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Eeg phase amplitude coupling

Soheila Samiee, Maxime Lévesque, Massimo Avoli, Sylvain Baillet
Polyrhythmic coupling of oscillatory components in electrophysiological signals results from the interactions between neuronal sub-populations within and between cell assemblies. Since the mechanisms underlying epileptic disorders should affect such interactions, abnormal level of cross-frequency coupling is expected to provide a signal marker of epileptogenesis. We measured phase-amplitude coupling (PAC), a form of cross-frequency coupling between neural oscillations, in a rodent model of mesial temporal lobe epilepsy...
February 24, 2018: Neurobiology of Disease
Christopher K Kovach, Hiroyuki Oya, Hiroto Kawasaki
Most biological signals are non-Gaussian, reflecting their origins in highly nonlinear physiological systems. A versatile set of techniques for studying non-Gaussian signals relies on the spectral representations of higher moments, known as polyspectra, which describe forms of cross-frequency dependence that do not arise in time-invariant Gaussian signals. The most commonly used of these employ the bispectrum. Recently, other measures of cross-frequency dependence have drawn interest in EEG literature, in particular those which address phase-amplitude coupling (PAC)...
February 23, 2018: NeuroImage
J Matias Palva, Sheng H Wang, Satu Palva, Alexander Zhigalov, Simo Monto, Matthew J Brookes, Jan-Mathijs Schoffelen, Karim Jerbi
When combined with source modeling, magneto- (MEG) and electroencephalography (EEG) can be used to study long-range interactions among cortical processes non-invasively. Estimation of such inter-areal connectivity is nevertheless hindered by instantaneous field spread and volume conduction, which artificially introduce linear correlations and impair source separability in cortical current estimates. To overcome the inflating effects of linear source mixing inherent to standard interaction measures, alternative phase- and amplitude-correlation based connectivity measures, such as imaginary coherence and orthogonalized amplitude correlation have been proposed...
February 22, 2018: NeuroImage
Forooz Shahbazi Avarvand, Sarah Bartz, Christina Andreou, Wojciech Samek, Gregor Leicht, Christoph Mulert, Andreas K Engel, Guido Nolte
We propose a new method for the localization of nonlinear cross-frequency coupling in EEG and MEG data analysis, based on the estimation of bicoherences at the source level. While for the analysis of rhythmic brain activity, source directions are commonly chosen to maximize power, we suggest to maximize bicoherence instead. The resulting nonlinear cost function can be minimized effectively using a gradient approach. We argue, that bicoherence is also a generally useful tool to analyze phase-amplitude coupling (PAC), by deriving formal relations between PAC and bispectra...
February 5, 2018: NeuroImage
Milan Halgren, Daniel Fabó, István Ulbert, Joseph R Madsen, Lorand Erőss, Werner K Doyle, Orrin Devinsky, Donald Schomer, Sydney S Cash, Eric Halgren
The neocortex is composed of six anatomically and physiologically specialized layers. It has been proposed that integration of activity across cortical areas is mediated anatomically by associative connections terminating in superficial layers, and physiologically by slow cortical rhythms. However, the means through which neocortical anatomy and physiology interact to coordinate neural activity remains obscure. Using laminar microelectrode arrays in 19 human participants, we found that most EEG activity is below 10-Hz (delta/theta) and generated by superficial cortical layers during both wakefulness and sleep...
February 1, 2018: Scientific Reports
Austin E Soplata, Michelle M McCarthy, Jason Sherfey, Shane Lee, Patrick L Purdon, Emery N Brown, Nancy Kopell
The anesthetic propofol elicits many different spectral properties on the EEG, including alpha oscillations (8-12 Hz), Slow Wave Oscillations (SWO, 0.1-1.5 Hz), and dose-dependent phase-amplitude coupling (PAC) between alpha and SWO. Propofol is known to increase GABAA inhibition and decrease H-current strength, but how it generates these rhythms and their interactions is still unknown. To investigate both generation of the alpha rhythm and its PAC to SWO, we simulate a Hodgkin-Huxley network model of a hyperpolarized thalamus and corticothalamic inputs...
December 2017: PLoS Computational Biology
A L Gaskell, D F Hight, J Winders, G Tran, A Defresne, V Bonhomme, A Raz, J W Sleigh, R D Sanders
Background: The isolated forearm test (IFT) is the gold standard test of connected consciousness (awareness of the environment) during anaesthesia. The frontal alpha-delta EEG pattern (seen in slow wave sleep) is widely held to indicate anaesthetic-induced unconsciousness. A priori we proposed that one responder with the frontal alpha-delta EEG pattern would falsify this concept. Methods: Frontal EEG was recorded in a subset of patients from three centres participating in an international multicentre study of IFT responsiveness following tracheal intubation...
