Hi all,
I figured I would have some luck tapping expertise on using optseq2 in
this mailing list. There are 8 trials times 8 conditions in an
event-related design. We are using a 1-back task just to keep
participants paying attention. Thus, we are not attempting to match the
number of 1-back-yes and 1-back-no trials. In fact, ideally we would
have exactly 1 1-back-yes trial for each of the 8 conditions. The plan
would be to arrive at a paradigm schedule where, for each of the 8
conditions, there is at least 1 set of consecutive trials for that
condition. In this way, if we use only 7 stimuli, then the consecutive
trials can use the same item, and that would constitute the 1-back-yes
event for that condition as in:
1 a1.bmp
2 b1.bmp
0 NULL
3 c1.bmp
2 b2.bmp <--
0 NULL
2 b2.bmp <--first instance of consecutive events from same condition
assigned same item to create a 1-back-yes event
The problem is that I have not discovered any means within optseq to
enforce the criterion that at two consecutive events are from the same
condition for all 8 conditions. The best I can do is create a large
enough pool of paradigm files, and sort through them in the hopes of
finding several that meet this requirement. Can optseq2 be forced to
meet this requirement, either as a normal command line switch, or else
through some clever condition labeling trickery?
Thanks,
Chris