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https://www.readbyqxmd.com/read/28231479/intermittent-bilateral-coherence-in-physiological-and-essential-hand-tremor
#1
Soma Chakraborty, Jana Kopecká, Otakar Šprdlík, Martina Hoskovcová, Olga Ulmanová, Evžen Růžička, Martin Zapotocky
OBJECTIVE: To investigate the prevalence and the temporal structure of bilateral coherence in physiological (PT) and essential (ET) hand tremor. METHODS: Triaxial accelerometric recordings from both hands in 30 healthy subjects and 34 ET patients were analyzed using spectral coherence and wavelet coherence methods. In 12 additional healthy subjects, the relation between the hand tremor and the chest wall acceleration was evaluated using partial coherence analysis...
January 14, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/28231043/transient-oxytocin-signaling-primes-the-development-and-function-of-excitatory-hippocampal-neurons
#2
Silvia Ripamonti, Mateusz C Ambrozkiewicz, Francesca Guzzi, Marta Gravati, Gerardo Biella, Ingo Bormuth, Matthieu Hammer, Liam P Tuffy, Albrecht Sigler, Hiroshi Kawabe, Katsuhiko Nishimori, Mauro Toselli, Nils Brose, Marco Parenti, JeongSeop Rhee
Beyond its role in parturition and lactation, oxytocin influences higher brain processes that control social behavior of mammals, and perturbed oxytocin signaling has been linked to the pathogenesis of several psychiatric disorders. However, it is still largely unknown how oxytocin exactly regulates neuronal function. We show that early, transient oxytocin exposure in vitro inhibits the development of hippocampal glutamatergic neurons, leading to reduced dendrite complexity, synapse density, and excitatory transmission, while sparing GABAergic neurons...
February 23, 2017: ELife
https://www.readbyqxmd.com/read/28230841/magnetoencephalography-for-brain-electrophysiology-and-imaging
#3
REVIEW
Sylvain Baillet
We review the aspects that uniquely characterize magnetoencephalography (MEG) among the techniques available to explore and resolve brain function and dysfunction. While emphasizing its specific strengths in terms of millisecond source imaging, we also identify and discuss current practical challenges, in particular in signal extraction and interpretation. We also take issue with some perceived disadvantages of MEG, including the misconception that the technique is redundant with electroencephalography. Overall, MEG contributes uniquely to our deeper comprehension of both regional and large-scale brain dynamics: from the functions of neural oscillations and the nature of event-related brain activation, to the mechanisms of functional connectivity between regions and the emergence of modes of network communication in brain systems...
February 23, 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/28230659/sulfonylurea-blockade-of-k-atp-channels-unmasks-a-distinct-type-of-glucose-induced-ca-2-decrease-in-pancreatic-%C3%AE-cells
#4
Bo Hellman, Heléne Dansk, Eva Grapengiesser
OBJECTIVES: This study aimed to explore how sulfonylurea blockade of KATP channels affects the early Ca signals for glucose generation of insulin release. METHODS: Cytoplasmic Ca was measured with ratiometric microfluorometry in isolated mouse islets loaded with Fura-PE3. RESULTS: After sulfonylurea blockade of the KATP channels (50 μM-1 mM tolbutamide or 1 μM-1 mM gliclazide), increase of glucose from 3 to 20 mM resulted in suppression of elevated Ca during a 3- to 5-minute period...
February 23, 2017: Pancreas
https://www.readbyqxmd.com/read/28229594/2d-behaviors-of-excitons-in-cesium-lead-halide-perovskite-nanoplatelets
#5
Jing Li, Laihao Luo, Hongwen Huang, Chao Ma, Zhizhen Ye, Jie Zeng, Haiping He
Fundamental to understanding and predicting the optoelectronic properties of semiconductors is the basic parameters of excitons such as oscillator strength and exciton binding energy. However, such knowledge of CsPbBr3 perovskite, a promising optoelectronic material, is still unexplored. Here we demonstrate that quasi-two-dimensional (quasi-2D) CsPbBr3 nanoplatelets (NPLs) with 2D exciton behaviors serve as an ideal system for the determination of these parameters. It is found that the oscillator strength of CsPbBr3 NPLs is up to 1...
February 23, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28229302/tremor-analysis-separates-parkinson-s-disease-and-dopamine-receptor-blockers-induced-parkinsonism
#6
Aasef G Shaikh
Parkinson's disease, the most common cause of parkinsonism is often difficult to distinguish from its second most common etiology due to exposure to dopamine receptor blocking agents such as antiemetics and neuroleptics. Dual axis accelerometry was used to quantify tremor in 158 patients with parkinsonism; 62 had Parkinson's disease and 96 were clinically diagnosed with dopamine receptor blocking agent-induced parkinsonism. Tremor was measured while subjects rested arms (resting tremor), outstretched arms in front (postural tremor), and reached a target (kinetic tremor)...
