Hi - in general if your data has odd unmodelled effects in it then it
will affect the model fitting - usually in an undesirabe way.
Cheers.
On 1 Aug 2007, at 19:12, Vishwadeep Ahluwalia wrote:
> Hi Steve,
> This signal drop is present in the raw time series as well. By the
> way,we
> use the spiral in/out sequence and we discard the first 5 scans
> (10s)(so we
> need to discard 2 more scans)..The cause might be the
> sequence..i'll run
> some tests later. However, I do get some activation even if i
> include the
> first two scans in the GLM but i'd like to know how it would affect
> the PEs
> and/or other results? would it affect the pre-processing or
> registration in
> any way? Thanks!
> -Vish
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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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