Nonlinear regression in parametric activation studies
Nonlinear regression in parametric activation studies
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DOI：
10.1006/nimg.1996.0029
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发表时间：
1996-08-01
期刊：
影响因子：
5.7
通讯作者：
Friston, KJ
中科院分区：
文献类型：
--
作者：
Buchel, C;Wise, RJS;Friston, KJ
参数化研究设计可以揭示功能成像中研究参数（如单词呈现率）与区域脑血流量（rCBF）之间关系的信息。大脑对研究参数的反应可能是非线性的，因此在参数研究分析中经常使用的（线性）相关系数可能不是一个适当的表征。本文提出了一种非交互方法，利用二阶多项式展开拟合刺激或任务参数的非线性函数对rCBF响应的拟合。该技术是在一般线性模型和统计参数映射的背景下实现的。我们还考虑了基于F场的统计推断在不同群体中这些非线性响应的相似性和差异性的有用性。这种方法是用一个12次运行(H2O)-O-15 PET激活研究来说明的，该研究使用了增加单词呈现率的听觉范式。本文对1例重度失语症患者与正常对照进行了研究。我们展示了这种新技术的能力，在不限制这种关系的性质和这些非线性反应不同的情况下，识别rCBF与增加单词呈现率密切相关的大脑区域。(C) 1996学术出版社，Inc.
Parametric study designs can reveal information about the relationship between a study parameter (e.g., word presentation rate) and regional cerebral blood flow (rCBF) in functional imaging. The brain's responses in relation to study parameters might be nonlinear, therefore the (linear) correlation coefficient as often used in the analysis of parametric studies might not be a proper characterization. We present a noninteractive method, which fits nonlinear functions of stimulus or task parameters to rCBF responses, using second-order polynomial expansions. This technique is implemented in the context of the general linear model and statistical parametric mapping. We also consider the usefulness of statistical inferences, based on F fields, about similarities and differences of these nonlinear responses in different groups. This approach is illustrated with a 12-run (H2O)-O-15 PET activation study using an auditory paradigm of increasing word presentation rates. A patient who had recovered from severe aphasia and a normal control were studied. We demonstrate the ability of this new technique to identify brain regions where rCBF is closely related to increasing word presentation rate in both subjects without constraining the nature of this relationship and where these nonlinear responses differ. (C) 1996 Academic Press, Inc.