Dear SPMers,
I meet a problem in 1st level analysis for block-designed fMRI data. I found in some subjects that the SPM results are stripe like (an example please see attached) whereas in other subjects they are OK. In my study, elderly subjects are asked to passively viewing some movie clips (each lasting 15s) containing different emotions, and the control condition is to watch fixation (appears between two movie clips, lasting 15s). Each subject got a two session scan, and the length of each session is about 4 min. My TR = 3s and TE = 30ms. It seems that the stripe like results are not related with head movement because the most severe stripe like results are not found in the subject with most severe head movement. Have you ever met such results before? Any advice and suggestion is welcome.
Sun Delin
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