February 22, 2017: Neurological Sciences
https://www.readbyqxmd.com/read/28228580/probing-phase-and-frequency-dependent-characteristics-of-cortical-neurons-using-combined-transcranial-alternating-current-stimulation-and-transcranial-magnetic
#7
Sara Jeanne Hussain, Nivethida Thirugnanasambandam
Paired-pulse transcranial magnetic stimulation (TMS) and peripheral stimulation combined with TMS can be used to study cortical interneuronal circuitry. By combining these procedures with concurrent transcranial alternating current stimulation (tACS), Guerra and colleagues recently showed that different cortical interneuronal populations are differentially modulated by the phase and frequency of tACS-imposed oscillations (Guerra et al. 2016, Phase dependency of the human primary motor cortex and cholinergic inhibition cancellation during beta tACS, Cerebral Cortex 26:3977-2990)...
February 22, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28228579/network-wide-oscillations-in-the-parkinsonian-state-alterations-in-neuronal-activities-occur-in-the-premotor-cortex-in-parkinsonian-non-human-primates
#8
Jing Wang, Luke A Johnson, Alicia L Jensen, Kenneth B Baker, Jerrold L Vitek
A number of studies suggest that Parkinson's disease (PD) is associated with alterations of neuronal activity patterns in the basal-ganglia-thalamocortical circuit. There are limited electrophysiological data, however, describing how premotor cortex, which is involved in movement and decision making, is likely impacted in PD. In this study, spontaneous local field potential (LFP) and single unit neuronal activity were recorded in the dorsal premotor area of non-human primates in both the naïve and parkinsonian state using the MPTP model of parkinsonism...
February 22, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28227964/cross-entropy-optimization-for-neuromodulation
#9
Harleen K Brar, Yunpeng Pan, Babak Mahmoudi, Evangelos A Theodorou, Harleen K Brar, Yunpeng Pan, Babak Mahmoudi, Evangelos A Theodorou, Yunpeng Pan, Harleen K Brar, Babak Mahmoudi, Evangelos A Theodorou
This study presents a reinforcement learning approach for the optimization of the proportional-integral gains of the feedback controller represented in a computational model of epilepsy. The chaotic oscillator model provides a feedback control systems view of the dynamics of an epileptic brain with an internal feedback controller representative of the natural seizure suppression mechanism within the brain circuitry. Normal and pathological brain activity is simulated in this model by adjusting the feedback gain values of the internal controller...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227759/mining-cross-frequency-coupling-microstates-cfc%C3%AE-states-from-eeg-recordings-during-resting-state-and-mental-arithmetic-tasks
#10
Stavros I Dimitriadis, Yu Sun, Nitish Thakor, Anastasios Bezerianos, Stavros I Dimitriadis, Yu Sun, Nitish Thakor, Anastasios Bezerianos, Stavros I Dimitriadis, Yu Sun, Nitish Thakor, Anastasios Bezerianos
The functional brain connectivity has been studied by analyzing synchronization between dynamic oscillations of identical frequency or between different frequencies of distinct brain areas. It has been hypothesized that cross-frequency coupling (CFC) between different frequency bands is the carrier mechanism for the coordination of global and local neural processes and hence supports the distributed information processing in the brain. In the present study, we attempt to study the dynamic evolution of CFC at resting-state and during a mental task...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227755/differentiation-of-spindle-associated-hippocampal-hfos-based-on-a-correlation-analysis
#11
Daniel Lachner Piza, Jonas C Bruder, Julia Jacobs, Andreas Schulze-Bonhage, Thomas Stieglitz, Matthias Dumpelmann, Daniel Lachner Piza, Jonas C Bruder, Julia Jacobs, Andreas Schulze-Bonhage, Thomas Stieglitz, Matthias Dumpelmann, Thomas Stieglitz, Matthias Dumpelmann, Jonas C Bruder, Andreas Schulze-Bonhage, Daniel Lachner Piza, Julia Jacobs
High Frequency Oscillations (HFOs) have been described as biomarkers of epileptogenic tissue; however their pathological/physiological classification poses a challenge to their predictive power. For the population of ripples co-occurring with sleep spindles, those ripples improving the antiparallel correlation of ripple-peaks and sleep spindle-troughs were classified as coupled-ripples and the rest as uncoupled-ripples. For the same population of ripples two reference groups called in-SOZ and non-SOZ were formed according to the ripples' location inside or outside the seizure onset zone (SOZ)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227754/brain-heart-linear-and-nonlinear-dynamics-during-visual-emotional-elicitation-in-healthy-subjects
