Complete artifact removal for EEG recorded during continuous fMRI using independent component analysis
Complete artifact removal for EEG recorded during continuous fMRI using independent component analysis
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DOI：
10.1016/j.neuroimage.2006.09.037
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发表时间：
2007-01-15
期刊：
影响因子：
5.7
通讯作者：
Del Gratta, C.
中科院分区：
文献类型：
--
作者：
Mantini, D.;Perrucci, M. G.;Del Gratta, C.
脑电和功能磁共振成像的同步记录是一种很有前途的方法，结合电生理和血流动力学信息的大脑动力学。然而，在MRI扫描仪中进行的EEG记录受到成像、心冲击描记术（BCG）和眼部伪影的污染。目前有许多用于消除fMRI环境干扰的处理技术：最流行的是平均伪影减法（AAS），它对成像伪影有很好的去除效果，但由于心动波持续时间和形状的可变性，在去除BCG伪影方面有一定的局限性;此外，目前在EEG/fMRI中没有使用衰减眼伪影的处理方法，并且在信号分析之前简单地拒绝污染的时期。在这项工作中，我们提出了一个全面的方法，同时消除BCG和眼伪影的EEG记录，以及残留的MRI污染AAS的基础上独立成分分析（伊卡）。伊卡方法已被测试的事件相关电位（ERP）从视觉oddball范式：它是非常有效的衰减伪影，以重建清晰的脑信号从EEG中获取的MRI扫描仪。它在去除BCG伪影方面的表现明显优于AAS方法。此外，由于可以完全抑制眼部伪影，因此可以使用大量试验进行分析。磁环境内的ERP与MRI扫描仪获得的ERP的比较证实，没有系统的偏见，在ERP波形产生的伊卡方法。(c)2006年爱思唯尔公司All rights reserved.
The simultaneous recording of EEG and fMRI is a promising method for combining the electrophysiological and hemodynamic information on cerebral dynamics. However, EEG recordings performed in the MRI scanner are contaminated by imaging, ballistocardiographic (BCG) and ocular artifacts. A number of processing techniques for the cancellation of fMRI environment disturbances exist: the most popular is averaged artifact subtraction (AAS), which performs well for the imaging artifact, but has some limitations in removing the BCG artifact, due to the variability in cardiac wave duration and shape; furthermore, no processing method to attenuate ocular artifact is currently used in EEG/fMRI, and contaminated epochs are simply rejected before signal analysis. In this work, we present a comprehensive method based on independent component analysis (ICA) for simultaneously removing BCG and ocular artifacts from the EEG recordings, as well as residual MRI contamination left by AAS. The ICA method has been tested on event-related potentials (ERPs) obtained from a visual oddball paradigm: it is very effective in attenuating artifacts in order to reconstruct clear brain signals from EEG acquired in the MRI scanner. It performs significantly better than the AAS method in removing the BCG artifact. Furthermore, since ocular artifacts can be completely suppressed, a larger number of trials is available for analysis. A comparison of ERPs inside the magnetic environment with those obtained out of the MRI scanner confirms that no systematic bias in the ERP waveform is produced by the ICA method. (c) 2006 Elsevier Inc. All rights reserved.