Hello, Actually, although the rotation parameters are plotted in degrees, I think the units for the rp_*.txt values are radians. Jonathan On Mon, Apr 12, 2010 at 3:05 PM, SALEM BOUSSIDA <[log in to unmask]> wrote: > The units of head motion are in millimeters for the first three > columns(x,yand z translations) and in degrees for the last three ones > (pitch, roll and yaw). > for details see "spm_realign" file.