#12
G Valenza, A Greco, C Gentili, A Lanata, N Toschi, R Barbieri, L Sebastiani, D Menicucci, A Gemignani, E P Scilingo, G Valenza, A Greco, C Gentili, A Lanata, N Toschi, R Barbieri, L Sebastiani, D Menicucci, A Gemignani, E P Scilingo, A Lanata, A Gemignani, E P Scilingo, A Greco, D Menicucci, L Sebastiani, C Gentili, N Toschi, R Barbieri, G Valenza
This study investigates brain-heart dynamics during visual emotional elicitation in healthy subjects through linear and nonlinear coupling measures of EEG spectrogram and instantaneous heart rate estimates. To this extent, affective pictures including different combinations of arousal and valence levels, gathered from the International Affective Picture System, were administered to twenty-two healthy subjects. Time-varying maps of cortical activation were obtained through EEG spectral analysis, whereas the associated instantaneous heartbeat dynamics was estimated using inhomogeneous point-process linear models...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227749/reconstructing-multivariate-causal-structure-between-functional-brain-networks-through-a-laguerre-volterra-based-granger-causality-approach
#13
Andrea Duggento, Gaetano Valenza, Luca Passamonti, Maria Guerrisi, Riccardo Barbieri, Nicola Toschi, Andrea Duggento, Gaetano Valenza, Luca Passamonti, Maria Guerrisi, Riccardo Barbieri, Nicola Toschi, Andrea Duggento, Nicola Toschi, Maria Guerrisi, Luca Passamonti, Riccardo Barbieri, Gaetano Valenza
Classical multivariate approaches based on Granger causality (GC) which estimate functional connectivity in the brain are almost exclusively based on autoregressive models. Nevertheless, information available from past samples is limited due to both signal autocorrelation and necessarily low model orders. Consequently, multiple time-scales interactions are usually unaccounted for. To overcome these limitations, in this study we propose the use of discrete-time orthogonal Laguerre basis functions within a Wiener-Volterra decomposition of the BOLD signals to perform effective GC assessments of brain functional connectivity...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227698/predicting-brain-stimulation-treatment-outcomes-of-depressed-patients-through-the-classification-of-eeg-oscillations
#14
Alaa M Al-Kaysi, Ahmed Al-Ani, Colleen K Loo, Michael Breakspear, Tjeerd W Boonstra, Alaa M Al-Kaysi, Ahmed Al-Ani, Colleen K Loo, Michael Breakspear, Tjeerd W Boonstra, Michael Breakspear, Ahmed Al-Ani, Tjeerd W Boonstra, Colleen K Loo
Major depressive disorder (MDD) is a mental disorder that is characterized by negative thoughts, mood and behavior. Transcranial direct current stimulation (tDCS) has recently emerged as a promising brain-stimulation treatment for MDD. A standard tDCS treatment involves numerous sessions that run over a few weeks, however, not all participants respond to this type of treatment. This study aims to predict which patients improve in mood and cognition in response to tDCS treatment by analyzing electroencephalography (EEG) of MDD patients that was collected at the start of tDCS treatment...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227622/energy-harvesting-from-human-walking-to-power-biomedical-devices-using-oscillating-generation
#15
Jose A Montoya, Dulce M Mariscal, Edwar Romero, Jose A Montoya, Dulce M Mariscal, Edwar Romero, Dulce M Mariscal, Jose A Montoya, Edwar Romero
This work summarizes the energy generation limits from walking employing a pendulum-based generation system. Self-winding wristwatches have exploited successfully this energy input technique for decades. Pendulum-based planar devices use the rotation to produce energy for inertial generators. Then the oscillations of body motion during locomotion present an opportunity to extract kinetic energy from planar generators. The sinusoidal motion of the center of gravity of the body, on the sagittal and frontal planes, and the limbs swinging are compliant with oscillating devices...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227592/saw-lc-coupled-resonator-wideband-vco-for-medical-telemetry
#16
Madhav Venkateswaran, Mark Hillig, James E Brown, Paul J Stadnik, Jeffrey A Von Arx, Brian Sutton, Larry J Stotts, Madhav Venkateswaran, Mark Hillig, James E Brown, Paul J Stadnik, Jeffrey A Von Arx, Brian Sutton, Larry J Stotts, Mark Hillig, Jeffrey A Von Arx, Madhav Venkateswaran, Brian Sutton, James E Brown, Paul J Stadnik, Larry J Stotts
