Requested metric: respiratory variance

[tsalo]

Respiratory variance (RV) is, like RVT, used to measure variability of the respiratory trace. This regressor, especially when convolved with a respiratory response function (RRF), can be used to denoise fMRI data.

Per Power et al. (2018) (appendix):

Second, the RV (respiratory variance) measure was created from the standard deviation of the respiratory trace within a 6-second window (following (7)), and this trace was lagged back 3 seconds and forward 3 seconds to create 3 regressors, and each of these regressors was convolved with the RRF defined above for a total of 6 respiratory regressors.

[CesarCaballeroGaudes]

The implementation of this approach is within our plans for phys2denoise. Keep tuned.