-6-
²Examination
of time series fred2_epi+orig
and fred2_epi_vr_+orig shows that head movement up and down happened within
about 1 TR interval
åAssumption
of rigid motion of 3D volumes is not good for this case
åCan do
2D slice-wise registration with command
2dImReg
-input fred2_epi+orig \
-basefile fred1_epi+orig \
-base 4 -prefix fred2_epi_2Dreg²Graphs of a
single voxel time series near the edge of the brain:
åTop =
slice-wise alignment
åMiddle
= volume-wise adjustment
åBottom
= no alignment
²For this
example, 2dImReg appears to produce better results. This is because most of the motion is Ôhead noddingÕ and the acquisition is sagittal
²You should
also use AFNI to scroll through the images (using the Index control) during the period of pronounced movement, on all 3 datasets
fred1_epi registered with 2dImReg
fred1_epi registered with 3dvolreg
fred1_epi unregistered