The total time is the time from when you start the scanner until the scanner turns off. The duration of the stimulus should be the just that of the stimulus. If you want to have a minimum amount of fixation between events, then use --tnullmin.
doug On 05/05/2014 12:53 PM, Conchy PF wrote: > > Hi everybody, > > I have a question about optseq2. > > In order to calculate ntp, I need to know the total time that my run > lasts. Thus, I do not know whether I have to include in the total > trial time the fixation cross time (500 ms) + event (1000 ms) + > variable ISI average (1 s, ranging from 500 to 4000 ms), or not to > include the variable ISI, increasing the total run time by 50% at the end. > > On the other hand, I have the same dilema about the event command (ev) > and the duration of the stimulus that I should set. Also, if I use the > fixation cross plus event duration, they would add together 1.5 ms, > while the tr is 2. According to the program's instructions, the > stimulus duration must be a multiple of tr. Then, I guess that I > should use to calculate the whole thing the fixation cross (500 ms) + > the event (1000) + the variable ISI average (1 s). Am I right? > > Thank you very much and kind regards, > > C > > > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer -- Douglas N. Greve, Ph.D. MGH-NMR Center gr...@nmr.mgh.harvard.edu Phone Number: 617-724-2358 Fax: 617-726-7422 Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting FileDrop: https://gate.nmr.mgh.harvard.edu/filedrop2 www.nmr.mgh.harvard.edu/facility/filedrop/index.html Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/greve/ _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer 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.
