This is unsolicited. but with any sort of motion you have to be careful of artifact. This paper may be of relevance:
Hum Brain Mapp. 2005 Mar;24(3):173-83
Comparison of continuous overt speech fMRI using BOLD and arterial spin labeling.
Kemeny S, Ye FQ, Birn R, Braun AR.
Best of luck,
-Robert Welsh
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Robert C. Welsh, PhD
Research Assistant Professor
Departments of Radiology and Psychiatry
University of Michigan
(734) - 764 - 8541 (fax)
(734) - 647 - 6781 (Ofc)
rcwelsh @ med.umich.edu
>>> Oshrat Sella <[log in to unmask]> 07/16/09 11:51 PM >>>
Hello
I`m fairly new in the area of fMRI and while working on my research design I
had a few questions. I`m going to use event related design, with 2 types of
swallowing tasks: water and dry swallows, randomized in order. The tasks are
going to be visually cued, and the time between each swallow is 45 sec. We
will compare the brain activity pre and post swallowing treatment. We are
going to use 3T scanner.
My questions are regarding the analyses of the fMRI data. According to the
literature some researchers used an external marker for the swallowing event
(surface EMG electrodes or pressure belt on the thyroid cartilage) and some
did not use any marker, and I guess that they used the timing of the cues as
the marker.I didn`t find any works that compared the use of external markers
and timing of the cues, so I`m struggling with this issue.
Does anyone have experience with this kind of work? If so, what is your
opinion about using or not using an external marker?
From what I have understood the peak of the BOLD response happens 9-12 sec
after the swallow, unlike other tasks where the peak happens after 6 sec.
What model should I use in interpretation the data? we were thinking about
the FIR model, and since we haven`t used that in our lab yet, any feedback
can help.
What are the Lags I should enter into the model, since there is variation in
the peak timing?
Thanks for any suggestions,
Oshrat Sella
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