Under certain circumstances (e.g. data that is arbitrarily scaled and comes from several sources has to be compared), one way to normalize (re-scale) the data is to apply z-transformation (setting the mean of values in the desired dimension to 0 and the standard deviation to 1).
ztrans - perform z-transformation on time course FORMAT: [ztc, zf, zsh] = ztrans(tc [, dim [, tp]]) Input fields: tc time course data dim temporal dimension (default: first non-singleton) tp time points (indices of dim to use for normalization) Output fields: ztc z-transformed time course zf z-transformation factor zsh z-transformation shift See also psctrans
ztc = ztrans(tc);
vtc.VTCData = ztrans(vtc.VTCData, 1);
nii.VoxelData = ztrans(nii.VoxelData, 4);
[ztc, zfactor, zshift] = ztrans(tc);