akhavan Fomani and published by . This book was released on 2011 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: The in-vivo observation of the neural activities generated by a large number of closely located neurons is believed to be crucial for understanding the nervous system. Moreover, the functional electrical stimulation of the central nervous system is an effective method to restore physiological functions such as limb control, sound sensation, and light perception. The Deep Brain Stimulation (DBS) is being successfully used in the treatment of tremor and rigidity associated with advanced Parkinson's disease. Cochlear implants have also been employed as an effective treatment for sensorineural deafness by means of delivering the electrical stimulation directly to the auditory nerve. The most significant contribution of this PhD study is the development of next-generation microprobes for the simultaneous stimulation and recording of the cortex and deep brain structures. For intracortical applications, millimetre length multisite microprobes that are rigid enough to penetrate into the cortex while integrated with flexible interconnection cables are demanded. In chronic applications, the flexibility of the cable minimizes the tissue damage caused by the relative micro-motion between the brain and the microprobe. Although hybrid approaches have been reported to construct such neural microprobes, these devices are brittle and may impose severe complications if they break inside the tissue. In this project, MEMS fabrication processes were employed to produce non-breakable intracortical microprobes with an improved structural design. These 32 channel devices are integrated with flexible interconnection cables and provide enough mechanical strength for penetration into the tissue. Polyimide-based flexible implants were successfully fabricated and locally reinforced at the tip with embedded 15 [mu]m-thick gold micro-needles. In DBS applications, centimetre long microprobes capable of stimulating and recording the neural activity are required. The currently available DBS probes, manufactured by Medtronic, provide only four cylindrical shaped electrode sites, each 1.5 mm in height and 1.27 mm in diameter. Although suitable for the stimulation of a large brain volume, to measure the activity of a single neuron but to avoid measuring the average response of adjacent cells, recording sites with dimensions in the range of 10 - 20 [mu]m are required. In this work, novel Three Dimensional (3D) multi channel microprobes were fabricated offering 32 independent stimulation and recording electrodes around the shaft of the implant. These microprobes can control the spatial distribution of the charge injected into the tissue to enhance the efficacy and minimize the adverse effects of the DBS treatment. Furthermore, the device volume has been reduced to one third the volume of a conventional Medtronic DBS lead to significantly decrease the tissue damage induced by implantation of the microprobe. For both DBS and intracortical microprobes, the impedance characteristics of the electrodes were studied in acidic and saline solutions. To reduce the channel impedance and enhance the signal to noise ratio, iridium (Ir) was electroplated on gold electrode sites. Stable electrical characteristics were demonstrated for the Ir and gold electrodes over the course of a prolonged pulse stress test for 100 million cycles. The functionality and application potential of the fabricated microprobes were confirmed by the in-vitro measurements of the neural activity in the mouse hippocampus. In order to reduce the number of channels and simplify the signal processing circuitry, multiport electrostatic-actuated switch matrices were successfully developed, fabricated, and characterized for possible integration with neural microprobes to construct a site selection matrix. Magnetic-actuated switches have been also investigated to improve the operation reliability of the MEMS switching devices.
Download or read book Advances in Network Electrophysiology written by Makoto Taketani and published by Springer Science & Business Media. This book was released on 2006-11-22 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Network Electrophysiology: Using Multi Electrode Arrays explores methods for using electrophysiological techniques for monitoring the concurrent activity of ensembles of single neurons. It reviews the recent progress in both electronics and computational tools developed to analyze the functional operations of large ensembles of neurons using multi-electrode arrays and in vitro preparations. In addition, it gives readers a sense of the applications made possible by these technological tools. This volume is the reference for researchers, industry, graduate students, and postdoctoral fellows in all areas of neuroscience, cognitive neuroscience, pharmaceutical science, and bioengineering.
