what are you trying to do exactly? The external regressor is usually used with a continuous measure (eg, skin conductance, it can also be used to seed-based functional connectivity). If you expect the hemodynamic response to be scaled by something (eg, reaction time), then that should be incorporated into the paradigm file in the 4th column.
doug
Katie Bettencourt wrote:
So I just need 1 column with a line for each time point that has the weight I want to give the condition that is occuring at that time point? And what do you mean a contrast will automatically be created for it? I was trying to use this to find an area that increases with load but then plateaus at a point where subject's behavioral performance plateaus (so essentially looking for a mirroring of the behavioral data in the neural data), will there just be a contrast created after I run selxavg3-sess that I can bring up with tksurfer-sess afterwards?
katie
On Tue, Dec 7, 2010 at 11:40 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu mailto:greve@nmr.mgh.harvard.edu> wrote:
It is just a text file with a value for each time point. You can have multiple columns, but if it is a task, then you probably want to keep one to make the interpretation easier. A contrast will automatically be created for it. You can look at the mcprextreg file created by the motion correction to get an idea. doug Katie Bettencourt wrote: I'm trying to set up an analysis using an external regressor (as part of the mkanalysis-sess stream, -taskreg flag) in version 5, but I'm not sure what the taskreg.dat file should look like. The only thing I can find is that it should have a line for each time point. Does anyone have any more guidance than this? Katie ------------------------------------------------------------------------ _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu <mailto:Freesurfer@nmr.mgh.harvard.edu> https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer -- Douglas N. Greve, Ph.D. MGH-NMR Center greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu> Phone Number: 617-724-2358 Fax: 617-726-7422 Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting <http://surfer.nmr.mgh.harvard.edu/fswiki/BugReporting> FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html <http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html> The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.