 |
 |
On Tue, 6 Sep 2005, Laura Mancini wrote: > I've got a block design with 8 cycles of 24s rest and 24s task (picture > naming), when I select fMRI model/specify design, I choose to specify the > design in scans, in my case the number of condition is 1, I specify the > vector of onset, and then SPM asks me to specify the "duration [s] (event = > 0)", what is exactly this duration? How do I decide how long should it be? > Because varying it, the activation map changes a lot. This is the duration of your task block (in scans, if you specified your design in scans), i.e. the number of scans in your 24s stimulation period. This does not need to be an integer number. In addition, remember that your experiment starts at scan# zero and not at scan# one... -- Volkmar Glauche - Department of Neurology [log in to unmask] Universitaetsklinikum Freiburg Phone 49(0)761-270-5331 Breisacher Str. 64 Fax 49(0)761-270-5416 79106 Freiburg