Download or read book Advanced MEMS Based Scalable Minimally Invasive 1024 Channel Microneedle and Subdural Brain and Spinal Cord Implants written by Sang Heon Lee and published by . This book was released on 2021 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neuromodulation devices are increasingly used in interrogating and treating neurological dysfunction in the human brain, spinal cord, and peripheral nerves. Recently, there has been an explosion of interest in applying these devices for brain-machine interfaces and advancing the state-of-the-art interface with the human brain. Toward this end, the Utah array has been the powerhouse of the BrainGate project that partially restored motor and sensory function to patients with neurological injury, though the array itself has advanced little in the last three decades. In this work, we leverage advanced dual-side lithographic microfabrication processes to demonstrate a 1024 channel penetrating Si microneedle array (SiMNA) that is scalable in its recording capabilities and cortical coverage. The SiMNA is built on flexible and transparent substrates permitting simultaneous optical and electrophysiological interrogation of the brain activity and is compliant to brain movements. We use the SiMNA to demonstrate reliable recordings of spontaneous and of evoked field potentials and of single unit activities in chronically implanted mice for up to 196 days in response to optogenetic and to whisker air-puff stimuli. Significantly, the 1024 channel SiMNA established detailed spatiotemporal mapping of broadband brain activity in rats. This novel scalable and biocompatible SiMNA with its multi-modal capability and sensitivity to broadband brain activity will accelerate our progress in fundamental neurophysiological investigations and establishes a new milestone for penetrating and large area coverage microelectrode arrays for brain-machine interfaces.The reach of soft substrates extends well beyond the curvilinear and pulsating brain toward spinal cord that relays the information bidirectionally to the brain and that has its own processing circuits for fundamental locomotion tasks. Materials that comprise of superior contact properties for recording and stimulation, that are minimally-invasive, and that are biocompatible and flexible have profound impact on the way we record and stimulate activity of the spinal cord. One important application of such devices is to aid in restoring function in spinal cord injury (SCI). However, thresholds for motor recruitment and for tissue damage during direct current stimulation in the spinal cord using recent microelectrode technologies are not yet established. Additionally, stimulation on the ventral side of the spinal cord in a closer proximity to the motor fibers is advantageous but systematic studies on the efficacy of microelectrode arrays for ventral stimulation versus dorsal stimulation and the stimulation parameters needed for initiation of motor response have not been studied before. This work reports the initiation thresholds for motor recruitment of rodent hindlimb from dorsal and ventral stimulation with various electrode sizes using a newly developed microelectrode material in our laboratory, the platinum nanorod (PtNR) contacts using two device configurations. Device type 1 comprises of microelectrodes of 9 diameters (40/60/80/100/120/140/160/180/200 [mu]m) and a macroelectrode of 250 [mu]m in diameter on sub-10 [mu]m thin flexible parylene-C substrate. Using Device type 1 in the acute setting for dorsal or ventral-lateral spinal cord implantation and electrical stimulation in rats, we quantified lower current thresholds and charge densities, and a lower critical diameter for evoking responses in the sciatic nerves and electromyography responses in hindlimb muscles. Device type 2 consists of three representative diameters (40/100/200 [mu]m) of PtNR electrodes from Device type 1 on sub-10 [mu]m thin flexible polyimide substrate for investigating the stability of the platform on semi-chronic rat implants accompanied by a rigorous stimulation paradigm with a total of over 1 million pulse pairs. This stimulation paradigm is designed based on the a 7-hour stimulation session initially implemented by McCreery et al. In our work, we used a much higher pulse frequency of ~ 200 Hz over the duration of 84 minutes doubling the amount of charge used in McCreery et al.'s work. Device type 3 consists of 128 channels (4 × 32 array) of PtNR electrodes with 30 [mu]m diameter on sub-10 [mu]m thin flexible parylene-C substrate which was used to detect spatiotemporal compound action potentials (CAP) from an acute pig model and demonstrate the high scalability of the device platform.
