Dear all, Is it possible, with spm command line functions, to read and write 4D NifTI files? After V=spm_vol('fmri_TR2.nii'); with fmri_TR2.nii a 4D NifTI data set, I get an array V of records about the individual volumes in the 4D data set. The fastest way that I know to read data is spm_read_vols, but due to the NifTI record of my file being split into N separate records (???), spm_read_vols only load one volume at a time. For fast reading and writing of 4D data, is there a way to not do this splitting of NifTI records, and load/save the data as a 4D array? Many thanks Alle Meije