While clinical examinations generally consider data from each patient separately, neuroscience questions are frequently answered by comparing and combining data from groups of subjects. To achieve this, data from all participating subjects need to be transformed to a common space in a manner that helps compensate for inter-subject differences. This procedure, called morphing by the MNE software, exploits the FreeSurfer spherical coordinate system defined for each hemisphere (Dale et al., 1999; Fischl et al., 1999). The process is illustrated in Figure 5.