Download or read book Neural Interfacing written by Thomas D. Coates and published by Morgan & Claypool Publishers. This book was released on 2008 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past 50 years there has been an explosion of interest in the development of technologies whose end goal is to connect the human brain and/or nervous system directly to computers. Once the subject of science fiction, the technologies necessary to accomplish this goal are rapidly becoming reality. In laboratories around the globe, research is being undertaken to restore function to the physically disabled, to replace areas of the brain damaged by disease or trauma and to augment human abilities. Building neural interfaces and neuro-prosthetics relies on a diverse array of disciplines such as neuroscience, engineering, medicine and microfabrication just to name a few. This book presents a short history of neural interfacing (N.I.) research and introduces the reader to some of the current efforts to develop neural prostheses. The book is intended as an introduction for the college freshman or others wishing to learn more about the field. A resource guide is included for students along with a list of laboratories conducting N.I. research and universities with N.I. related tracks of study. Table of Contents: Neural Interfaces Past and Present / Current Neuroprosthesis Research / Conclusion / Resources for Students
Download or read book Mechanistic Electrochemical Characterization of Novel Microelectrode Arrays and Their Application in Mapping Brain Activity Across Species and Humans written by Mehran Ganji and published by . This book was released on 2019 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrocorticography (ECoG) arrays are used in clinical mapping for neurosurgical resection and hold the promise for less damaging brain-machine interfaces. Current clinical ECoG electrodes face physical limits to the number of contact sites, spatial resolution (centimeter scale), and contact diameter (millimeter scale), and thus cannot resolve the dynamically changing neural activity over sub-millimeter scales . In addition to these practical limitations, current clinical electrode arrays are constrained to non-conformal electrode-carriers/substrates and to less-optimal metal electrochemical interfaces. Increasing the flexibility of clinical electrodes may lead to higher signal-to-noise ratios as well as higher spatial specificity and this also requires overcoming substantial physical barriers due to the compromised metal electrochemical interface properties. The objectives of this thesis, described in seven chapters, are to develop high performance, safe, and durable neural electrode interfaces to yield stable, high signal-to-noise ratio cortical recordings in animal models as well as in humans. In the second chapter, we demonstrate that sterilization of PEDOT:PSS electrophysiology devices can be performed using an autoclave. We find that autoclaving is a viable sterilization method, leaving morphology unaltered and causing only minor changes in electrical properties. These results pave the way for the widespread utilization of PEDOT:PSS electrophysiology devices in the clinic. In the third chapter, we translate the use of robust PEDOT:PSS microelectrode arrays for safe intraoperative monitoring of the human brain. PEDOT:PSS micro-electrodes measured significant differential neural modulation under various clinically relevant conditions. We report the first evoked (stimulus-locked) cognitive activity with changes in amplitude across pial surface distances as small as 400 [mu]m, potentially enabling basic neurophysiology studies at the scale of neural micro-circuitry. In the fourth and fifth chapters, we present the first systematic study of scaling effects on the electrochemical properties of Pt and Au metallic and PEDOT:PSS organic electrodes from neural recording and stimulation perspectives. PEDOT:PSS coating reduced the impedances of metallic electrodes by up to 18X. The overall reduced noise of the PEDOT:PSS microelectrodes enable a lower noise floor for recording action-potentials with high fidelity. We observed a substantial enhancement in charge injection capacity up to 9.5X for PEDOT:PSS microelectrodes compared to metal ones and 88% lower required power for injecting the same charge density. These results permit quantitative optimization of contact material and diameter for different ECoG applications. In the sixth chapter, We report an effective method of mechanically anchoring the PEDOT within the Au nanorod (Au-nr) structure and demonstrate that it provides enhanced adhesion and overall PEDOT layer stability under various electrochemical (charge injection) and In vivo stability tests. In the seventh chapter, we report the fabrication of pure Pt nanorods (PtNRs) by utilizing low-temperature selective dealloying to develop scalable and biocompatible 1D platinum nanorod (PtNR) arrays that exhibit superb electrochemical properties at various length scales for high-performance neurotechnologies. PtNR arrays record brain activity with cellular resolution from the cortical surfaces in birds, mice, and non-human primates; demonstrating the PtNR microelectrode system as a robust system for high performance and stable neural electrode interfaces.
Download or read book Biomedical Microsystems written by Ellis Meng and published by CRC Press. This book was released on 2011-06-22 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Poised to dramatically impact human health, biomedical microsystems (bioMEMS) technologies incorporate various aspects from materials science, biology, chemistry, physics, medicine, and engineering. Reflecting the highly interdisciplinary nature of this area, Biomedical Microsystems covers the fundamentals of miniaturization, biomaterials, microfabrication, and nanotechnology, along with relevant applications. Written by an active researcher who was recently named one of Technology Review’s Young Innovators Under 35, the book begins with an introduction to the benefits of miniaturization. It then introduces materials, fabrication technology, and the necessary components of all bioMEMS. The author also covers fundamental principles and building blocks, including microfluidic concepts, lab-on-a-chip systems, and sensing and detection methods. The final chapters explore several important applications of bioMEMS, such as microdialysis, catheter-based sensors, MEMS implants, neural probes, and tissue engineering. For readers with a limited background in MEMS and bioMEMS, this book provides a practical introduction to the technology used to make these devices, the principles that govern their operation, and examples of their application. It offers a starting point for understanding advanced topics and encourages readers to begin to formulate their own ideas about the design of novel bioMEMS. A solutions manual is available for instructors who want to convert this reference to classroom use.
