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Mapping the topological organisation of beta oscillations in motor cortex using MEG

Eleanor L. Barratt, Susan T. Francis, Peter G. Morris, Matthew J. Brookes
2018 NeuroImage  
In this paper we first show, in simulation, how to optimise experimental design and beamformer spatial filtering techniques to increase the spatial specificity of MEG derived functional images.  ...  Our results show that, when using an optimised inverse solution and controlling subject movement (using custom fitted foam padding) the spatial resolution of MEG can be of order 3-5 mm.  ...  For MEG, the paradigm was designed to mimic the simulations and thus optimise spatial resolution.  ... 
doi:10.1016/j.neuroimage.2018.06.041 pmid:29960087 pmcid:PMC6150950 fatcat:jkcujzngnzfmddxbeoq4iwinwy

Investigating spatial specificity and data averaging in MEG

Matthew J. Brookes, Johanna M. Zumer, Claire M. Stevenson, Joanne R. Hale, Gareth R. Barnes, Jiri Vrba, Peter G. Morris
2010 NeuroImage  
We show that if appropriate beamformer optimisation is applied, the moving source can be tracked in the cortex.  ...  This study shows that the spatial specificity of MEG beamformer estimates of electrical activity can be affected significantly by the way in which covariance estimates are calculated.  ...  Acknowledgments The authors would like to thank Stephen Robinson and Sarang Dalal for helpful discussions regarding beamforming, and Jon Peirce for initial help with PsychoPy.  ... 
doi:10.1016/j.neuroimage.2009.07.043 pmid:19635575 pmcid:PMC3224863 fatcat:hnodknqugfhcdkt7xeftazylie

Optimising experimental design for MEG resting state functional connectivity measurement

Lucrezia Liuzzi, Lauren E. Gascoyne, Prejaas K. Tewarie, Eleanor L. Barratt, Elena Boto, Matthew J. Brookes
2017 NeuroImage  
Our results provide important insights on experimental design and will prove valuable for future MEG connectivity studies.  ...  In the present paper, we test how practical aspects of experimental design affect the intra-subject repeatability of MEG findings; specifically we assess the effect of coregistration method and data recording  ...  Here, using simulations and experiments, we probe how test-retest repeatability of functional connectivity in MEG can be optimised by changing practical aspects of experimental design.  ... 
doi:10.1016/j.neuroimage.2016.11.064 pmid:27903441 fatcat:bounhk3dqbgzfpcwdiu4sw4fta

A new approach to neuroimaging with magnetoencephalography

Arjan Hillebrand, Krish D. Singh, Ian E. Holliday, Paul L. Furlong, Gareth R. Barnes
2005 Human Brain Mapping  
We discuss the application of beamforming techniques to the field of magnetoencephalography (MEG).  ...  We review several experiments that have used beamformers, with special emphasis on those in which the results have been compared to those observed in functional magnetic resonance imaging (fMRI) and on  ...  When a boxcar experimental design is used, one can statistically compare the active and passive experimental states for each target voxel in the beamformer images, forming so-called statistical parametric  ... 
doi:10.1002/hbm.20102 pmid:15846771 fatcat:xej6cd5manc6va2tkujqi4s64y

Theoretical advantages of a triaxial optically pumped magnetometer magnetoencephalography system

Matthew J. Brookes, Elena Boto, Molly Rea, Vishal Shah, James Osborne, Niall Holmes, Ryan M. Hill, James Leggett, Natalie Rhodes, Richard Bowtell
2021 NeuroImage  
We show that these parameters can be optimised by judicious array design incorporating triaxial MEG measurements.  ...  Here, we conduct a theoretical analysis of the critical parameters that should be optimised for effective source reconstruction.  ...  , coupled with new designs of sensor, might offer array designs which can aid magnetic source imaging.  ... 
doi:10.1016/j.neuroimage.2021.118025 pmid:33838266 fatcat:hzjpuocbhbfh7dkml6if24hcdm

Inferring task-related networks using independent component analysis in magnetoencephalography

