Hello all,
my student and I are looking at the 7T motion files. We used the following R function (see below) to calculate the FD for the scans. We found (what seems to be) very high FD exceeding thresholds particularly given that these are adults watching a movie. Out of 92 subjects, 49 had 25% or more of their volumes with a FD >= 0.2.
library(fMRIscrub)
X ← read.table(“~/Desktop/TESTMovement_Regressors.txt”, header = FALSE)
motion_params ← as.matrix(X[, 1:6])
fd_result ← FD(motion_params, cutoff = 0.2, rot_units = “deg”, trans_units = “mm”)
As an example:
For sub 126931 they had 85% of their volumes with an FD of 0.2mm or greater.
Has anyone else run into this issue? Or am totally calculating FD incorrectly?
Thank you and all the best,
Grace