Download or read book Neural Microelectrodes written by Stuart F. Cogan and published by Mdpi AG. This book was released on 2019-08-12 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neural electrodes enable the recording and stimulation of bioelectrical activity in the nervous system. This technology provides neuroscientists with the means to probe the functionality of neural circuitry in both health and disease. In addition, neural electrodes can deliver therapeutic stimulation for the relief of debilitating symptoms associated with neurological disorders such as Parkinson's disease and may serve as the basis for the restoration of sensory perception through peripheral nerve and brain regions after disease or injury. Lastly, microscale neural electrodes recording signals associated with volitional movement in paralyzed individuals can be decoded for controlling external devices and prosthetic limbs or driving the stimulation of paralyzed muscles for functional movements. In spite of the promise of neural electrodes for a range of applications, chronic performance remains a goal for long-term basic science studies, as well as clinical applications. New perspectives and opportunities from fields including tissue biomechanics, materials science, and biological mechanisms of inflammation and neurodegeneration are critical to advances in neural electrode technology. This Special Issue will address the state-of-the-art knowledge and emerging opportunities for the development and demonstration of advanced neural electrodes.
Download or read book PEDOT PSS Parylene C ECoG Microelectrode Arrays for Multi Modal Recording of Brain Activity in Birds and Rodents written by Lorraine Amena Hossain and published by . This book was released on 2020 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding cognitive processing in intact brains is the subject of intense research efforts that aim to resolve individual and network activity of neuronal cells across different layers of the brain. While efforts to record a large number of individual cellular activity in intact brains are underway, the network-level coordinated activity of neurons result in long-range, low frequency oscillations that carry significant electrophysiological information and is the gold standard for recording neural correlates of cognition from animals and humans. Recently, recording of individual cellular activity, commonly referred to as single units, with high signal-to-noise ratio from the cortical surface was accomplished. Critical to this milestone in electrophysiology was the use of organic microelectrode arrays that (1) possess superior electrochemical junction characteristics enabling them to have contact diameters that are similar to neuronal sizes yet while maintaining low electrochemical impedances and low noise, and (2) enable conformal coverage of thin parylene C device carrier layers to the brain curvature. The small contact diameter, and therefore listening sphere, its low noise, and its intimate contact with the surface of the brain are all attributed as essential conditions to permit the recording of single unit activity from the brain's surface. This thesis appraises the development of novel microelectrode arrays that record single units from the brain's surface, and their application in recording brain activity from anesthetized and awake animal models. The first part of the dissertation discusses the application of Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, commonly known as PEDOT:PSS--a semiconductive polymer with excellent electrochemical properties--as well as microelectrode contacts that employ large surface area one-dimensional nanostructures, to the electrophysiological investigations in songbird experiments. Significantly, we observed strong correlation of surface-recorded single units with spectrotemporal features of replayed birdsongs across trials and that were also validated with simultaneously implanted depth electrodes. This finding has implications for minimally destructive brain-machine interfaces that can make use of surface-recorded units. Additionally, we carried out systematic investigations to understand the influence of the electrode contact diameter and the contact material on resolving single unit activity from the surface of the brain. Our initial results suggest that contacts with lower impedances result in higher signal amplitude as well as higher biological noise amplitude, due to their sensitivity and that amplitude of single units generally decreases with diameter. While acute recordings can streamline testing of neurotechnologies, chronic recordings are important for applications in which subjects can ultimately engage in behavioral experiments. To this end, the last part of this dissertation concerns with the development and optimization of a chronically stable device form factor. This device leverages the transparency of the parylene C substrate to perform simultaneous electrophysiological recording and multi-photon imaging of neuronal activity in awake mice. We recorded stimulus-evoked calcium indicator responses that correlated with local field potential (LFP) response and higher frequency multi- and single unit activity. This dissertation encompasses advances in the scalable, monolithic fabrication procedure for high-yield PEDOT:PSS microelectrode arrays on parylene C substrates and their utility of electrocorticography (ECoG) recording capability of neuronal activity from intact brains.
