> thank you for your help. Another problem is, that these broken scans not
> only
> confuse the statistical evaluation, but also the realignment procedure.
> We detect spikes in e.g. head translation of up to 5 mm at the time of
> the artefact. But as realignment computes the parameters independently for
> every single scan this may have no impact on the rest of the time series.
> (?)
Rigid-body transformation parameters are indeed estimated independently for
each scan so (unless the spikes are present in the first image), they should
not have any influence on the rest of the time series (unless you do the
adjustment, which I don't generally recommend).
Best regards,
-John
Dr John Ashburner.
Functional Imaging Lab., 12 Queen Square, London WC1N 3BG, UK.
tel: +44 (0)20 78337491 or +44 (0)20 78373611 x4381
fax: +44 (0)20 78131420 http://www.fil.ion.ucl.ac.uk/~john
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