-tshift_opts_ts -tpattern alt+z

             S L I C E   N U M B E R
   tpattern    0   1   2   3   4   Comment
   --------- --- --- --- --- ---   -------------------------------
   altplus     0 600 200 800 400   Alternating in the +z direction
   alt+z2    400   0 600 200 800   Alternating, but starting at #1
   altminus  400 800 200 600   0   Alternating in the -z direction
   alt-z2    800 200 600   0 400   Alternating, starting at #nz-2 
   seqplus     0 200 400 600 800   Sequential  in the +z direction
   seqminus  800 600 400 200   0   Sequential  in the -z direction

  If @filename is used for tpattern, then nz ASCII-formatted numbers
  are read from the file.  These indicate the time offsets for each
  slice. For example, if 'filename' contains
     0 600 200 800 400
  then this is equivalent to 'altplus' in the above example.
  (nz = number of slices in the input dataset)

N.B.: if you are using -tpattern, make sure that the units supplied
      match the units of TR in the dataset header, or provide a
      new TR using the -TR option.