Wireless links with implantable devices can help in real-time monitoring of symptoms, irregularities, implanted device efficacy and their reconfiguration. We present the design of a low-power wideband voltage controlled oscillator (VCO) to facilitate implantable wireless telemetry. A coupled SAW-LC resonator design combines high Q and spectral purity of a SAW element and tunability of an LC-tank. The designed 2.7 MHz bandwidth VCO is suitable for full duplex communication protocols in the MedRadio band with frequency agility and higher duty cycles, in conformance with FCC regulations...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227526/valence-dependent-changes-in-visual-arousing-elicitation-an-exploratory-study-in-eeg-gamma-oscillations
#17
Alberto Greco, Gaetano Valenza, Enzo Pasquale Scilingo, Alberto Greco, Gaetano Valenza, Enzo Pasquale Scilingo, Gaetano Valenza, Enzo Pasquale Scilingo, Alberto Greco
Emotion regulation involves several brain areas such as prefrontal cortex, amygdala, and insular cortex. However, considering different levels of arousing elicitations, how such a brain dynamics is affected by emotional pleasant/unpleasant (valence) elicitation is not fully understood. To this aim, we propose an Electroencephalographic (EEG)-based preliminary study in which 22 healthy subjects were elicited through affective pictures gathered from the International Affective Picture System. Considering 4 arousing levels, each of which including two valence levels (pleasant and unpleasant), we investigated EEG power spectra and functional connectivity...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227504/classification-of-pilot-induced-oscillations-during-in-flight-piloting-exercises-using-dry-eeg-sensor-recordings
#18
Clara A Scholl, Yu Mike Chi, Michael Elconin, William R Gray, Mark A Chevillet, Eric A Pohlmeyer, Clara A Scholl, Yu Mike Chi, Michael Elconin, William R Gray, Mark A Chevillet, Eric A Pohlmeyer, Yu Mike Chi, Mark A Chevillet, William R Gray, Eric A Pohlmeyer, Michael Elconin, Clara A Scholl
Pilot-Induced Oscillations (PIOs) are potentially hazardous piloting phenomena in which a pilot's control-inputs and the aircraft control-responses have (for any of a number of possible reasons) become out of phase. During PIOs, aggressive over-controlling on the part of the pilot in order to overcome a perceived lack of control can lead to complete loss of aircraft control. This study shows data recorded from a Cognionics dry electrode system during actual flight exercises can be used on a second-to-second basis to classify whether a pilot was undergoing a PIO event or if a PIO was imminent...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227365/integrated-quantification-based-on-confocal-imaging-cell-crowding-modulates-heterogeneity-in-gpcr-mediated-calcium-oscillation
#19
Jophin G Joseph, S Nanda, S Vennamalla, G Bhure, Ranjana Singh, Soumya Jana, Lopamudra Giri, Jophin G Joseph, S Nanda, S Vennamalla, G Bhure, Ranjana Singh, Soumya Jana, Lopamudra Giri, Soumya Jana, Lopamudra Giri, Jophin G Joseph, S Nanda, Ranjana Singh, G Bhure, S Vennamalla
Results from single cell imaging, facilitated by high resolution microscopy, have demonstrated cell-to-cell variability within the same cell population in contexts ranging from cell growth to cell migration. Recent studies suggest that such variability conveys important information about diseased states. However, manual analysis and interpretation of heterogeneous calcium oscillation based on time-lapsed images, as practiced today, is tedious, and essentially infeasible for large datasets. As a practical alternative, we present an integrated platform that includes calcium imaging using confocal microscope, algorithmic cell segmentation, and statistical analysis...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227346/respiratory-rate-estimation-from-multilead-directions-based-on-ecg-delineation
#20
M Noriega, E J Maranon, D Romero, M Orini, R Almeida, M Noriega, E J Maranon, D Romero, M Orini, R Almeida, M Orini, M Noriega, R Almeida, D Romero, E J Maranon
Estimating the instantaneous respiratory rate (Rr) from the electrocardiogram (ECG) is of interest as respiration direct measurement in clinical situations is often cumbersome. In this study, the Rr was estimated from the same Final Directions of maximum projection (FD) used for multi lead ECG automatic delineation. Power spectral analysis over the directions based on QRS complex main peak and T wave onset, peak and end spatial loops was used for Rr estimation. On a subset of the Physionet MGH/MF dataset, the proposed method yielded more accurate Rr estimates (minimum mean absolute error (MAE), 2...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
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