Hi all,
I am trying to analyze fMRI data for each individual subject, while
incorporating their behavioral responses. I understand that the correct
way to do it in FSL would be by using the 3-column format and know what
should go in each column. However, it is unclear to me how exactly to
structure the timing of these columns.
In my experiment, subjects see a stimulus on the left or right side of the
monitor. There are two main conditions - imitation and reversal. In the
imitation condition, subjects are asked to press the left button when the
stimulus appears on the left and the right when it appears on the right.
The reversal condition is simply the opposite - see left, press right etc.
Scanning order is 8 imitation trials, 8 reversal trials, 4 rest. This is
repeated 4 times. TR = 3.
My goal at this point is to contrast imitation and reversal EVs. My
understanding is that in the first column I need to put onset time, in the
second column duration, and in the third subject's actual response (e.g.,
1=correct, -1=incorrect, 0=no response). As the onset time for each EV is
supposed to start with 0, it is unclear to me what would be the correct
way to structure the timing of these columns in a way that would enable
contrast of imitation with reversal conditions (since the procedure starts
with imitation and continues with reversal).
Any suggestions and/or examples are appreciated.
Thanks a lot,
Yuri Rassovsky, Ph.D.
Assistant Research Psychologist
Dept. of Psychiatry & Biobehavioral Sciences
UCLA Neuropsychiatric Institute & Hospital
760 Westwood Plaza (C8-747/NPI)
Los Angeles, CA 90024-1759
Phone: (310) 478-3711 ext. 43197
Fax: (310) 268-4056
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