Download or read book Augmentation of Brain Function Facts Fiction and Controversy written by Ioan Opris and published by Frontiers Media SA. This book was released on 2018-09-14 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Volume II is entitled “Neurostimulation and pharmacological approaches”. This volume describes augmentation approaches, where improvements in brain functions are achieved by modulation of brain circuits with electrical or optical stimulation, or pharmacological agents. Activation of brain circuits with electrical currents is a conventional approach that includes such methods as (i) intracortical microstimulation (ICMS), (ii) transcranial direct current stimulation (tDCS), and (iii) transcranial magnetic stimulation (TMS). tDCS and TMS are often regarded as noninvasive methods. Yet, they may induce long-lasting plastic changes in the brain. This is why some authors consider the term “noninvasive” misleading when used to describe these and other techniques, such as stimulation with transcranial lasers. The volume further discusses the potential of neurostimulation as a research tool in the studies of perception, cognition and behavior. Additionally, a notion is expressed that brain augmentation with stimulation cannot be described as a net zero sum proposition, where brain resources are reallocated in such a way that gains in one function are balanced by costs elsewhere. In recent years, optogenetic methods have received an increased attention, and several articles in Volume II cover different aspects of this technique. While new optogenetic methods are being developed, the classical electrical stimulation has already been utilized in many clinically relevant applications, like the vestibular implant and tactile neuroprosthesis that utilizes ICMS. As a peculiar usage of neurostimulation and pharmacological methods, Volume II includes several articles on augmented memory. Memory prostheses are a popular recent development in the stimulation-based BMIs. For example, in a hippocampal memory prosthesis, memory content is extracted from hippocampal activity using a multiple-input, multiple-output non-linear dynamical model. As to the pharmacological approaches to augmenting memory and cognition, the pros and cons of using nootropic drugs are discussed.
Download or read book Neural Computation Neural Devices and Neural Prosthesis written by Zhi Yang and published by Springer Science & Business Media. This book was released on 2014-04-15 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decades, interdisciplinary investigations overlapping biology, medicine, information science, and engineering have formed a very exciting and active field that attracts scientists, medical doctors, and engineers with knowledge in different domains. A few examples of such investigations include neural prosthetic implants that aim to improve the quality of life for patients suffering from neurologic disease and injury; brain machine interfaces that sense, analyze, and translate electrical signals from the brain to build closed-loop, biofeedback systems; and fundamental studies of intelligence, cognitive functions, and psychological behaviors correlated to their neurological basis. Although this interdisciplinary area is still in its infancy, it can potentially create some of the most significant impact: treating diseases that are considered untreatable, interpretation and communication of neuron ensembles, or even a revolutionary perception and understanding of life different from philosophical or immaterial approaches. Fortunately, several academic societies recognize the value and impact of this growing field, firmly supporting related research. Such support will drive a booming future in the next twenty or thirty years. Research in this area is frequently project-driven, and the generated knowledge has been scattered in different fields of neuroscience, computation, material and technology, circuits and system, clinical reports, and psychology—the scope considerably across the boundary of traditionally defined disciplines. Neural Computation, Neural Devices, and Neural Prosthesis is intended to assemble such knowledge, from there suggesting a systematic approach guiding future educational and research activities. The targeted audience includes both students and researchers.
Download or read book Development of Flexible Electrode Arrays for Chronic Stable and Scalable Neural Recording written by Zhengtuo Zhao and published by . This book was released on 2019 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: The brain is a massively-interconnected and constantly-evolving network of specialized circuits; a systematic understanding of the circuits requires a probe-tissue interface that can record and modulate brain activities at diverse spatial and temporal scales. Implanted electrodes provide a unique approach to decipher brain circuitry by allowing for time-resolved electrical detection of individual neuron activity. However, conventional intracortical recordings are often sparse, and importantly, unstable over long term. These pose limitations on their scientific and clinical applications. Through the use of less-rigid polymer materials and the ten-to-a-hundred fold reduction on probe size, the flexibility of a neural probe can be improved by four orders of magnitude, which results in a friendly probe-tissue interfaces, long-term recording performance, and greater potential for scaling up in implantation density. Here we present our progress on the development of a novel neural recording platform including 1. A stable neural interface named nanoelectronic threads (NETs) which demonstrated long-term stable recording over four months, seamless chronic probe-tissue integration and easy compatibility with optical imaging. 2. A facile implantation method to apply the flexible NETs in scalable, reliable neural recording in rodent brain. 3. A dense and high-bandwidth NET platform towards volumetric mapping and large-scale distributed recordings in the neocortex and subcortical structures, and 4. A low-cost and versatile multifunctional neural probe platform to achieve optogenetic stimulation and controlled drug infusion with simultaneous, spatially resolved neural recording. These capabilities will drive new long-term studies of brain circuits across different spatiotemporal dimensions and modalities
