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Dear Austin,


> One of our subjects has substantial movement artifacts (probably due to a
> sneeze or cough during the MRI) in a couple of volumes.  Is it possible to
> remove these specific volumes from our fMRI analysis?  If this is 
> possible, how
> might I remove them from the analysis?

Of course, best to discard the data set if you can afford this. Otherwise, 
this is what WE do:


Magn Reson Imaging. 2007 Jul;25(6):894-901. Epub 2007 May 8.
Modelling large motion events in fMRI studies of patients with epilepsy. 
Lemieux L, Salek-Haddadi A, Lund TE, Laufs H, Carmichael D.


Basically, every bad volume (incl. neighbours) is nulled by means of 
modelling delta functions as counfounds. As opposed to simply removing bad 
volumes from the time series, this does not mess up your filtering 
("invisble" sin/cos regressors) and you won't get confused with your 
regressors of interest when "renumbering"/"re-timing" your events.

Hope this helps,

Bw

Helmut

P.S: I think you will find more on this in old postings.