Hi there,
I am trying to calculate the percent signal change from a contrast (A > B), with both stimulus durations (A and B) being 10s. Note A is the task, B is the control task. I followed Jeanette's tutorial using command line (not featquery) tools and calculated the height in matlab for 10s. Is this OK to use as scaling factor? I am a bit uncertain as I understand the duration and thus the scaling factor comes from the EVs and not from the contrast...
Another complication is that A is presented once with 7, once with 10s (B is always 10s), thus theoretically I'd have 2 different scaling factors. What would be the correct way of dealing with this?
Thanks very much for any comments.
Yours desperately,
Torsten
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