Zarahn E, Aguirre G, D'Esposito M
Department of Neurology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA.
Neuroimage. 1997 Aug;6(2):122-38. doi: 10.1006/nimg.1997.0279.
An experimental design for functional MRI (fMRI) is presented whose conceptual units of analysis are behavioral trials, in contrast to blocks of trials. This type of design is referred to as a trial-based (TB) fMRI design. It is explained how TB designs can afford the ability to: (1) randomize the presentation of behavioral trials and (2) utilize intertrial variance in uncontrolled behavioral measures to examine their functional correlates. A particular type of TB design that involves modeling trial-evoked fMRI responses with one or more shifted impulse response functions is described. This design is capable of discriminating functional changes occurring during temporally separated behavioral subcomponents within trials. An example of such a design is implemented and its statistical specificity, functional sensitivity, and functional specificity are tested.
本文提出了一种功能磁共振成像（fMRI）的实验设计，其分析的概念单元是行为试验，而非试验块。这种设计类型被称为基于试验（TB）的fMRI设计。文中解释了TB设计如何能够：（1）随机呈现行为试验，以及（2）利用未控制行为测量中的试验间方差来检查其功能相关性。描述了一种特殊类型的TB设计，该设计涉及用一个或多个移位脉冲响应函数对试验诱发的fMRI反应进行建模。这种设计能够区分试验中时间上分离的行为子成分期间发生的功能变化。实现了这种设计的一个示例，并测试了其统计特异性、功能敏感性和功能特异性。
