keyword
MENU ▼
Read by QxMD icon Read
search

dynamic neural field

keyword
https://www.readbyqxmd.com/read/29053865/beta-burst-dynamics-in-parkinson-s-disease-off-and-on-dopaminergic-medication
#1
Gerd Tinkhauser, Alek Pogosyan, Huiling Tan, Damian M Herz, Andrea A Kühn, Peter Brown
Exaggerated basal ganglia beta activity (13-35 Hz) is commonly found in patients with Parkinson's disease and can be suppressed by dopaminergic medication, with the degree of suppression being correlated with the improvement in motor symptoms. Importantly, beta activity is not continuously elevated, but fluctuates to give beta bursts. The percentage number of longer beta bursts in a given interval is positively correlated with clinical impairment in Parkinson's disease patients. Here we determine whether the characteristics of beta bursts are dependent on dopaminergic state...
October 10, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/29051496/evidence-for-a-task-dependent-switch-in-subthalamo-nigral-basal-ganglia-signaling
#2
Jay J Jantz, Masayuki Watanabe, Ron Levy, Douglas P Munoz
Basal ganglia (BG) can either facilitate or inhibit movement through excitatory and inhibitory pathways; however whether these opposing signals are dynamically regulated during healthy behavior is not known. Here, we present compelling neurophysiological evidence from three complimentary experiments in non-human primates, indicating task-specific changes in tonic BG pathway weightings during saccade behavior with different cognitive demands. First, simultaneous local field potential recording in the subthalamic nucleus (STN; BG input) and substantia nigra pars reticulata (SNr; BG output) reveals task-dependent shifts in subthalamo-nigral signals...
October 19, 2017: Nature Communications
https://www.readbyqxmd.com/read/29050909/bold-fmri-in-the-mouse-auditory-pathway
#3
Guilherme Blazquez Freches, Cristina Chavarrias, Noam Shemesh
The auditory pathway is widely distributed throughout the brain, and is perhaps one of the most interesting networks in the context of neuroplasticity. Accurate mapping of neural activity in the entire pathway, preferably noninvasively, and with high resolution, could be instrumental for understanding such longitudinal processes. Functional magnetic resonance imaging (fMRI) has clear advantages for such characterizations, as it is noninvasive, provides relatively high spatial resolution and lends itself for repetitive studies, albeit relying on an indirect neurovascular coupling to deliver its information...
October 16, 2017: NeuroImage
https://www.readbyqxmd.com/read/29040412/random-recurrent-networks-near-criticality-capture-the-broadband-power-distribution-of-human-ecog-dynamics
#4
Rishidev Chaudhuri, Biyu J He, Xiao-Jing Wang
Brain electric field potentials are dominated by an arrhythmic broadband signal, but the underlying mechanism is poorly understood. Here we propose that broadband power spectra characterize recurrent neural networks of nodes (neurons or clusters of neurons), endowed with an effective balance between excitation and inhibition tuned to keep the network on the edge of dynamical instability. These networks show a fast mode reflecting local dynamics and a slow mode emerging from distributed recurrent connections...
October 13, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/29031703/comparative-approximations-of-criticality-in-a-neural-and-quantum-regime
#5
REVIEW
Jesse Sterling Bettinger
Under a variety of conditions, non-linear systems with many degrees of freedom tend to evolve towards complexity and criticality. Over the last few decades, a steady proliferation of models re: nonlinear and far-from-equilibrium thermodynamics of metastable, many-valued systems arose, serving as attributes of a 'critical' attractor landscape. Building off recent data citing trademark aspects of criticality in the brain-including: power-laws, scale-free (1/f) behavior (scale invariance, or scale independence, critical slowing, and avalanches-it has been conjectured that operating at criticality entails functional advantages such as: optimized neural computation and information processing; memory; large dynamical ranges; long-range communication; and "enhanced ability to react to highly diverse stimuli...
October 11, 2017: Progress in Biophysics and Molecular Biology
https://www.readbyqxmd.com/read/29017140/lifelong-learning-of-human-actions-with-deep-neural-network-self-organization
#6
German I Parisi, Jun Tani, Cornelius Weber, Stefan Wermter
Lifelong learning is fundamental in autonomous robotics for the acquisition and fine-tuning of knowledge through experience. However, conventional deep neural models for action recognition from videos do not account for lifelong learning but rather learn a batch of training data with a predefined number of action classes and samples. Thus, there is the need to develop learning systems with the ability to incrementally process available perceptual cues and to adapt their responses over time. We propose a self-organizing neural architecture for incrementally learning to classify human actions from video sequences...
September 20, 2017: Neural Networks: the Official Journal of the International Neural Network Society
https://www.readbyqxmd.com/read/28988134/dynamics-of-large-scale-electrophysiological-networks-a-technical-review
#7
REVIEW
George C O'Neill, Prejaas Tewarie, Diego Vidaurre, Lucrezia Liuzzi, Mark W Woolrich, Matthew J Brookes
For several years it has been argued that neural synchronisation is crucial for cognition. The idea that synchronised temporal patterns between different neural groups carries information above and beyond the isolated activity of these groups has inspired a shift in focus in the field of functional neuroimaging. Specifically, investigation into the activation elicited within certain regions by some stimulus or task has, in part, given way to analysis of patterns of co-activation or functional connectivity between distal regions...
