Dear list,
After reading this email:
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind05&L=SPM&P=R466366&I=-3
and Good et al. (NeuroImage 14, 2001, p22, 2nd column), our complete
data set of 202 SPGR scans was reoriented (via the Display button) by
one person. About 10-15% of the
scans were in the range specified in the email above. After this the
reoriented data was segmented and smoothed with 8mm.
To see the effect of reorientation we performed a paired t-test pre-
vs postreorientation of the SMWC1, SMWC2 and SMWC3 separately, with
the settings listed below.
The results are in the PDF files attached. There seem to be very
strong differences between the pre- and postreorientation data and we
do not know how to explain them or whether or not we should worry
about such effects.
Any suggestions are greatly appreciated.
Thank you,
Simone Reinders and Andy Simmons.
King's College London
Institute of Psychiatry (IoP)
London, UK.
- independency setting as 'no'
- variance 'unequal'
- grand mean scaling as 'no'
- threshold masking: 'none'
- impliciet mask 'yes'
- expliciet mask '<none>'
- global calculation 'omit'
- global normalisation
- overall grand mean scaling 'no'
- normalisation 'none'
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