nipreps / fmripost-phase

An attempt at an fMRIPost workflow for handling phase data
Apache License 2.0
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Calculate HighCor confounds #7

Open tsalo opened 1 month ago

tsalo commented 1 month ago

What would you like to see added in fMRIPost-Phase?

I believe it is essentially tCompCor with voxels identified by phase variation. See Curtis and Menon (2014).

From Caballero-Gaudes and Reynolds (2017):

In the HighCor approach (Curtis and Menon, 2014), magnitude nuisance regressors are defined as the principal components of the voxels with the largest phase-amplitude correlations (e.g. the top 2% of voxels). The rationale of HighCor is that selecting voxels based on the temporal standard deviation (tSTD-CompCor) (Behzadi et al., 2007) might not be sufficient to capture subtle physiological confounds with low peak-to-peak fluctuations, such as artefacts related to the helium pump. Since these artefacts are more clearly seen in the phase time series than in the magnitude time series (Hagberg et al., 2012), they can be compensated if a phase-regression approach is used for voxel selection in CompCor. Despite the potential advantage, both HighCor and CompCor achieved a similar increase in temporal SNR, although both methods seem to be complementary and explain different noise components present in the data because their combination helps to further increase the temporal SNR of the signal (Curtis and Menon, 2014).

Do you have any interest in helping implement the feature?

Yes

Additional information / screenshots

No response