October 4, 2017: NeuroImage
https://www.readbyqxmd.com/read/28985928/methods-and-considerations-for-dynamic-analysis-of-functional-mr-imaging-data
#8
REVIEW
Jingyuan E Chen, Mikail Rubinov, Catie Chang
Functional MR imaging (fMR imaging) studies have recently begun to examine spontaneous changes in interregional interactions (functional connectivity) over seconds to minutes, and their relation to natural shifts in cognitive and physiologic states. This practice opens the potential for uncovering structured, transient configurations of coordinated brain activity whose features may provide novel cognitive and clinical biomarkers. However, analysis of these time-varying phenomena requires careful differentiation between neural and nonneural contributions to the fMR imaging signal and thorough validation and statistical testing...
November 2017: Neuroimaging Clinics of North America
https://www.readbyqxmd.com/read/28981613/-wrong-way-up-temporal-and-spatial-dynamics-of-the-networks-for-body-motion-processing-at-9-4-t
#9
Marina A Pavlova, Michael Erb, Gisela E Hagberg, Joana Loureiro, Alexander N Sokolov, Klaus Scheffler
Body motion delivers a wealth of socially relevant information. Yet display inversion severely impedes biological motion (BM) processing. It is largely unknown how the brain circuits for BM are affected by display inversion. As upright and upside-down point-light BM displays are similar, we addressed this issue by using ultrahigh field functional MRI at 9.4 T providing for high sensitivity and spatial resolution. Whole-brain analysis along with exploration of the temporal dynamics of the blood-oxygen-level-dependent response reveals that in the left hemisphere, inverted BM activates anterior networks likely engaged in decision making and cognitive control, whereas readily recognizable upright BM activates posterior areas solely...
July 10, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28968396/bistability-non-ergodicity-and-inhibition-in-pairwise-maximum-entropy-models
#10
Vahid Rostami, PierGianLuca Porta Mana, Sonja Grün, Moritz Helias
Pairwise maximum-entropy models have been used in neuroscience to predict the activity of neuronal populations, given only the time-averaged correlations of the neuron activities. This paper provides evidence that the pairwise model, applied to experimental recordings, would produce a bimodal distribution for the population-averaged activity, and for some population sizes the second mode would peak at high activities, that experimentally would be equivalent to 90% of the neuron population active within time-windows of few milliseconds...
October 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28966573/a-chronically-implantable-bidirectional-neural-interface-for-non-human-primates
#11
Misako Komatsu, Eriko Sugano, Hiroshi Tomita, Naotaka Fujii
Optogenetics has potential applications in the study of epilepsy and neuroprostheses, and for studies on neural circuit dynamics. However, to achieve translation to clinical usage, optogenetic interfaces that are capable of chronic stimulation and monitoring with minimal brain trauma are required. We aimed to develop a chronically implantable device for photostimulation of the brain of non-human primates. We used a micro-light-emitting diode (LED) array with a flexible polyimide film. The array was combined with a whole-cortex electrocorticographic (ECoG) electrode array for simultaneous photostimulation and recording...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28959191/distinct-temporal-coordination-of-spontaneous-population-activity-between-basal-forebrain-and-auditory-cortex
#12
Josue G Yague, Tomomi Tsunematsu, Shuzo Sakata
The basal forebrain (BF) has long been implicated in attention, learning and memory, and recent studies have established a causal relationship between artificial BF activation and arousal. However, neural ensemble dynamics in the BF still remains unclear. Here, recording neural population activity in the BF and comparing it with simultaneously recorded cortical population under both anesthetized and unanesthetized conditions, we investigate the difference in the structure of spontaneous population activity between the BF and the auditory cortex (AC) in mice...
2017: Frontiers in Neural Circuits
https://www.readbyqxmd.com/read/28942061/the-behavioral-and-cognitive-relevance-of-time-varying-dynamic-changes-in-functional-connectivity
#13
REVIEW
Jessica R Cohen
Recent advances in neuroimaging methods and analysis have led to an expanding body of research that investigates how large-scale brain network organization dynamically adapts to changes in one's environment, including both internal state changes and external stimulation. It is now possible to detect changes in functional connectivity that occur on the order of seconds, both during an unconstrained resting state and during the performance of constrained cognitive tasks. It is thought that these dynamic, time-varying changes in functional connectivity, often referred to as dynamic functional connectivity (dFC), include features that are relevant to behavior and cognition...
September 20, 2017: NeuroImage
https://www.readbyqxmd.com/read/28939929/stimulus-induced-transitions-between-spike-wave-discharges-and-spindles-with-the-modulation-of-thalamic-reticular-nucleus
#14
Denggui Fan, Qingyun Wang, Jianzhong Su, Hongguang Xi
It is believed that thalamic reticular nucleus (TRN) controls spindles and spike-wave discharges (SWD) in seizure or sleeping processes. The dynamical mechanisms of spatiotemporal evolutions between these two types of activity, however, are not well understood. In light of this, we first use a single-compartment thalamocortical neural field model to investigate the effects of TRN on occurrence of SWD and its transition. Results show that the increasing inhibition from TRN to specific relay nuclei (SRN) can lead to the transition of system from SWD to slow-wave oscillation...
