Title
Optimized beamforming for simultaneous MEG and intracranial local field potential recordings in deep brain stimulation patients.
Abstract
Insight into how brain structures interact is critical for understanding the principles of functional brain architectures and may lead to better diagnosis and therapy for neuropsychiatric disorders. We recorded, simultaneously, magnetoencephalographic (MEG) signals and subcortical local field potentials (LFP) in a Parkinson's disease (PD) patient with bilateral deep brain stimulation (DBS) electrodes in the subthalamic nucleus (STN). These recordings offer a unique opportunity to characterize interactions between the subcortical structures and the neocortex. However, high-amplitude artefacts appeared in the MEG. These artefacts originated from the percutaneous extension wire, rather than from the actual DBS electrode and were locked to the heart beat. In this work, we show that MEG beamforming is capable of suppressing these artefacts and quantify the optimal regularization required. We demonstrate how beamforming makes it possible to localize cortical regions whose activity is coherent with the STN-LFP, extract artefact-free virtual electrode time-series from regions of interest and localize cortical areas exhibiting specific task-related power changes. This furnishes results that are consistent with previously reported results using artefact-free MEG data. Our findings demonstrate that physiologically meaningful information can be extracted from heavily contaminated MEG signals and pave the way for further analysis of combined MEG-LFP recordings in DBS patients.
Year
DOI
Venue
2010
10.1016/j.neuroimage.2009.12.115
NeuroImage
Keywords
Field
DocType
region of interest,time series,local field potential
Developmental psychology,Beamforming,Deep brain stimulation,Neocortex,Neuroscience,Psychology,Motor cortex,Local field potential,Cerebral cortex,Subthalamic nucleus,Magnetoencephalography
Journal
Volume
Issue
ISSN
50
4
1053-8119
Citations 
PageRank 
References 
21
1.37
9
Authors
11
Name
Order
Citations
PageRank
Vladimir Litvak138426.00
Alexandre Eusebio2211.71
Ashwani Jha3232.18
Robert Oostenveld4130080.66
Gareth R Barnes584064.63
William D. Penny646659.78
Ludvic Zrinzo7343.51
Marwan Hariz8695.74
Patricia Limousin9363.98
Karl J Friston104455347.58
Peter Brown11275.71