An example of a parametric contrast is given in Statistical Parametric
Mapping, Color Plate 15.
Chapter 9 should help you with contrasts (the one you give is an
F-contrast).
For parametric modulations, see pg. 62 in the manual; it links to 2
papers. There is also an example in Chapter 29, w/ the example dataset.
Otherwise, you should scour the email archives. It also helps to read
the source code and the manual. And try to read as many methods papers
as you can. There are tons of presentations online, going through an SPM
analysis, and fMRI analysis in general.
James wrote:
> Dear SPMers,
>
> As a beginner, I have read SPM manual, Human Brain Function, Statistical
> Parametric Mapping: The Analysis of Functional Brain Images, and watched FIL
> SPM course CD...
>
> But from all of them, I couldn't find systematical answers to even very simple
> questions about SPM: e.g., how to define contrast for parametric
> modulations? what does a contrast [1 0 0; 0 1 0] mean? If you define a
> parametric modulation P under a condition C, then in your design metric you
> will have both C and C*P as regressors - aren't they correlated?...
>
> So, is there any book / website which can teach one comprehensively master
> SPM? what is the most effective way to master SPM?
>
> Looking forward to your help.
> Thank you very much!
> James
>
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