September 22, 2017: Journal of Computational Neuroscience
https://www.readbyqxmd.com/read/28937644/american-sign-language-alphabet-recognition-using-a-neuromorphic-sensor-and-an-artificial-neural-network
#15
Miguel Rivera-Acosta, Susana Ortega-Cisneros, Jorge Rivera, Federico Sandoval-Ibarra
This paper reports the design and analysis of an American Sign Language (ASL) alphabet translation system implemented in hardware using a Field-Programmable Gate Array. The system process consists of three stages, the first being the communication with the neuromorphic camera (also called Dynamic Vision Sensor, DVS) sensor using the Universal Serial Bus protocol. The feature extraction of the events generated by the DVS is the second part of the process, consisting of a presentation of the digital image processing algorithms developed in software, which aim to reduce redundant information and prepare the data for the third stage...
September 22, 2017: Sensors
https://www.readbyqxmd.com/read/28926184/experience-dependent-neural-plasticity-learning-and-memory-in-the-era-of%C3%A2-epitranscriptomics
#16
REVIEW
Laura J Leighton, Ke Ke, Esmi L Zajaczkowski, Jordan Edmunds, Robert C Spitale, Timothy W Bredy
In this short review, we highlight recent findings in the emerging field of epitranscriptomic mechanisms and discuss their potential role in neural plasticity, learning and memory. These include the influence of RNA modifications on activity-induced RNA structure states, RNA editing and RNA localization, and how qualitative state changes in RNA increase the functional diversity and information-carrying capacity of RNA molecules. We predict that RNA modifications may be just as important for synaptic plasticity and memory as quantitative changes in transcript and protein abundance, but with the added advantage of not being required to signal back to the nucleus, and therefore better suited to be coordinated with the temporal dynamics of learning...
September 19, 2017: Genes, Brain, and Behavior
https://www.readbyqxmd.com/read/28919850/the-detection-of-phase-amplitude-coupling-during-sensory-processing
#17
Robert A Seymour, Gina Rippon, Klaus Kessler
There is increasing interest in understanding how the phase and amplitude of distinct neural oscillations might interact to support dynamic communication within the brain. In particular, previous work has demonstrated a coupling between the phase of low frequency oscillations and the amplitude (or power) of high frequency oscillations during certain tasks, termed phase amplitude coupling (PAC). For instance, during visual processing in humans, PAC has been reliably observed between ongoing alpha (8-13 Hz) and gamma-band (>40 Hz) activity...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28918300/dynamical-properties-of-lfps-from-mice-with-unilateral-injection-of-tent
#18
Eleonora Vannini, Matteo Caleo, Santi Chillemi, Angelo Di Garbo
Local field potential (LFP) recordings were performed from the visual cortex (V1) of a focal epilepsy mouse model. Epilepsy was induced by a unilateral injection of the synaptic blocker tetanus neurotoxin (TeNT). LFP signals were simultaneously recorded from V1 of both hemispheres of each animal under acute and chronic conditions (i.e. during and after the period of TeNT action). All data were analysed by using nonlinear time series methods. Suitable values of the lag time and embedding dimension for phase space reconstruction were estimated by employing well-known methods...
September 13, 2017: Bio Systems
https://www.readbyqxmd.com/read/28913778/neural-basis-of-early-somatosensory-change-detection-a-magnetoencephalography-study
#19
G Naeije, T Vaulet, V Wens, B Marty, S Goldman, X De Tiège
The mismatch negativity (MMN) reflects the early detection of changes in sensory stimuli at the cortical level. The mechanisms underlying its genesis remain debated. This magnetoencephalography study investigates the spatio-temporal dynamics and the neural mechanisms of the magnetic somatosensory MMN. Somatosensory evoked magnetic fields elicited by tactile stimulation of the right fingertip (Single), tactile stimulation of the right middle phalanx and fingertip (Double) or omissions (Omitted) of tactile stimuli were studied in different paradigms: in oddballs where Double/Omitted followed a sequence of four Single, in sequences of two stimuli where Double occurred after one Single, and in random presentation of Double only...
September 14, 2017: Brain Topography
https://www.readbyqxmd.com/read/28912706/dynamic-neural-fields-with-intrinsic-plasticity
#20
Claudius Strub, Gregor Schöner, Florentin Wörgötter, Yulia Sandamirskaya
Dynamic neural fields (DNFs) are dynamical systems models that approximate the activity of large, homogeneous, and recurrently connected neural networks based on a mean field approach. Within dynamic field theory, the DNFs have been used as building blocks in architectures to model sensorimotor embedding of cognitive processes. Typically, the parameters of a DNF in an architecture are manually tuned in order to achieve a specific dynamic behavior (e.g., decision making, selection, or working memory) for a given input pattern...
2017: Frontiers in Computational Neuroscience
keyword
keyword
89512
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"