Test-retest reliability estimation of functional MRI data
Test-retest reliability estimation of functional MRI data
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DOI：
10.1002/mrm.10191
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发表时间：
2002-07-01
影响因子：
3.3
通讯作者：
Gullapalli, RP
中科院分区：
文献类型：
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作者：
Maitra, R;Roys, SR;Gullapalli, RP
功能性磁共振成像（fMRI）数据通常用于构建人类大脑的激活图。重要的是要量化这些地图的可靠性。我们已经开发了统计模型，以提供精确的估计可靠性，从几个运行相同的范例随着时间的推移。具体而言，我们的方法扩展了Genovese等人（Magn Reson Med 1997;38：497-507）开发的最大似然（ML）的前提，将空间背景纳入估计过程。实验表明，我们的方法提供了更保守的估计，真阳性相比，Genovese等人获得的可靠性估计可用于获得体素特定的可靠性措施，以及在未来的实验中激活的区域。我们得出的统计方法来确定区域和上下文特定的激活的最佳阈值。还提供了关于重复扫描次数的经验指南，以获得准确的可靠性估计。我们报告的结果，涉及一个单一的主题上进行了几次，在为期2个月的运动范式的实验。(C)2002 Wiley-Liss，Inc.
Functional magnetic resonance imaging (fMRI) data are commonly used to construct activation maps for the human brain. It is important to quantify the reliability of such maps. We have developed statistical models to provide precise estimates for reliability from several runs of the same paradigm over time. Specifically, our method extends the premise of maximum likelihood (ML) developed by Genovese et al. (Magn Reson Med 1997;38:497-507) by incorporating spatial context into the estimation process. Experiments indicate that our methodology provides more conservative estimates of true positives compared to those obtained by Genovese et al. The reliability estimates can be used to obtain voxel-specific reliability measures for activated as well as inactivated regions in future experiments. We derive statistical methodology to determine optimal thresholds for region- and context-specific activations. Empirical guidelines are also provided on the number of repeat scans to acquire in order to arrive at accurate reliability estimates. We report the results from experiments involving a motor paradigm performed on a single subject several times over a period of 2 months. (C) 2002 Wiley-Liss, Inc.