October 1, 2017: British Journal of Anaesthesia
Min-Hee Ahn, Sung Kwang Hong, Byoung-Kyong Min
Tinnitus is a psychoacoustic phantom perception of currently unknown neuropathology. Despite a growing number of post-stimulus tinnitus studies, uncertainty still exists regarding the neural signature of tinnitus in the resting-state brain. In the present study, we used high-gamma cross-frequency coupling and a Granger causality analysis to evaluate resting-state electroencephalographic (EEG) data in healthy participants and patients with tinnitus. Patients with tinnitus lacked robust frontal delta-phase/central high-gamma-amplitude coupling that was otherwise clearly observed in healthy participants...
December 2017: Hearing Research
A Ahnaou, D Moechars, L Raeymaekers, R Biermans, N V Manyakov, A Bottelbergs, C Wintmolders, K Van Kolen, T Van De Casteele, J A Kemp, W H Drinkenburg
Synaptic dysfunction and disconnectivity are core deficits in Alzheimer's disease (AD), preceding clear changes in histopathology and cognitive functioning. Here, the early and late effects of tau pathology induction on functional network connectivity were investigated in P301L mice. Multichannel EEG oscillations were used to compute (1) coherent activity between the prefrontal cortex (PFC) and hippocampus (HPC) CA1-CA3 networks; (2) phase-amplitude cross frequency coupling (PAC) between theta and gamma oscillations, which is instrumental in adequate cognitive functioning; (3) information processing as assessed by auditory evoked potentials and oscillations in the passive oddball mismatch negativity-like (MMN) paradigm...
October 27, 2017: Scientific Reports
Stavros I Dimitriadis, Ioannis Tarnanas, Mark Wiederhold, Brenda Wiederhold, Magda Tsolaki, Elgar Fleisch
INTRODUCTION: We sought to identify whether intensive 10-week mobile health mnemonic strategy training (MST) could shift the resting-state brain network more toward cortical-level integration, which has recently been proven to reflect the reorganization of the brain networks compensating the cognitive decline. METHODS: One hundred fifty-eight patients with mild cognitive impairment (MCI) were selected and participated in 10-week training lasting 90 min/d of memory training...
November 2016: Alzheimer's & Dementia: Translational Research & Clinical Interventions
Jesus Poza, Alejandro Bachiller, Carlos Gomez, Maria Garcia, Pablo Nunez, Javier Gomez-Pilar, Miguel A Tola-Arribas, Monica Cano, Roberto Hornero
This study was aimed at exploring phase-amplitude coupling (PAC) patterns of neural activity in dementia due to Alzheimer's disease (AD). For this task, five minutes of spontaneous electroencephalographic (EEG) activity from 22 patients with mild AD and 16 cognitively healthy controls were studied. To assess PAC patterns, phase-locking value was computed between the phase of low frequencies and the power of high frequencies within each sensor. Our results showed that high-frequency gamma power is phase-locked to the alpha peak in EEG signals...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Reza Sameni, Esmaeil Seraj
OBJECTIVE: The instantaneous phase (IP) and instantaneous frequency (IF) of the electroencephalogram (EEG) are considered as notable complements for the EEG spectrum. The calculation of these parameters commonly includes narrow-band filtering, followed by the calculation of the signal's analytical form. The calculation of the IP and IF is highly susceptible to the filter parameters and background noise level, especially in low analytical signal amplitudes. The objective of this study is to propose a robust statistical framework for EEG IP/IF estimation and analysis...
November 30, 2017: Physiological Measurement
Atul Maheshwari, Abraham Akbar, Mai Wang, Rachel L Marks, Katherine Yu, Suhyeorn Park, Brett L Foster, Jeffrey L Noebels
KEY POINTS: In two monogenic models of absence epilepsy, interictal beta/gamma power is augmented in homozygous stargazer (stg/stg) but not homozygous tottering (tg/tg) mice. There are distinct gene-linked patterns of aberrant phase-amplitude coupling in the interictal EEG of both stg/stg and tg/tg mice, compared to +/+ and stg/+ mice. Treatment with ethosuximide significantly blocks seizures in both genotypes, but the abnormal phase-amplitude coupling remains. Seizure-free stg/+ mice have normal power and phase-amplitude coupling, but beta/gamma power is significantly reduced with NMDA receptor blockade, revealing a latent cortical network phenotype that is separable from, and therefore not a result of, seizures...
