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https://www.readbyqxmd.com/read/28539421/sound-making-actions-lead-to-immediate-plastic-changes-of-neuromagnetic-evoked-responses-and-induced-beta-band-oscillations-during-perception
#1
Bernhard Ross, Masihullah Barat, Takako Fujioka
Auditory and sensorimotor brain areas interact during the action-perception cycle of sound making. Neurophysiological evidence of a feedforward model of the action and its outcome has been associated with attenuation of the N1 wave of auditory evoked responses elicited by self-generated sounds, such as vocalization or playing a musical instrument. Moreover, neural oscillations at beta-band frequencies have been related to predicting the sound outcome after action initiation. We hypothesized that a newly learned action-perception association would immediately modify interpretation of the sound during subsequent listening...
May 24, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28534804/fuzzy-adaptive-decentralized-optimal-control-for-strict-feedback-nonlinear-large-scale-systems
#2
Kangkang Sun, Shuai Sui, Shaocheng Tong
This paper considers the optimal decentralized fuzzy adaptive control design problem for a class of interconnected large-scale nonlinear systems in strict feedback form and with unknown nonlinear functions. The fuzzy logic systems are introduced to learn the unknown dynamics and cost functions, respectively, and a state estimator is developed. By applying the state estimator and the backstepping recursive design algorithm, a decentralized feedforward controller is established. By using the backstepping decentralized feedforward control scheme, the considered interconnected large-scale nonlinear system in strict feedback form is changed into an equivalent affine large-scale nonlinear system...
May 16, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/28521606/can-video-self-modeling-improve-affected-limb-reach-and-grasp-ability-in-stroke-patients
#3
Kylie Ann Steel, Kurt Mudie, Remi Sandoval, David Anderson, Sera Dogramaci, Mohammad Rehmanjan, Ingvars Birznieks
The authors examined whether feedforward video self-modeling (FF VSM) would improve control over the affected limb, movement self-confidence, movement self-consciousness, and well-being in 18 stroke survivors. Participants completed a cup transport task and 2 questionnaires related to psychological processes pre- and postintervention. Pretest video footage of the unaffected limb performing the task was edited to create a best-of or mirror-reversed training DVD, creating the illusion that patients were performing proficiently with the affected limb...
May 19, 2017: Journal of Motor Behavior
https://www.readbyqxmd.com/read/28495545/asymptotic-tracking-and-disturbance-rejection-of-the-blood-glucose-regulation-system
#4
Brandon Ashley, Weijiu Liu
Type 1 diabetes patients need external insulin to maintain blood glucose within a narrow range from 65 to 108 mg/dl (3.6 to 6.0 mmol/l). A mathematical model for the blood glucose regulation is required for integrating a glucose monitoring system into insulin pump technology to form a closed-loop insulin delivery system on the feedback of the blood glucose, the so-called "artificial pancreas". The objective of this paper is to treat the exogenous glucose from food as a glucose disturbance and then develop a closed-loop feedback and feedforward control system for the blood glucose regulation system subject to the exogenous glucose disturbance...
May 8, 2017: Mathematical Biosciences
https://www.readbyqxmd.com/read/28485414/systematic-comparison-of-the-response-properties-of-protein-and-rna-mediated-gene-regulatory-motifs
#5
Bharat Ravi Iyengar, Beena Pillai, K V Venkatesh, Chetan J Gadgil
We present a framework enabling the dissection of the effects of motif structure (feedback or feedforward), the nature of the controller (RNA or protein), and the regulation mode (transcriptional, post-transcriptional or translational) on the response to a step change in the input. We have used a common model framework for gene expression where both motif structures have an activating input and repressing regulator, with the same set of parameters, to enable a comparison of the responses. We studied the global sensitivity of the system properties, such as steady-state gain, overshoot, peak time, and peak duration, to parameters...
