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Moving magnetoencephalography towards real-world applications with a wearable system

Elena Boto, Niall Holmes, James Leggett, Gillian Roberts, Vishal Shah, Sofie S. Meyer, Leonardo Duque Muñoz, Karen J. Mullinger, Tim M. Tierney, Sven Bestmann, Gareth R. Barnes, Richard Bowtell (+1 others)
2018 Nature  
For completeness we also measured the size of the artifact relative to the beta rebound (the only phase of the beta response still visible in the EEG data).  ...  For example, one could use independent component analysis applied at the sensor level 23 (though this potentially poses problems if muscle artifact is task-correlated).  ... 
doi:10.1038/nature26147 pmid:29562238 fatcat:hbrn4xargvcztapszehroekhfa

How to Build a Functional Connectomic Biomarker for Mild Cognitive Impairment From Source Reconstructed MEG Resting-State Activity: The Combination of ROI Representation and Connectivity Estimator Matters

Stavros I. Dimitriadis, María E. López, Ricardo Bruña, Pablo Cuesta, Alberto Marcos, Fernando Maestú, Ernesto Pereda
2018 Frontiers in Neuroscience  
Our analysis supports the notion of analyzing FCG simultaneously in intra and cross-frequency whole brain interactions with various connectivity estimators in beamformed recordings.  ...  Classification performance based on the multi-layer participation coefficient, a multiplexity index reached 52% for iPLV and 52% for CorrEnv.  ...  Artifact-related components were eliminated, and segments containing persistent oculographic artifacts were removed. Last, data was segmented in 4-s epochs of artifact-free data.  ... 
doi:10.3389/fnins.2018.00306 pmid:29910704 pmcid:PMC5992286 fatcat:zvktrsy7sra4pbpgz6ats5lnjy

Tracking the Effects of Top–Down Attention on Word Discrimination Using Frequency-tagged Neuromagnetic Responses

Maxime Niesen, Marc Vander Ghinst, Mathieu Bourguignon, Vincent Wens, Julie Bertels, Serge Goldman, Georges Choufani, Sergio Hassid, Xavier De Tiege
2020 Journal of Cognitive Neuroscience  
This area therefore appears to play a crucial role in selective verbal attentional processes for this early step of speech processing  ...  Steady-state neuromagnetic responses were identified with spectral analysis at sensor and source levels. Significant sensor responses peaked at 0.54 and 2.17 Hz in both conditions.  ...  Mathieu Bourguignon was supported by the Marie Skłodowska-Curie Action of the European Commission (Grant 743562) and by the Spanish Ministry of Economy and Competitiveness (grant PSI2016-77175-P).  ... 
doi:10.1162/jocn_a_01522 pmid:31933439 fatcat:w3wihrymafckpi6bnzypiiwnbq

Novel Noise Reduction Methods [chapter]

Samu Taulu, Juha Simola, Jukka Nenonen, Lauri Parkkonen
2014 Magnetoencephalography  
In this chapter, we review the basic characteristics of MEG signals, give a short review on traditional approaches to suppress noise, and describe some examples of modern noise reduction methods.  ...  Therefore, to enable reliable data analysis, it is very important to reduce the contribution of noise in MEG signals as efficiently as possible.  ...  Consequently, the amplitude of the neuromagnetic signal detected in MEG is in the range from 10 to 1,000 fT.  ... 
doi:10.1007/978-3-642-33045-2_2 fatcat:erbdkhy2svfsfgtrau5endmnvq

A Tactile Virtual Reality for the Study of Active Somatosensation

Arindam Bhattacharjee, Diljit Singh Kajal, Alessandra Patrono, Yiwen Li Hegner, Massimiliano Zampini, Cornelius Schwarz, Christoph Braun
2020 Frontiers in Integrative Neuroscience  
In further studies, the noise introduced by the stimulator in neuromagnetic recordings was quantified and somatosensory evoked fields for active and passive touch were recorded.  ...  Due to the compatibility of the stimulator with neuroimaging techniques such as MEG, and based on the feasibility to record somatosensory-related neuromagnetic brain activity the apparatus has immense  ...  Amplitudes of the M60 component were larger in the active touch condition than in the passive condition (Figure 7).  ... 
doi:10.3389/fnint.2020.00005 pmid:32132905 pmcid:PMC7040627 fatcat:6fge5i6k5bhfli56f4voql3f6m