H. Luckhoo, J.R. Hale, M.G. Stokes, A.C. Nobre, P.G. Morris, M.J. Brookes, M.W. Woolrich
2012 NeuroImage  
First, we systematically investigate optimisation of time-frequency windows for connectivity measurement.  ...  A novel framework for analysing task-positive data in magnetoencephalography (MEG) is presented that can identify task-related networks.  ...  Acknowledgments We would like to acknowledge the following institutions for their support: the RCUK Digital Economy programme for provision of funding for Henry Luckhoo through the Centre for Doctoral  ... 
doi:10.1016/j.neuroimage.2012.04.046 pmid:22569064 pmcid:PMC3387383 fatcat:wgic32cxanhpnoz2fb7jzwuosm

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  
Optimising experimental design for MEG beamformer imaging NeuroImage 39, 1788-1802 (2008). Van Veen, B. D., Van Drongelen, W., Yuchtman, M. & Suzuki, A.  ...  However, current MEG systems exclude many subject cohorts and experimental paradigms. Our system represents a step change for functional imaging.  ... 
doi:10.1038/nature26147 pmid:29562238 fatcat:hbrn4xargvcztapszehroekhfa

Using OPMs to measure neural activity in standing, mobile participants [article]

Robert A Seymour, Nicholas Alexander, Stephanie J Mellor, George C O'Neill, Tim M Tierney, Gareth R Barnes, Eleanor A Maguire
2021 bioRxiv   pre-print
This in turn underscores the exciting potential of OP-MEG for recording neural activity during naturalistic paradigms that involve movement (e.g. navigation), and for scanning populations who are difficult  ...  However, upon utilisation of a beamformer, the M100 event-related field localised to primary auditory regions.  ...  for help with scanner-cast design and construction.  ... 
doi:10.1101/2021.05.26.445793 fatcat:lelgxoq7yrgwjfiebk66psaliy

Neural responses to rigidly moving faces displaying shifts in social attention investigated with fMRI and MEG

Laura C. Lee, Timothy J. Andrews, Sam J. Johnson, Will Woods, Andre Gouws, Gary G.R. Green, Andrew W. Young
2010 Neuropsychologia  
Furthermore, the MEG beamforming analyses found an STS response in an upper frequency band (30-80 Hz) which peaked in the right anterior region.  ...  Both functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) were used to investigate neural responses elicited when participants viewed video clips in which actors made a rigid shift  ...  technique, rather than to the cognitive processes engaged by the slightly differing experimental designs (block vs event-related used for fMRI and MEG.  ... 
doi:10.1016/j.neuropsychologia.2009.10.005 pmid:19833143 fatcat:ui4idt72tffq7ca7u2umm42vay

Analysis of simultaneous MEG and intracranial LFP recordings during Deep Brain Stimulation: a protocol and experimental validation

Ashwini Oswal, Ashwani Jha, Spencer Neal, Alphonso Reid, David Bradbury, Peter Aston, Patricia Limousin, Tom Foltynie, Ludvic Zrinzo, Peter Brown, Vladimir Litvak
2016 Journal of Neuroscience Methods  
New method: In this paper, we describe an experimental protocol and analysis pipeline for simultaneously performing DBS and intracranial local field potential (LFP) recordings at a target brain region  ...  Results: Using the phantom recordings we demonstrate that with MEG beamforming it is possible to recover oscillatory activity synchronised to a reference channel, despite the presence of high amplitude  ...  The UK MEG community is supported by Medical Research Council grant MR/K005464/1. The Wellcome Trust Centre for Neuroimaging is supported by core funding from the Wellcome Trust 091593/Z/10/Z.  ... 
doi:10.1016/j.jneumeth.2015.11.029 pmid:26698227 pmcid:PMC4758829 fatcat:wj2t76ra2zf4zieuxqslybsmc4