May 9, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28466892/the-multi-output-incoherent-feedforward-loop-constituted-by-the-transcriptional-regulators-lasr-and-rsal-confers-robustness-to-a-subset-of-quorum-sensing-genes-in-pseudomonas-aeruginosa
#6
Roslen Bondí, Francesca Longo, Marco Messina, Francesca D'Angelo, Paolo Visca, Livia Leoni, Giordano Rampioni
Quorum sensing (QS) is an intercellular communication system which controls virulence-related phenotypes in the human pathogen Pseudomonas aeruginosa. LasR is the QS receptor protein which responds to the signal molecule N-(3-oxododecanoyl)homoserine lactone (3OC12-HSL) and promotes signal production by increasing the transcription of the 3OC12-HSL synthase gene, lasI. LasR also activates the expression of other genes, including rsaL, coding for the RsaL protein which acts as a transcriptional repressor of lasI...
May 3, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28463330/improving-the-performance-of-interferometric-imaging-through-the-use-of-disturbance-feedforward
#7
Michael Böhm, Martin Glück, Alexander Keck, Jörg-Uwe Pott, Oliver Sawodny
In this paper, we present a disturbance compensation technique to improve the performance of interferometric imaging for extremely large ground-based telescopes, e.g., the Large Binocular Telescope (LBT), which serves as the application example in this contribution. The most significant disturbance sources at ground-based telescopes are wind-induced mechanical vibrations in the range of 8-60 Hz. Traditionally, their optical effect is eliminated by feedback systems, such as the adaptive optics control loop combined with a fringe tracking system within the interferometric instrument...
May 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/28449714/detecting-central-fixation-by-means-of-artificial-neural-networks-in-a-pediatric-vision-screener-using-retinal-birefringence-scanning
#8
Boris I Gramatikov
BACKGROUND: Reliable detection of central fixation and eye alignment is essential in the diagnosis of amblyopia ("lazy eye"), which can lead to blindness. Our lab has developed and reported earlier a pediatric vision screener that performs scanning of the retina around the fovea and analyzes changes in the polarization state of light as the scan progresses. Depending on the direction of gaze and the instrument design, the screener produces several signal frequencies that can be utilized in the detection of central fixation...
April 27, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28428010/a-strategy-of-faster-movements-used-by-elderly-humans-to-lift-objects-of-increasing-weight-in-ecological-context
#9
Thomas Hoellinger, Joseph McIntyre, Lena Jami, Sylvain Hanneton, Guy Cheron, Agnes Roby-Brami
It is not known whether, during the course of ageing, changes occur in the motor strategies used by the CNS for lifting objects of different weights. Here, we analysed the kinematics of object-lifting in two different healthy groups (young and elderly people) plus one well known deafferented patient (GL). The task was to reach and lift onto a shelf an opaque cylindrical object with changing weight. The movements of the hand and object were recorded with electromagnetic sensors. In an ecological context (i.e...
April 17, 2017: Neuroscience
https://www.readbyqxmd.com/read/28414802/neuronal-cell-fate-specification-by-the-molecular-convergence-of-different-spatio-temporal-cues-on-a-common-initiator-terminal-selector-gene
#10
Johannes Stratmann, Stefan Thor
The extensive genetic regulatory flows underlying specification of different neuronal subtypes are not well understood at the molecular level. The Nplp1 neuropeptide neurons in the developing Drosophila nerve cord belong to two sub-classes; Tv1 and dAp neurons, generated by two distinct progenitors. Nplp1 neurons are specified by spatial cues; the Hox homeotic network and GATA factor grn, and temporal cues; the hb -> Kr -> Pdm -> cas -> grh temporal cascade. These spatio-temporal cues combine into two distinct codes; one for Tv1 and one for dAp neurons that activate a common terminal selector feedforward cascade of col -> ap/eya -> dimm -> Nplp1...
