On 7/15/2019 12:50 PM, Tugce Duran wrote:

External Email - Use Caution Hi Dr. Greve,

I am interested in designing the Face Name Associative Memory Exam (FNAME) fMRI task for our study. There are 80 face-name pairs that we will use and the duration can be between 3.5 and 4.75 secs. I have used the following command: optseq2 --ntp 200 --tr 2 --psdwin 0 32 2 --ev facename 4 80 --nkeep 3 --o trial2 --tnullmin 0 --tnullmax 6 --nsearch 10000 Total scan time appx 6-7 mins.

Q1: For NULL, why do we have only 2 sec and 4 sec jitters? Can we change the variety amount of the jitters? Are more jitters good or bad (instead of just having 2 secs and 4 secs, let’s say we get 0.25, 1, 2, 3 and 4 secs) ? It always makes the NULL durations a integer multiple of the dPSD. You set this to 2 (--psdwin 0 32 2). If you are assuming the shape to the hemodyamic response (eg, the canonical SPM HRF), then it won't matter much if you decrease it to 1 or less). The benefit of jitter in that case depends more on the psychology than the signal processing.

Q2: For the event design I am interested in above, what would be the “best” parameters used? Usually, you set the total time for the NULL to be equal to that of a stimulus type. In this case, you have one stimulus type presented for a total of 320 sec (4*80), so you could set the scan duration to be 320*2=640sec=10min 40sec. That would be optimum for testing your stimulus against baseline, but that is probably not what you are planning to do.

Trial2-001.par: 0.0000 1 4.000 1.0000 facename 4.0000 1 4.000 1.0000 facename 8.0000 1 4.000 1.0000 facename 12.0000 0 2.000 1.0000 NULL 14.0000 1 4.000 1.0000 facename 18.0000 1 4.000 1.0000 facename 22.0000 1 4.000 1.0000 facename 26.0000 1 4.000 1.0000 facename 30.0000 1 4.000 1.0000 facename 34.0000 1 4.000 1.0000 facename 38.0000 1 4.000 1.0000 facename 42.0000 0 4.000 1.0000 NULL 46.0000 1 4.000 1.0000 facename 50.0000 1 4.000 1.0000 facename 54.0000 1 4.000 1.0000 facename 58.0000 1 4.000 1.0000 facename 62.0000 1 4.000 1.0000 facename 66.0000 1 4.000 1.0000 facename 70.0000 1 4.000 1.0000 facename 74.0000 0 2.000 1.0000 NULL 76.0000 1 4.000 1.0000 facename 80.0000 0 2.000 1.0000 NULL 82.0000 1 4.000 1.0000 facename . . . .

372.0000 0 4.000 1.0000 NULL 376.0000 1 4.000 1.0000 facename 380.0000 1 4.000 1.0000 facename 384.0000 1 4.000 1.0000 facename 388.0000 1 4.000 1.0000 facename 392.0000 1 4.000 1.0000 facename 396.0000 1 4.000 1.0000 facename

Thank you in advance!

Tugce

Tugce Duran Graduate Student, Biomedical Sciences MS Program Neuroscience Concentration | Section on Gerontology & Geriatric Medicine, WFSM [2color] Graduate Programs in Biomedical Sciences 525 Vine Street, Suite 150, Winston-Salem, NC 27101 • 317-893-9100 | • tduran@wakehealth.edumailto:tduran@wakehealth.edu | |[Image result for linked in]linkedin.com/in/tugceduran/http://linkedin.com/in/janesmith/ The information contained in this message is privileged and confidential information intended for the sole use of the addressee. If the reader of this message is not the intended recipient, or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this message in error, please notify the person listed above immediately by e-mail, and delete the original message and attachments.