On 8 Jul 2016, at 09:31, Zerbi Valerio <[log in to unmask]> wrote:

Dear FSL experts,

I have a quick question that relates to the correct use of Dual_Regression inputs.

According to the wiki, one needs to use the group-melodic_IC.nii.gz file as input-mask for the dual_regression . I was wondering if the script itself applies a threshold on these ICs (e.g. 75th percentile) before measuring the mean time series, or it uses a weighted mean on the ICs scores.

No - no thresholding.

My question is then, is it valid to use a binary group-ICA masks (obtained from a separate control-group of subjects) to perform stage1 of dual regression? Or shall I use the original whole brain ICs not thresholded?

In general best to use the original maps as the dualreg regressors.

Cheers.

Best,

Valerio

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Valerio Zerbi | PostDoc fellow

Department of Health Sciences and Technology (D-HEST) | ETH Zürich

Y36 M12 | Winterthurerstrasse 190 | 8057 Zürich | +41 44 63 56101

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