April 2017: PLoS Genetics
https://www.readbyqxmd.com/read/28413823/long-term-predictive-and-feedback-encoding-of-motor-signals-in-the-simple-spike-discharge-of-purkinje-cells
#11
Laurentiu S Popa, Martha L Streng, Timothy J Ebner
Most hypotheses of cerebellar function emphasize a role in real-time control of movements. However, the cerebellum's use of current information to adjust future movements and its involvement in sequencing, working memory, and attention argues for predicting and maintaining information over extended time windows. The present study examines the time course of Purkinje cell discharge modulation in the monkey (Macaca mulatta) during manual, pseudo-random tracking. Analysis of the simple spike firing from 183 Purkinje cells during tracking reveals modulation up to 2 s before and after kinematics and position error...
March 2017: ENeuro
https://www.readbyqxmd.com/read/28398244/piezoelectric-actuated-phase-shifter-based-on-external-laser-interferometer-design-control-and-experimental-validation
#12
Peng-Zhi Li, Xiao-Dong Wang, Yong-Xin Sui, De-Fu Zhang, Dong-Fang Wang, Li-Jian Dong, Ming-Yang Ni
To improve the phase-shifting accuracy, this paper presents a novel integrated framework for design, control and experimental validation of the piezoelectric actuated phase shifter with a trade-off between accuracy and cost. The piezoelectric actuators with built-in sensors are adopted to drive the double parallel four-bar linkage flexure hinge-based mechanisms. Three mechanisms form the tripod structure of the assembled phase shifter. Then, a semi-closed loop controller with inner feedback and outer feedforward loops via the external laser interferometer is developed for accurate positioning of the phase shifter...
April 11, 2017: Sensors
https://www.readbyqxmd.com/read/28392606/design-of-an-embedded-inverse-feedforward-biomolecular-tracking-controller-for-enzymatic-reaction-processes
#13
Mathias Foo, Jongrae Kim, Rucha Sawlekar, Declan G Bates
Feedback control is widely used in chemical engineering to improve the performance and robustness of chemical processes. Feedback controllers require a 'subtractor' that is able to compute the error between the process output and the reference signal. In the case of embedded biomolecular control circuits, subtractors designed using standard chemical reaction network theory can only realise one-sided subtraction, rendering standard controller design approaches inadequate. Here, we show how a biomolecular controller that allows tracking of required changes in the outputs of enzymatic reaction processes can be designed and implemented within the framework of chemical reaction network theory...
April 6, 2017: Computers & Chemical Engineering
https://www.readbyqxmd.com/read/28386448/elasticity-improves-handgrip-performance-and-user-experience-during-visuomotor-control
#14
Michael Mace, Paul Rinne, Jean-Luc Liardon, Catherine Uhomoibhi, Paul Bentley, Etienne Burdet
Passive rehabilitation devices, providing motivation and feedback, potentially offer an automated and low-cost therapy method, and can be used as simple human-machine interfaces. Here, we ask whether there is any advantage for a hand-training device to be elastic, as opposed to rigid, in terms of performance and preference. To address this question, we have developed a highly sensitive and portable digital handgrip, promoting independent and repetitive rehabilitation of grasp function based around a novel elastic force and position sensing structure...
February 2017: Royal Society Open Science
https://www.readbyqxmd.com/read/28367561/cancerous-perturbations-within-the-erk-pi3k-akt-and-wnt-%C3%AE-catenin-signaling-network-constitutively-activate-inter-pathway-positive-feedback-loops
#15
Rahul Rao Padala, Rishabh Karnawat, Satish Bharathwaj Viswanathan, Abhishek Vijay Thakkar, Asim Bikas Das
Perturbations in molecular signaling pathways are a result of genetic or epigenetic alterations, which may lead to malignant transformation of cells. Despite cellular robustness, specific genetic or epigenetic changes of any gene can trigger a cascade of failures, which result in the malfunctioning of cell signaling pathways and lead to cancer phenotypes. The extent of cellular robustness has a link with the architecture of the network such as feedback and feedforward loops. Perturbation in components within feedback loops causes a transition from a regulated to a persistently activated state and results in uncontrolled cell growth...