Task-related power and coherence changes in neuromagnetic activity during visuomotor coordination

Yanqing Chen, Mingzhou Ding, Scott Kelso
2003 Experimental Brain Research  
Neuromagnetic activities in the alpha (8-14 Hz), beta (15-30 Hz) and gamma (30-50 Hz) ranges were shown to correlate with different aspects of the task.  ...  of power in the alpha range (8-14 Hz) in sensorimotor channels of both hemispheres, and an increase of coherence among a subset of these channels.  ...  Acknowledgements Preliminary results from this paper were presented by Y.C. at the 29th Society for Neuroscience Annual Meeting in Miami, FL (1999) and by S.K. at the 12th International Conference on Biomagnetism  ... 
doi:10.1007/s00221-002-1244-0 pmid:12478401 fatcat:6i6c54pntbckbgr6xumk2lpk64

Cross-frequency dynamics of neuromagnetic oscillatory activity: Two mechanisms of emotion regulation

Tzvetan Popov, Astrid Steffen, Nathan Weisz, Gregory A. Miller, Brigitte Rockstroh
2012 Psychophysiology  
Local coupling of alpha phase to gamma amplitude within a medial prefrontal region and long-range synchrony of medial prefrontal, occipital, and temporoparietal regions index mechanisms of prefrontal top-down  ...  MEG was measured in 24 subjects during passive viewing of neutral and unpleasant pictures and emotion regulation by cognitive reappraisal.  ...  We thank Simon Hanslmayr for comments on the manuscript, Tobias Staudigl for support regarding the cross-frequency coupling analysis, and Christian Pietrek, Johanna Fiess, and Ursel Lommen for assistance  ... 
doi:10.1111/j.1469-8986.2012.01484.x pmid:23074972 fatcat:dretyeclyrctjnjqfnofyucoky

Independent Components of Magnetoencephalography: Localization

Akaysha C. Tang, Barak A. Pearlmutter, Natalie A. Malaszenko, Dan B. Phung, Bethany C. Reeb
2002 Neural Computation  
Independent component analysis (ICA) is a class of decomposition methods that separate sources from mixtures of signals.  ...  In this chapter, we used second order blind identification (SOBI), one of the ICA method, to demonstrate its advantages in identifying magnetic signals associated with neural information processing.  ...  SOBI assumes that the components are statistically independent in time, and not necessarily orthogonal in space.  ... 
doi:10.1162/089976602760128036 pmid:12180404 fatcat:zrj2pbssvffureyzgwx6lavezy

Maturation of auditory temporal integration and inhibition assessed with event-related potentials (ERPs)

Allison M Fox, Mike Anderson, Corinne Reid, Tim Smith, Dorothy VM Bishop
2010 BMC Neuroscience  
In children, the amplitude of the P1 component was attenuated at ISIs below 200 ms, consistent with a refractory process.  ...  In adults, late N1 amplitude was larger for the second tone of the tone pair when separated by ISIs as short as 100 ms, consistent with the perceptual integration of successive stimuli within the temporal  ...  Thanks to John Love for technical support, Aoibheann O'Brien and Catherine Campbell for co-ordination of Project K.I.D.S, and to Lucy Cragg, Claire Nulsen, and Pia Van Beek for assistance with data collection  ... 
doi:10.1186/1471-2202-11-49 pmid:20398353 pmcid:PMC2868034 fatcat:g73eztch35fg3dp7hbqjswy52u

Dexterous manual movement facilitates information processing in the primary somatosensory cortex: A magnetoencephalographic study

Toshiaki Wasaka, Tetsuo Kida, Ryusuke Kakigi
2021 European Journal of Neuroscience  
The amplitude of the M20 and M30 components showed a significant reduction during both manual tasks compared to the stationary task, whereas the M38 component showed a significant enhancement in amplitude  ...  The interaction between the somatosensory and motor systems is important for control of movement in humans.  ...  This study was supported by a Grant-in-Aid for Scientific Research (C) to T.W. (18K10959) and the Cooperative Study Program of National Institute for Physiological Sciences.  ... 
doi:10.1111/ejn.15310 pmid:33987876 fatcat:h3uhohwusbgs7cq5u6zjphm3ba