Dynamic state allocation for MEG source reconstruction

Mark W. Woolrich, Adam Baker, Henry Luckhoo, Hamid Mohseni, Gareth Barnes, Matthew Brookes, Iead Rezek
2013 NeuroImage  
This is used to compute time-varying data covariance matrices for use in beamforming, resulting in a source reconstruction approach that can tune its spatial filtering properties to those required at different  ...  Proof of principle is demonstrated with simulated data, and we demonstrate improvements when the method is applied to MEG.  ...  The location of the brain anatomy with respect to the sensors was taken from a real experimental recording as described for the real MEG resting state data (described later) with a sampling rate of 150  ... 
doi:10.1016/j.neuroimage.2013.03.036 pmid:23545283 pmcid:PMC3898887 fatcat:va4rmszpwzhoxemlc4mv3tfieu

Mouth magnetoencephalography: A unique perspective on the human hippocampus

Tim M. Tierney, Andrew Levy, Daniel N. Barry, Sofie S. Meyer, Yoshihito Shigihara, Matt Everatt, Stephanie Mellor, Jose David Lopez, Sven Bestmann, Niall Holmes, Gillian Roberts, Ryan M Hill (+7 others)
2020 NeuroImage  
We conclude that augmenting a scalp-based MEG array with sensors in the mouth shows unique promise for both basic scientists and clinicians interested in interrogating the hippocampus.  ...  Traditional magnetoencephalographic (MEG) brain imaging scanners consist of a rigid sensor array surrounding the head; this means that they are maximally sensitive to superficial brain structures.  ...  Finally, we used the temporal lobe array to construct a beamformer image and tested for regions of the brain which were coherent with the mouth channel.  ... 
doi:10.1016/j.neuroimage.2020.117443 pmid:33059052 pmcid:PMC8214102 fatcat:qf2bvvdxvrcwha5ipvwi6fjlxm

Mouth magnetoencephalography: A unique perspective on the human hippocampus [article]

Tim M Tierney, Andrew Levy, Daniel N Barry, Sofie S Meyer, Yoshihti Shigihara, Matt Everatt, Stephanie Mellor, Jose David Lopez, Sven Bestmann, Niall Holmes, Gillian Roberts, Ryan M Hill (+7 others)
2020 biorxiv/medrxiv   pre-print
We conclude that augmenting a scalpbased MEG array with sensors in the mouth shows unique promise for both basic scientists and clinicians interested in interrogating the hippocampus.  ...  Traditional magnetoencephalographic (MEG) brain imaging scanners consist of a rigid sensor array surrounding the head; this means that they are maximally sensitive to superficial brain structures.  ...  Finally, we used the temporal lobe array to construct a beamformer image and tested for regions of the brain which were coherent with the mouth channel.  ... 
doi:10.1101/2020.03.19.998641 fatcat:utdewuhwnjaxfcdssysb5iqjoy

Using OPMs to measure neural activity in standing, mobile participants

Robert A. Seymour, Nicholas Alexander, Stephanie Mellor, George C. O'Neill, Tim M. Tierney, Gareth R. Barnes, Eleanor A. Maguire
2021 NeuroImage  
This in turn underscores the exciting potential of OP-MEG for recording neural activity during naturalistic paradigms that involve movement (e.g. navigation), and for scanning populations who are difficult  ...  However, upon utilisation of a beamformer, the M100 event-related field localised to primary auditory regions.  ...  for help with scanner-cast design and construction.  ... 
doi:10.1016/j.neuroimage.2021.118604 pmid:34555493 pmcid:PMC8591613 fatcat:6z4mhfahozcvzlkrq56sngqgyu

Towards an Objective Evaluation of EEG/MEG Source Estimation Methods: The Linear Tool Kit [article]

Olaf Hauk, Matti Stenroos, Matthias Treder
2019 bioRxiv   pre-print
We hope that our approach will help EEG/MEG researchers in the interpretation of source estimation results, the design of new experiments, and the development of new MEG systems.  ...  Here, we describe a framework for resolution analysis of EEG/MEG source estimation, focusing on linear methods.  ...  Variations exist that optimise beamformers for pairs of dipolar sources (Brookes et al., 2007) and for time-and frequency-dependent beamforming (Dalal et al., 2008; Woolrich et al., 2013) .  ... 
doi:10.1101/672956 fatcat:6mosf3grfncmtiqhe37giosm3u
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