May 2, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28355147/glimpse-google-glass-interface-for-sensory-feedback-in-myoelectric-hand-prostheses
#16
Marko Markovic, Hemanth Karnal, Bernhard Graimann, Dario Farina, Strahinja Dosen
OBJECTIVE: Providing sensory feedback to the user of the prosthesis is an important challenge. The common approach is to use tactile stimulation, which is easy to implement but requires training and has limited information bandwidth. In this study, we propose an alternative approach based on augmented reality. APPROACH: We have developed the GLIMPSE, a Google Glass application which connects to the prosthesis via a Bluetooth interface and renders the prosthesis states (EMG signals, aperture, force and contact) using augmented reality (see-through display) and sound (bone conduction transducer)...
June 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/28351197/the-human-central-pattern-generator-for-locomotion
#17
Karen Minassian, Ursula S Hofstoetter, Florin Dzeladini, Pierre A Guertin, Auke Ijspeert
The ability of dedicated spinal circuits, referred to as central pattern generators (CPGs), to produce the basic rhythm and neural activation patterns underlying locomotion can be demonstrated under specific experimental conditions in reduced animal preparations. The existence of CPGs in humans is a matter of debate. Equally elusive is the contribution of CPGs to normal bipedal locomotion. To address these points, we focus on human studies that utilized spinal cord stimulation or pharmacological neuromodulation to generate rhythmic activity in individuals with spinal cord injury, and on neuromechanical modeling of human locomotion...
March 1, 2017: Neuroscientist: a Review Journal Bringing Neurobiology, Neurology and Psychiatry
https://www.readbyqxmd.com/read/28350336/sensor-fault-and-delay-tolerant-control-for-networked-control-systems-subject-to-external-disturbances
#18
Shi-Yuan Han, Yue-Hui Chen, Gong-You Tang
In this paper, the problem of sensor fault and delay tolerant control problem for a class of networked control systems under external disturbances is investigated. More precisely, the dynamic characteristics of the external disturbance and sensor fault are described as the output of exogenous systems first. The original sensor fault and delay tolerant control problem is reformulated as an equivalence problem with designed available system output and reformed performance index. The feedforward and feedback sensor fault tolerant controller (FFSFTC) can be obtained by utilizing the solutions of Riccati matrix equation and Stein matrix equation...
March 28, 2017: Sensors
https://www.readbyqxmd.com/read/28348530/paradigm-shifts-in-voluntary-force-control-and-motor-unit-behaviors-with-the-manipulated-size-of-visual-error-perception
#19
Yi-Ching Chen, Yen-Ting Lin, Gwo-Ching Chang, Ing-Shiou Hwang
The detection of error information is an essential prerequisite of a feedback-based movement. This study investigated the differential behavior and neurophysiological mechanisms of a cyclic force-tracking task using error-reducing and error-enhancing feedback. The discharge patterns of a relatively large number of motor units (MUs) were assessed with custom-designed multi-channel surface electromyography following mathematical decomposition of the experimentally-measured signals. Force characteristics, force-discharge relation, and phase-locking cortical activities in the contralateral motor cortex to individual MUs were contrasted among the low (LSF), normal (NSF), and high scaling factor (HSF) conditions, in which the sizes of online execution errors were displayed with various amplification ratios...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28341164/expectation-violation-and-attention-to-pain-jointly-modulate-neural-gain-in-somatosensory-cortex
#20
Francesca Fardo, Ryszard Auksztulewicz, Micah Allen, Martin J Dietz, Andreas Roepstorff, Karl J Friston
The neural processing and experience of pain are influenced by both expectations and attention. For example, the amplitude of event-related pain responses is enhanced by both novel and unexpected pain, and by moving the focus of attention towards a painful stimulus. Under predictive coding, this congruence can be explained by appeal to a precision-weighting mechanism, which mediates bottom-up and top-down attentional processes by modulating the influence of feedforward and feedback signals throughout the cortical hierarchy...
March 21, 2017: NeuroImage
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