Frequently Asked Questions

Why won’t my structural image segment properly?

See What to do when tissue class segmentation fails in SPM.

Why is voxelwise FDR correction not available in SPM8, like it was in SPM5?

In SPM8, by default FDR correction is implemented at the cluster (rather than the voxel) level. Some of the rationale for this change is explained in [Chumbley2009]. To enable voxelwise FDR correction, you need to set defaults.stats.topoFDR to 0 (the default is 1). (For details on how to do this, see Viewing or changing SPM Defaults).

How do I unsubscribe from the SPM or FSL email list?

(Both of these are hosted at JISCmail, so the instructions are the same.)

  1. Go to and click on “subscribers corner”.
  2. Log in if not already (if you don’t know your password, you can choose a new one—this only takes a minute).
  3. From “subscribers corner”, you will see a list of email lists to which you are subscribed. Tick the boxes next to the ones from which you’d like to unsubscribe, and select “unsubscribe” from the dropdown menu.

This method is much more effective than emailing the entire list that you’d like to unsubscribe! ;-)