Hi Sun,
Do you use the slice timing correction? I have seen this problem when wrong
parameters was used in the slice timing correction. If you use the slice
timing correction, check the parameter whether "slice order" corresponds
with the actual order of image aquisition, like ascending, discending or
interleave.
Hope this helps,
Hisakazu T Yanaka
----- Original Message -----
From: "Sun Delin" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, May 13, 2010 12:07 PM
Subject: [SPM] Stripe like results in 1st level analysis
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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