I have three files: one file containing the relative position of the probes, whose file type is ".nirs"; one file containing the spatial coordinates of the probes, whose file type is ".csv"; one file containing coordinates of reference points (Lz, AR, AL, Cz, etc). But I don't have MRI data and I hope to use the template data. How can I import the file of probe coordinates into brainstorm and then perform source analysis?