[caret-users] importing thresholded functional data
zinke at brain.uni-bremen.de
Thu Feb 25 03:16:21 CST 2010
I am sorry for this naive an likely many time answered question, but a
first search did not bring up any clear statement to this issue.
I use caret to view functional data on inflated monkey brains. The data
was analysed with FSL on data oriented according to a coordinate system
based on eye and ear bars, but the caret files use the
anterior,posterior commisure, hence I apply a transformation to my
thresholded functional data (z-values) including a trilinear
interpolation. This of course lead to subthreshold values surrounding
the patches, and reduced, more smooth values within patches. In the step
of mapping the volume data to the surface I again apply
interpolation/averaging of the z-values.
I am wondering now, if this is an accepted procedure and that the
interpolation of statistical maps is in general not seen as a serious
problem. Though the statistics of the maps are reduced and smeared, I
doubt that this introduces a serious misplacement of the activation
foci. However, I don't fell well to present the range of z-values as
'z-values' anymore, because of the interpolation.
I am happy for any pointers regarding such issues.
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