help > RE: preprocessing physiological data
Jun 9, 2013  05:06 AM | Alfonso Nieto-Castanon - Boston University
RE: preprocessing physiological data
Hi Vincent,

The CompCor algorithm (Behzadi et al. 2007) implemented in the CONN toolbox does not require obtaining any subject physiological data, as it derives potential physiological as well as movement effects on the BOLD timeseries by evaluating the signal within 'noise' ROIs (white matter and CSF areas). That said, if you have physiological data, I believe one useful way to incorporate that into CONN would be to use the RETROICOR method (Glover et al. 2000), which derives a set of regressors optimized to capture most of the variance induced by physiological effects on the BOLD timeseries, and add those regressors as additional confound effects into the CONN toolbox (I have not used this so I do not know the details but I believe you should be able to use the PhLEM toolbox to get the RETROICOR-based regressors as well).

Hope this helps
Alfonso
 
Originally posted by Vincent Beliveau:
Good day,

For another study, I was previously given physiological data formatted to be compatible with CONN (one sample per frame of MRI data). I am processing a new study now and I only have access to the raw physiological data, sampled at a much higher rate than the MRI data. I was thinking of downsampling the data using PhLEM toolbox, however I was wondering if there was a better way to preprocess the physiological data to obtain optimal results with the CompCorr algorithm used by CONN.
Any suggestions?

Kind regards,
Vincent.

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TitleAuthorDate
Vincent Beliveau Jun 7, 2013
RE: preprocessing physiological data
Alfonso Nieto-Castanon Jun 9, 2013
Amr Farahat Aug 10, 2018