December 1, 2017: Journal of Physiology
N Mrachacz-Kersting, M Voigt, Ajt Stevenson, S Aliakbaryhosseinabadi, N Jiang, K Dremstrup, D Farina
A peripherally generated afferent volley that arrives at the peak negative (PN) phase during the movement related cortical potential (MRCP) induces significant plasticity at the cortical level in healthy individuals and chronic stroke patients. Transferring this type of associative brain-computer interface (BCI) intervention into the clinical setting requires that the proprioceptive input is comparable to the techniques implemented during the rehabilitation process. These consist mainly of functional electrical stimulation (FES) and passive movement induced by an actuated orthosis...
August 28, 2017: Brain Research
Amir Omidvarnia, Mangor Pedersen, David N Vaughan, Jennifer M Walz, David F Abbott, Andrew Zalesky, Graeme D Jackson
Simultaneous scalp EEG-fMRI recording is a noninvasive neuroimaging technique for combining electrophysiological and hemodynamic aspects of brain function. Despite the time-varying nature of both measurements, their relationship is usually considered as time-invariant. The aim of this study was to detect direct associations between scalp-recorded EEG and regional changes of hemodynamic brain connectivity in focal epilepsy through a time-frequency paradigm. To do so, we developed a voxel-wise framework that analyses wavelet coherence between dynamic regional phase synchrony (DRePS, calculated from fMRI) and band amplitude fluctuation (BAF) of a target EEG electrode with dominant interictal epileptiform discharges (IEDs)...
November 2017: Human Brain Mapping
K J Mullinger, M T Cherukara, R B Buxton, S T Francis, S D Mayhew
Post-stimulus undershoots, negative responses following cessation of stimulation, are widely observed in functional magnetic resonance (fMRI) blood oxygenation level dependent (BOLD) data. However, the debate surrounding whether the origin of this response phase is neuronal or vascular, and whether it provides functionally relevant information, that is additional to what is contained in the primary response, means that undershoots are widely overlooked. We simultaneously recorded electroencephalography (EEG), BOLD and cerebral blood-flow (CBF) [obtained from arterial spin labelled (ASL) fMRI] fMRI responses to hemifield checkerboard stimulation to test the potential neural origin of the fMRI post-stimulus undershoot...
August 15, 2017: NeuroImage
Lauren E Ethridge, Stormi P White, Matthew W Mosconi, Jun Wang, Ernest V Pedapati, Craig A Erickson, Matthew J Byerly, John A Sweeney
BACKGROUND: Studies in the fmr1 KO mouse demonstrate hyper-excitability and increased high-frequency neuronal activity in sensory cortex. These abnormalities may contribute to prominent and distressing sensory hypersensitivities in patients with fragile X syndrome (FXS). The current study investigated functional properties of auditory cortex using a sensory entrainment task in FXS. METHODS: EEG recordings were obtained from 17 adolescents and adults with FXS and 17 age- and sex-matched healthy controls...
2017: Molecular Autism
Wenjuan Jian, Minyou Chen, Dennis J McFarland
Phase-locking value (PLV) is a potentially useful feature in sensorimotor rhythm-based brain-computer interface (BCI). However, volume conduction may cause spurious zero-phase coupling between two EEG signals and it is not clear whether PLV effects are independent of spectral amplitude. Volume conduction might be reduced by spatial filtering, but it is uncertain what impact this might have on PLV. Therefore, the goal of this study was to explore whether zero-phase PLV is meaningful and how it is affected by spatial filtering...
November 2017: Medical & Biological Engineering & Computing
Jun Wang, Lauren E Ethridge, Matthew W Mosconi, Stormi P White, Devin K Binder, Ernest V Pedapati, Craig A Erickson, Matthew J Byerly, John A Sweeney
BACKGROUND: Cortical hyperexcitability due to abnormal fast-spiking inhibitory interneuron function has been documented in fmr1 KO mice, a mouse model of the fragile X syndrome which is the most common single gene cause of autism and intellectual disability. METHODS: We collected resting state dense-array electroencephalography data from 21 fragile X syndrome (FXS) patients and 21 age-matched healthy participants. RESULTS: FXS patients exhibited greater gamma frequency band power, which was correlated with social and sensory processing difficulties...
2017: Journal of Neurodevelopmental Disorders
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
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