Dear all,
i got three silly questions :) :
1) I'm doing a mini block design in an (actual) event-related paradigm,
because, as we have trials of
about 3 seconds consisting each of a serial of
cue-pause-stimulus-response window, it's not possible
to model cue and stimulus separately and simultaneously (as they are
correlated and the pause between
them is always not more than 1200 ms). Am i right?
2) If i am, would you suggest to skip slice timing (i know it's not
necessary for blocks of bigger
size, but these are real short ...and I am interested in the typical
shape of the BOLD response in every condition,
what would require slice time correction in an event-related experiment)?
3) The pause has got a variable extent of 900 to 1200 ms in order to
yield a jitter and decrease expectancy.
In spm2 i can only model constant block lengths (to my humble
knowledge). So we thought about dropping time at the end
of the longer blocks by modeling only blocks of a length of the shortest
one. Could this be a problem for the statistics?
Best regards,
Markus Staudinger
AG Kognitive Neurologie
Institut für Medizin
Forschungszentrum Jülich
52425 Jülich
E-Mail: [log in to unmask]
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