----- Original Message -----
From: Satrajit Ghosh <[log in to unmask]>
Date: Thursday, March 17, 2005 7:50 am
Subject: Re: Any Papers on Presenting fMRI Results?
> Dear Tom,
>
> I think there are two things that need to be shown to statisfy all
> curiosity. A map of %signal change and a logmap of T/Z statistic
> (or a
> map of variability). I am generally in favor of a %signal change map
> but the problem lies in the fact that a small change but consistent
> change would not necessarily be detected in a %signal change map.
> Consistency is what the statistical map shows. That is why Matthew
> showed one with the acitivity map on which the threshold was
> superimposed. We can extend that to show bands for -log(pvalues) on
> it, similar to a terrain map with contour lines on it.
>
> From a functional standpoint we get two different pieces of
> information from the two maps. One tells us "how much" and the other
> tells us "how reliably".
>
> Satra
I agree that the statistical (T or Z) information is important. What I
had in mind was a map where the colour was based upon % signal change
(or another metric that captures amount of signal change, which is
typically what is being compared in image contrasts), and the
thresholding, or contouring, is based upon the T or Z. This provides all
the information in one image.
Tom
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