Dear FSLers,
I have fMRI data from an n-back working memory task with three conditions (3-Back, 1-Back, 0-Back). Within the 6:15 scan, there are 6 task epochs (2 each per condition) each lasting 30 seconds with 30 seconds of fixation in between each epoch. The order of the conditions is mirrored (i.e., 3-Back 1-Back 0-Back 0-Back 1-Back 3-Back), supposedly to counter artifactual drifts.
My question is what to choose for a high-pass temporal filter.
Do I select
30 seconds (duration of a single epoch),
60 seconds (1 epoch + 1 fixation),
180 seconds (3 epochs, one of each condition, + 3 fixations),
360 seconds (the full cycle minus the initial and final fixations),
or none (because the mirrored design precludes the need to run HPTF)?
Thanks.
Cheers,
Pete Fried
Department of Anatomy & Neurobiology
Boston University School of Medicine
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