Statistical parametric maps in functional imaging: A general linear approach

TLDR

Statistical parametric maps are spatially extended statistical processes used to test regionally specific effects in neuroimaging, traditionally based on linear models such as ANCOVA, correlation, and t‑tests, and all represent special cases of the general linear model, suggesting a unified framework is feasible. The authors propose a general approach that accommodates most experimental layouts and analyses, integrating fixed‑effect designs with covariates and factor interactions. This approach combines the general linear model with Gaussian field theory to offer a complete and simple framework for imaging data analysis. The framework offers conceptual and mathematical simplicity by using a small set of equations regardless of experiment complexity, and its generality allows great flexibility in experimental design and analysis. © 1995 Wiley‑Liss, Inc.

Abstract

Abstract Statistical parametric maps are spatially extended statistical processes that are used to test hypotheses about regionally specific effects in neuroimaging data. The most established sorts of statistical parametric maps (e.g., Friston et al. [1991]: J Cereb Blood Flow Metab 11:690–699; Worsley et al. [1992]: J Cereb Blood Flow Metab 12:900–918) are based on linear models, for example ANCOVA, correlation coefficients and t tests. In the sense that these examples are all special cases of the general linear model it should be possible to implement them (and many others) within a unified framework. We present here a general approach that accomodates most forms of experimental layout and ensuing analysis (designed experiments with fixed effects for factors, covariates and interaction of factors). This approach brings together two well established bodies of theory (the general linear model and the theory of Gaussian fields) to provide a complete and simple framework for the analysis of imaging data. The importance of this framework is twofold: (i) Conceptual and mathematical simplicity, in that the same small number of operational equations is used irrespective of the complexity of the experiment or nature of the statistical model and (ii) the generality of the framework provides for great latitude in experimental design and analysis. © 1995 Wiley‐Liss, Inc.