Neural Representations of Complex Temporal Modulations in the Human Auditory Cortex

Nai Ding, Jonathan Z. Simon
2009 Journal of Neurophysiology  
Neural representations of complex temporal modulations in the human auditory cortex.  ...  The modulation functions E(t) and ⌽(t) determine the amplitude and phase of each Fourier component but cannot be inferred directly from any single component.  ...  The waveforms of the instantaneous amplitude and phase are roughly in phase.  ... 
doi:10.1152/jn.00523.2009 pmid:19692508 pmcid:PMC2777829 fatcat:yuq4l74fkja3dnph6t2pg4ekpy

Evidence of pitch processing in the N100m component of the auditory evoked field

Annemarie Seither-Preisler, Roy Patterson, Katrin Krumbholz, Stefan Seither, Bernd Lütkenhöner
2006 Hearing Research  
The latency of the N100m component of the auditory evoked field (AEF) is sensitive to the period and spectrum of a sound.  ...  The stimuli were harmonic tones (spectral range: 800-5000 Hz) with periods corresponding to 100, 200, 400, and 800 Hz. The frequency components were in sine, alternating or random phase.  ...  Ray Meddis and Dr. Enrique Lopez-Poveda for their support in specifying the physiological AIMmodel parameters.  ... 
doi:10.1016/j.heares.2006.01.003 pmid:16464550 fatcat:ez2veel7bba7tmukvuspcjftgm

Altered visual entrainment in patients with Alzheimer's disease: magnetoencephalography evidence

Seth D Springer, Alex I Wiesman, Pamela E May, Mikki Schantell, Hallie J Johnson, Madelyn P Willett, Camilo A Castelblanco, Jacob A Eastman, Nicholas J Christopher-Hayes, Sara L Wolfson, Craig M Johnson, Daniel L Murman (+1 others)
2022 Brain Communications  
To fill this gap, we recorded magnetoencephalography during a 15 Hz visual entrainment paradigm in amyloid-positive patients on the Alzheimer's disease spectrum and compared their neural responses to a  ...  patients whose absolute entrainment amplitude was closer to the level seen in controls had better cognitive function.  ...  Each participant completed 120 trials, which resulted in a total recording time of about 9 minutes.  ... 
doi:10.1093/braincomms/fcac198 pmid:35974799 pmcid:PMC9374481 fatcat:omtj5ykoj5b25oiorsvzaaht3q

Tactile stimulation accelerates behavioral responses to visual stimuli through enhancement of occipital gamma-band activity

Markus Bauer, Robert Oostenveld, Pascal Fries
2009 Vision Research  
be the best predictor of the faster behavioral response latencies, suggesting a key-role of oscillatory activity for cross-modal integration.  ...  Presence of a task-irrelevant tactile stimulus leads to faster behavioral responses and earlier and stronger gamma-band synchronization in occipital cortex, irrespective of the relative location of the  ...  This was done to remove stimulus-phase-locked components from the time-frequency-representation.  ... 
doi:10.1016/j.visres.2009.03.014 pmid:19324067 fatcat:bnygw32dwnam7cxrqlr56jm2pe

Transient phase-locking and dynamic correlations: Are they the same thing?

Karl J. Friston, K.M. Stephan, R.S.J. Frackowiak
1997 Human Brain Mapping  
This point is demonstrated using the gamma-frequency (36 Hz) component of neuromagnetic signals measured in the prefrontal and partial regions of a subject during self-paced movements.  ...  The first is the characterization of dynamic correlations in multiunit recordings of spike activity using joint-peri-stimulus time histograms (J-PSTHs) [Aertsen and Preissl, 1991: Non Linear Dynamics and  ...  Cathy Price, for help with data acquisition and the presentation of this work.  ... 
doi:10.1002/(sici)1097-0193(1997)5:1<48::aid-hbm5>3.0.co;2-n pmid:20408209 fatcat:y5iluq2smzhwdbz4zivzymjds4
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