Thank you for the quick reply!

So you would recommend adding the mean image for both dense and parcellated
analyses? Our task runs are 718 volumes each with a TR of 0.72 seconds.

Thanks again,


Andrew Poppe, Ph.D.
Postdoctoral Fellow
Olin Neuropsychiatry Research Center
Institute of Living
Hartford Hospital

On Fri, Jan 27, 2017 at 3:00 PM, Glasser, Matthew <[email protected]>
wrote:

> It is correct that the taskfMRI pipeline requires the data to not be
> demeaned and by default currently the ICA+FIX pipeline produces demeaned
> data with recent versions of FSL because the mean is removed by the
> highpass filter.  It would be sufficient to compute the mean image from the
> uncleaned data and add it to the cleaned data.  If there are any other bugs
> in the taskfMRI Pipeline that interact with ICA+FIX cleaned data, I will
> know about them soon as I am doing similar processing.  How long are your
> task fMRI runs?
>
> Peace,
>
> Matt.
>
> From: <[email protected]> on behalf of Andrew Poppe <
> [email protected]>
> Date: Friday, January 27, 2017 at 12:58 PM
> To: "[email protected]" <[email protected]>
> Subject: [HCP-Users] Problem using FIX clean data in parcellated stats
> pipeline
>
> Howdy HCP folks,
>
> We've recently run into a problem when attempting to use ICA+FIX cleaned
> data in a parcellated stats analysis pipeline. I'll run through what we've
> done, what happened, and what I think is going wrong. Hopefully you can
> provide some insight into if we've done things correctly and if so, what to
> do about it.
>
> We are using the IcaFixProcessingBatch.sh script to apply ICA+FIX to our
> data using the provided HCP_hp2000.RData training data, following the
> application of GenericfMRIVolumeProcessingPipelineBatch.sh and
> GenericfMRISurfaceProcessingPipelineBatch.sh.
>
> This produces a file with a name ending in _Atlas_hp2000_clean.
> dtseries.nii.
>
> Previously, before attempting to use ICA+FIX, we have successfully used
> the TaskfMRIAnalysisBatch.sh script to run a parcellated analysis. In order
> to use ICA+FIX results as our input data, I changed the name of the clean
> data to be ${TASK}_Atlas.dtseries.nii to "trick" the batch script to use
> the cleaned data instead of the original data.
>
> This worked fine when doing a dense analysis, but the analysis failed when
> trying to run a parcellated analysis.
>
> Specifically, when examining the logs of the analysis, the output of
> film_gls included the line: *numTS=0* when using FIX cleaned data when it
> had been *numTS=360* when using the original data.
>
> The film_gls code appears to do some masking of non-brain voxels toward
> the beginning, and this masking process effectively zeroed out all values
> in the FIX cleaned data whereas it allowed all values to remain when using
> original data. Looking at the FAKENIFTI files produced from the original
> data compared with ICA+FIX cleaned data, it seems the ranges are quite
> different.
>
> For the original data (for a representative subject), the mean value of
> the FAKENIFTI was around 11000 (range was ~5000 to ~15000). For the FIX
> cleaned data, the mean was effectively zero (range was -420 to 382).
>
> During the masking procedure in film_gls, a "mask" is produced by
> averaging voxel values across time. Next, that mask is binarized based on a
> user-supplied threshold value. The default threshold value supplied to
> film_gls in the TaskfMRIAnalysis pipeline scripts is 1. In the case of the
> original data, all values in the mask are set to 1 since the range of this
> mean mask volume is 6346.99 to 14440.96. However, for the mean mask created
> from the FIX cleaned data, the range is -2.638159e-06  to 1.118895e-06,
> such that binarizing with a threshold of 1 sets all values to 0.
>
> If I understand this correctly, it seems that this masking procedure
> within film_gls is unnecessary during a parcellated analysis, because we
> already know that there are no "non-brain" values to get rid of. So, I have
> a couple questions about this:
>
> 1) Do the values for the ICA+FIX cleaned data I presented seem
> representative of FIX results in your experience? Meaning, instead of a
> mean around 10000 the data have a zero mean with a greatly reduced range.
> Also, when taking an average across time, is it common to see effectively
> zero values for all parcels?
>
> 2) If the answer to #1 is "yes," would it be okay to circumvent this
> masking process within film_gls? I could imagine altering the pipeline
> script to instead of providing a 1 for the threshold, provide the minimum
> voxel value in the FAKENIFTI instead, insuring that the binarizing
> procedure created a mask of all 1s.
>
> Any help or insight would be greatly appreciated, and please let me know
> if you need more information. The relevant parts of the film_gls.cc code
> are:
>
>       read_volume4D(input_data,globalopts.inputDataName.value());
>       reference=input_data[int(input_data.tsize()/2)-1];
>       copybasicproperties(input_data,reference);
>       mask=meanvol(input_data);
>       variance=variancevol(input_data);
>       input_data-=mask;
>       mask.binarise(globalopts.thresh.value(),mask.max()+1,exclusive);
>       variance.binarise(1e-10,variance.max()+1,exclusive); //variance
> mask needed if thresh is -ve to remove background voxels (0 variance)
>       mask*=variance; //convolved mask ensures that only super-threshold
> non-background voxels pass
>       datam=input_data.matrix(mask,labels);
>
> And the relevant call to film_gls comes in TaskfMRILevel1.v2.0.sh on line
> 235:
>
> film_gls --rn=${FEATDir}/ParcellatedStats --in=${FEATDir}/${
> LevelOnefMRIName}_Atlas"$TemporalFilterString""$
> SmoothingString"${RegString}${ParcellationString}_FAKENIFTI.nii.gz
> --pd="$DesignMatrix" --con=${DesignContrasts} --fcon=${DesignfContrasts}
> --thr=1 --mode=volumetric
>
>
> Cheers,
>
> Andrew Poppe, Ph.D.
> Postdoctoral Fellow
> Olin Neuropsychiatry Research Center
> Institute of Living
> Hartford Hospital
>
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