Toward noninvasive 3-D imaging of the time course of cortical activity: Investigation of the depth of the event-related optical signal
Toward noninvasive 3-D imaging of the time course of cortical activity: Investigation of the depth of the event-related optical signal
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DOI：
10.1006/nimg.2000.0565
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发表时间：
2000-05-01
期刊：
影响因子：
5.7
通讯作者：
Fabiani, M
中科院分区：
文献类型：
--
作者：
Gratton, G;Sarno, A;Fabiani, M
事件相关光信号(EROS)是最近被提出的一种无创研究局部皮质区域活动时间过程的方法(G.Gratton和M.Fabiani，1998，心理学Bull)。启示录5：-563)。以前的数据表明，EROS具有很好的时间分辨率，可以提供详细的表面活跃图。在目前的研究中，我们调查了活动区域的深度是否也可以估计出来。在一项研究中，9名受试者的视觉刺激的偏心率是不同的，并使用多个源-探测器距离记录枕骨内侧区域的性欲。其中7名受试者也使用相同的方案进行了功能磁共振成像(FMRI)研究。FMRI数据显示，从头部表面到激活的皮质区域的深度随着视觉刺激的偏心而系统性地增加。EROS记录显示对刺激的反应潜伏期为60-80ms。这种响应随偏心率而有系统地变化，因此，刺激的偏心率越大，观察到性爱效应的源-探测器距离(从而深度)就越长。产生性爱效应的大脑区域的深度是使用一种简单的算法估计的，该算法来自于对均匀介质的体模研究。EROS得到的每个偏心状态的平均深度估计与fMRI得到的一致，误差小于1 mm。这些数据表明，可以使用多个源-探测器距离来估计引起性爱效应的大脑皮层区域的深度。(C)2000年学术出版社。
The event-related optical signal (EROS) has been recently proposed as a method for studying noninvasively the time course of activity in localized cortical areas (G. Gratton and M. Fabiani, 1998, Psychonomic Bull. Rev. 5: 535-563). Previous data have shown that EROS has very good temporal resolution and can provide detailed surface activity maps. In the present study we investigated whether the depth of the active area can also he estimated. Nine subjects were run in a study in which the eccentricity of the visual stimuli was varied, and EROS was recorded from medial occipital areas using multiple source-detector distances. Seven of the same subjects were also run through a functional magnetic resonance imaging (fMRI) study using the same protocol. The fMRI data indicated that the depth from the head surface to the cortical area activated increased systematically with the eccentricity of the visual stimuli. The EROS recording indicated a response with a latency of 60-80 ms from stimulation. This response varied systematically with eccentricity, so that the greater the eccentricity of the stimuli, the longer the source-detector distance (and thus the depth) at which the EROS effect was observed. The depth of the brain area generating the EROS effect was estimated using a simple algorithm derived from phantom studies on homogeneous media. The average depth estimates for each eccentricity condition obtained with EROS corresponded with those obtained with fMRI, with discrepancies of less than 1 mm. These data demonstrate that multiple source-detector distances can be used to estimate the depth of the cortical areas responsible for the EROS effects. (C) 2000 Academic Press.