Department of Computational Intelligence and Systems Science, Tokyo Institute of Technology, G3-50, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
J Neurosci Methods. 2009 Nov 15;184(2):213-23. doi: 10.1016/j.jneumeth.2009.08.003. Epub 2009 Aug 12.
Continuous recording of Visual Evoked Potentials (VEPs) and functional Magnetic Resonance Imaging (fMRI) exploits the VEPs high temporal resolution and the fMRI high spatial resolution. In this work, we present a new method of continuous VEPs/fMRI recording to study visual function in seven normal subjects. Our real-time artifact filtering is characterized by a procedure based on an analytical study of echo-planar imaging (EPI) sequence parameters related electro-encephalogram (EEG)-artifact shapes. The magnetic field artifacts were minimized by using a dedicated amagnetic device and by a subtraction algorithm that takes into account the EPI sequence parameters. No significant decrease in signal-to-noise ratio was observed in case of EEG recording simultaneously with MR acquisition; similarly, transient and steady-state VEPs parameters were comparable during fMRI acquisition and in the off-phase of fMRI recording. We also applied this method to one patient with optic neuritis, and, compared with controls, found different results. We suggest that our technique can be reliably used to investigate the function of human visual cortex and properly correlate the electrophysiological and functional neuroimaging related changes.
连续记录视觉诱发电位（VEPs）和功能磁共振成像（fMRI）利用了 VEPs 的高时间分辨率和 fMRI 的高空间分辨率。在这项工作中，我们提出了一种新的连续 VEPs/fMRI 记录方法，以研究 7 名正常受试者的视觉功能。我们的实时伪影滤波方法的特点是基于对与脑电图（EEG）-伪影形状相关的回波平面成像（EPI）序列参数的分析研究的过程。通过使用专用的抗磁设备和考虑 EPI 序列参数的减法算法，最小化了磁场伪影。在同时进行 EEG 记录和 MR 采集的情况下，信号噪声比没有明显下降；同样，在 fMRI 采集期间和 fMRI 记录的非相位期间，瞬态和稳态 VEP 参数是可比的。我们还将该方法应用于 1 名视神经炎患者，并与对照组进行了比较，发现了不同的结果。我们建议我们的技术可以可靠地用于研究人类视觉皮层的功能，并适当相关的电生理和功能神经影像学变化。
